NEXO Brain — Your AI Gets a Brain

Local cognitive runtime with a shared brain across Claude Code, Codex, Claude Desktop, and other MCP clients. Persistent memory, durable workflow runs, selectable terminal and automation backends, overnight learning, self-healing background jobs, startup preflight, and doctor diagnostics. 150+ MCP tools. Benchmarked on LoCoMo (F1 0.588, +55% vs GPT-4).

NEXO Brain transforms any MCP-compatible AI agent from a stateless assistant into a cognitive partner that remembers, learns, forgets, adapts, and builds a relationship with you over time.

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Version 7.15.2 is the current packaged-runtime line. Patch release over v7.15.1 - Brain treats normal Codex startup context reads of calibration and project atlas files as healthy bootstrap activity instead of conditioned-file drift.

Previously in 7.15.1: patch release over v7.15.0 - Brain drains larger self-audit clusters, bounds hook history with update-time cleanup, filters normal Codex bootstrap reads, routes email-monitor effort by message complexity, and locks morning briefings by local date and recipient.

Previously in 7.15.0: minor release — Brain unifies sent-email continuity across send paths, moves cognitive recall to multilingual embeddings, forces tagged learnings into context, hardens email loop guards and headless runners, exposes learning creation dates, and adds AUTO-N burst postmortems.

Previously in 7.14.0: minor release — Brain closes the install/reliability loop with update-path venv recovery, platform-gated wheels, WSL Desktop-managed flag preservation, startup memory authority warnings, legacy MEMORY write blocking, post-action real-world verification, and stale followup triage.

Previously in 7.13.9: patch release — Brain moves aside an existing managed .venv when it was created with unsupported Python <3.10, then recreates it with the supported interpreter prepared by Desktop.

Previously in 7.13.8: patch release — Brain rejects Python <3.10 during Desktop-managed fresh installs, honors the Python interpreter prepared by Desktop, and fails clearly before dependency resolution if an unsupported Apple Python 3.9 reaches the installer.

Previously in 7.13.7: patch release — Brain adds an authenticated official protocol-card client (nexo_card_catalog, nexo_card_get, nexo_card_match) so agents can ask the NEXO Desktop backend for the right task protocol at runtime. The protocol corpus stays private on the server; this open-source package ships only the client, tool map, and agent guidance.

Previously in 7.13.6: patch release — Codex hook sync now renders the managed PreToolUse shell/exec_command guard with native Windows cmd.exe syntax while preserving the existing POSIX command on macOS/Linux. Result: coordinated Desktop bundles can ship the fixed Brain without changing the Mac/Windows installation contract.

Previously in 7.13.3: unified release — doctor now repairs orphan personal script metadata and ignores historical versions/** snapshots, nexo update prunes runtime snapshots older than two back, protocol compliance self-heals missing task-open/change-log/stale-session gaps, headless automation uses bounded timeouts, Guardian false positives are tightened, and Codex CLI config/default checks are release-gated. Result: coordinated Desktop bundles can ship the new Brain without changing the Mac/Windows installation contract.

Previously in 7.12.15: patch release — same-version packaged updates now still run the safe maintenance path, Deep Sleep clears process locks on shutdown, sent replies are recorded in durable continuity, and personal script schedule-marker drift is surfaced during reconcile. Result: coordinated Desktop bundles can refresh Brain safely without breaking install/update parity on macOS, Windows via WSL, or Linux.

Previously in 7.12.0: minor release — adds nexo support-snapshot for generic local runtime diagnostics and completes the silent-reminder hardening on the live Protocol Enforcer path. The support collector emits one JSON bundle with version/platform metadata, runtime path presence, health-check output, and recent event/operation tails, while map-driven reminders (nexo_startup, nexo_smart_startup, nexo_heartbeat, nexo_reminders, nexo_session_diary_*, nexo_stop, nexo_task_close, compaction checkpoint prompts) now say explicitly that silence owns the entire reminder turn.

Previously in 7.11.5: patch release — Desktop-managed installs now block the standalone dashboard at the same product-mode layer as evolution, so installation_live, cron sync, and watchdog no longer disagree about whether com.nexo.dashboard should exist. Validation: 125 targeted tests across product-mode, cron sync, and doctor, plus a full pre-release wrapper (2321 passed, 2 skipped, 1 xfailed, 4 xpassed).

Previously in 7.11.4: patch release — packaged runtimes now receive root JSON contracts such as local_model_manifest.json, install/update paths sync core crons from src/crons/manifest.json instead of depending on a stale JS list, runner-health-check is wired into cron/doctor/dashboard instead of writing an unread file, and the watchdog retries failed crons immediately while treating run_once_on_wake as catchup-style recovery. Validation: 117 targeted tests across packaged update, cron sync/recovery, dashboard, local models, and runtime update contracts.

Previously in 7.11.3: patch release — root-cause fix for the mcp_restart_required lockup that v7.11.2 only masked at the enforcer layer. _FINGERPRINT_EXCLUDE_DIRS in src/runtime_versioning.py was missing "versions", so compute_mcp_runtime_fingerprint() walked into core/versions/<old>/**.py whenever it was called against the live runtime root. installed_runtime_fingerprint() (which resolves through active_runtime_root() → core/versions/<active>/) returned a clean per-snapshot hash, while prime_process_fingerprint() (which starts from Path(__file__).resolve().parent → live core/) accumulated every retained snapshot. The two never matched after the second-ever nexo update on a host. Every update wrote mcp-restart-required.json and the marker could never be cleared by _ack_current_client_if_restarted() because the installed_fp != process_fp test always returned True. Every non-allowlisted MCP tool (nexo_reminders, nexo_smart_startup, nexo_guard_check, nexo_task_open, …) returned {"error": "mcp_restart_required", "reason": "fingerprint_mismatch"} indefinitely, even after the operator restarted the client. Adding "versions" to _FINGERPRINT_EXCLUDE_DIRS restores parity; 21 runtime-fingerprint tests stayed green.

Previously in 7.11.2: patch release — two reliability fixes in the same family ("components ignoring signals they should respect"): (1) STUCK CRON REAPER added to nexo-watchdog.sh and (2) the Guardian/Enforcer now honors the mcp-restart-required marker. The watchdog reaper closes the v5.8.1 in-flight gap: truly hung wrappers (e.g. headless claude --bare blocked on an MCP that flagged mcp_restart_required) used to hold their slot for days. The reaper sweeps cron_runs rows with ended_at IS NULL past stuck_after_seconds (per-cron from manifest.json, fallback 12h global), SIGTERMs the wrapper (trap closes row at exit 143), grace 10s, SIGKILL on survivors. Generous defaults (deep-sleep 8h, sleep/evolution 4h) prevent any v5.8.1 regression. The enforcer gate skips nexo_*-mentioning reminders when the marker file is present (cached per-instance, 30s TTL); reminders that don't reference nexo_* still fire. 12 new tests; 3 existing watchdog tests + 52 existing enforcer tests stay green.

Previously in 7.11.1: patch release — caches the runtime fingerprint by (file_count, size_total, max_mtime) signature so MCP startup and the per-tool-call resolve_restart_required skip the 263-file rehash when nothing on disk changed. ~11× speedup warm path (~40ms → ~3.7ms locally), ~10-20s/day saved across Claude Code / Codex / headless / deep-sleep / cron startups. Cache miss is always safe (falls through to full hash and self-repairs). Default use_cache=False keeps plugins/update.py on the ground-truth path around git pull / npm update. Builds on the v7.11.0 runtime fingerprint that gates mcp-restart-required.json. Full write-up in docs/runtime-fingerprint.md.

Previously in 7.10.0: minor release — removes the LLM proxy override path that 7.9.28 → 7.9.34 introduced. Background: 7.9.28 added two opt-in files at ~/.nexo/config/llm_endpoint.json and ~/.nexo/config/auth_provider.json that let a third-party orchestrator (NEXO Desktop) redirect every Anthropic SDK call from Brain to a custom proxy and resolve the bearer via a local helper, with concrete model names translated to wire aliases (nexo-max, nexo-high, nexo-medium, nexo-low, nexo-mini) and an Idempotency-Key per request. NEXO Desktop's commercial model has changed: Desktop is now a wrapper over the user's own Claude Code subscription (Max / Pro), with a separate Desktop licence. Brain calls go directly to api.anthropic.com using the user's existing OAuth (the one stored under ~/.claude/ and consumed by Claude Code spawns) or a plain ANTHROPIC_API_KEY. There is no NEXO bearer, no NEXO proxy, no NEXO credit accounting in this codebase. Every proxy symbol is gone from call_model_raw.py and agent_runner.py; the proxy-specific tests and docs/api/override-files.md are removed; any pre-existing override files on disk are simply ignored from this release forward.

Previously in 7.9.34: two fixes — the email monitor's header parser was dropping any email whose RFC822 headers came back as email.header.Header instances (Q-encoded utf-8 / quoted-printable). Every msg.get(...) now goes through _decode_header, and the failure log is lifted from DEBUG to WARNING. The PreToolUse Guardian gate hardens hard blocks with stderr + exit 2 enforcement so terminal Claude cannot ignore the deny channel mid-tool-loop.

Previously in 7.9.33: adds usedforsecurity=False to the SHA-1 call that derives a filesystem-safe checkpoint filename from the email's Message-ID, so Bandit's B324 audit no longer fails the publish workflow on a non-security usage. The v7.9.32 git tag is preserved for traceability but no npm release ever shipped for it; nexo-brain@7.9.33 is the first release that carries the 7.9.32 email-recovery checkpoints.

Previously in 7.9.32: hardens the email monitor's recovery so emails that fall between Brain releases never end up in a permanent limbo. The periodic _recover_unreplied_processed sweep now looks back 7 days (was 24h), and every failed worker run persists a per-email checkpoint at ~/.nexo/nexo-email/checkpoints/ capturing files touched, last assistant narration, and error. Retry attempts inject that context into the next prompt so a long task (drafting a presentation, multi-step analysis) continues from where the previous attempt died instead of restarting from scratch. Stale checkpoints are pruned automatically after 7 days. 15 new unit tests cover the helpers.

Previously in 7.9.31: fixes a wire-level bug where call_model_raw was sending stop_sequences=["\n", ".", " "] by default, which the current Anthropic Messages API rejects with HTTP 400 each stop sequence must contain non-whitespace. The default is now None (no stop_sequences field sent) since max_tokens=3 already caps the yes/no classifier output. A local guard rejects whitespace-only caller values up front so the error shows where the caller is, not as a remote 400. Also removes an internal design document that did not belong in the open-source distribution.

Previously in 7.9.30: hotfix for a missing import sys in src/agent_runner.py that ruff F821 caught in CI and blocked the 7.9.29 publish workflow before any npm artifact shipped. nexo-brain@7.9.30 is the first npm release that carries the 7.9.29 override-path hardening.

Previously in 7.9.29: hardening pass on the optional LLM endpoint and auth provider override path. The bearer is now passed to the Anthropic SDK via auth_token so it lands in the standard Authorization: Bearer header (7.9.28 sent it as X-Api-Key and any compatible proxy rejected every request with 401). The Brain config directory is resolved on each call instead of cached at import, so LaunchAgent crons that export NEXO_HOME via a wrapper now reach the right ~/.nexo/config/. The Idempotency-Key header accepts a caller-provided value so application-level retries reuse the same dedup key. Override mode is strict about its bearer source: if auth_provider.json is missing or the helper fails, the call raises ClassifierUnavailableError instead of falling back to the operator's real ANTHROPIC_API_KEY, which would otherwise leak to the custom proxy as a second header. A new end-to-end test suite drives the real SDK against a local http.server and asserts on captured wire headers and body, complementing the SDK-mock unit tests.

Previously in 7.9.28: optional override files at ~/.nexo/config/llm_endpoint.json and ~/.nexo/config/auth_provider.json let third-party orchestrators redirect Brain's Anthropic SDK calls and delegate bearer token resolution to a local command (analogous to git's credential.helper). The same redirection is propagated to every CLI child Brain spawns (deep-sleep, evolution, followup-runner, morning-agent, email-monitor, nexo chat) by injecting ANTHROPIC_BASE_URL and ANTHROPIC_API_KEY into the spawned environment, so headless crons reach the proxy too. An Idempotency-Key (UUID4 hex) is attached per request for proxy-side dedup of transparent retries within 24h. Brain libre standalone (no override files) hits api.anthropic.com directly with ANTHROPIC_API_KEY exactly as before.

Previously in 7.9.27: server startup no longer hangs the MCP initialize handshake when legacy followups/reminders still need owner backfill — the synchronous startup migration now runs --rules-only and skips the multi-minute LocalZeroShotClassifier load, keeping handshake under a few seconds.

Previously in 7.9.26: headless automation prompts now receive the operator-language contract centrally, so reports, diaries, syntheses, followups, escalations, and Deep Sleep-generated memory text follow calibration even when the underlying template is English.

Previously in 7.9.23: Desktop lifecycle fallback diaries now enrich sparse lifecycle events from continuity snapshots, so app-exit fallback evidence preserves recent turn context even when the live agent does not answer the injected diary prompt before shutdown.

Previously in 7.9.22: Desktop lifecycle shutdowns gained an emergency Brain-side fallback diary path, so close/archive/app-exit can preserve title, goal, session ids, and transcript tail even when the live agent does not answer the injected diary prompt before shutdown.

Previously in 7.9.21: LaunchAgent reload/repair now handles macOS already-loaded races by booting out jobs with modern launchctl forms, falling back to legacy load, and treating an already-loaded job as healthy only when it points at the expected plist.

Previously in 7.9.20: packaged update/doctor repair now finds runtime/crons/sync.py, LaunchAgent PATH includes the managed Claude runtime installed under ~/.nexo/runtime/bootstrap/npm-global/bin, root runtime backfill includes claude_cli.py, and Immune no longer treats the legacy optional ~/.claude-mem/claude-mem.db as a required database.

Previously in 7.9.19: runtime doctor now distinguishes real install breakage from tracked in-progress work, interactive Desktop sessions no longer poison automation telemetry scoring, stale filesystem skill rows are pruned during sync, stale protocol debt draining marks rows resolved, and watchdog treats LaunchAgent SIGTERM reloads as supervisor interruptions instead of failures.

Previously in 7.9.18: packaged client-sync imports now work when NEXO_HOME is unset, so nexo clients sync, nexo update, and runtime doctor bootstrap checks no longer hit the _user_home import-order crash.

Previously in 7.9.17: continuity snapshot idempotency marks its SHA-1 digest as non-security usage, keeping the high-severity Bandit gate green while preserving stable idempotency keys.

Previously in 7.9.5: patch release that fixes canonical diary confirmation for Desktop: Brain resolves the Desktop/Claude session UUID through NEXO SID aliases before checking session_diary, so archive/delete/app-exit can confirm diaries written by nexo_session_diary_write under the active nexo-... SID. Verification: pytest tests/test_lifecycle_events.py (28 passing) plus coordinated Desktop v0.28.6 shutdown/archive/delete/app-exit checks.

Previously in 7.9.4: patch release that blocks the Brain 7.9.3 + Desktop 0.28.2 diary regression: canonical lifecycle plans now require real session_diary evidence (wait_for_diary_write) before stop_session, and canonical completion is rejected/retryable without that diary row. It also fixes npm CLI onboarding so nexo-brain --version and subcommands never launch the wizard when legacy/v2 calibration is already valid, commits setup calibration atomically only after the wizard completes, and adds nexo-brain warmup-models so install/update paths predownload the local mDeBERTa/BGE/reranker models. Verification: full Brain pytest (2189 passed, 3 skipped, 1 xfailed, 5 xpassed), release-readiness, npm pack dry-run, and coordinated Desktop v0.28.3 checks.

Previously in 7.9.3: patch release that hardens Brain's canonical lifecycle plan for Desktop close/archive/delete/app-exit diary guarantees: canonical_actions now publish the v2 canonical shape (type plus payload.prompt) while keeping one-release compatibility mirrors (kind plus top-level prompt) for older Desktop clients. This lets Desktop execute resume → diary prompt → stop with one exact owner per lifecycle event and preserve Brain-side dedupe by event id. Targeted verification: pytest tests/test_lifecycle_events.py (25 passing) plus release-readiness after artifact sync.

Previously in 7.9.2: patch release that completes the Brain semantic-router site migration: the remaining decision callers now route through semantic_router.route(...) with named decision_kind policies (r20_constant_change, r34_identity_coherence, t4_r15, t4_r23e, t4_r23f, t4_r23h, followup_operator_attention, drive_signal_type, drive_area, reply_event_type, query_intent, and sentiment_intent). Brain now owns model choice, thresholds, and fallback behaviour centrally instead of each caller carrying its own classifier policy. The patch also fixes packaged headless Guardian map loading: enforcement_engine and agent_runner now check the installed core directory (~/.nexo/core/tool-enforcement-map.json) so followup-runner, morning-agent, digest, and email-monitor load the map instead of falling back to unguarded subprocess execution. Targeted verification: 100 semantic/router/enforcer tests, 125 Drive/cognitive/productization tests, and release-readiness passing.

Previously in 7.9.0: minor release that ships the foundation of the semantic stack (router + reasoner + CLI) under the ONEPASS LLM Coverage plan, plus two product-bug fixes observed in the wild on 2026-04-23. New src/semantic_router.py exposes 18 named decision_kinds (13 textual + 5 code-aware) with a per-kind policy table and the layer chain fast_local → semantic_reasoner → remote_fallback. New src/semantic_reasoner.py adds Mode A (multipass_local: reuses the mDeBERTa pin with three prompt-perturbed passes + majority vote + 0.75 floor) and Mode B (cached_llm: wrapper over call_model_raw with a pid+uuid atomic-write 24h-TTL disk cache at ~/.nexo/runtime/operations/semantic-reasoner-cache.json, SHA-256 keyed by decision_kind + normalized input, LRU-bounded at 2000 entries, corrupt entries dropped on read). New scripts/semantic-classify.py JSON-in JSON-out CLI lets external MCP clients (including the closed-source NEXO Desktop companion) query Brain as the single semantic authority. New NEXO_SEMANTIC_REASONER kill switch (0/off/false/no/disable/disabled) honours the plan mandate for a runtime opt-out separate from NEXO_LOCAL_CLASSIFIER. Bug fixes: bin/nexo-brain.js upgrade flow now copies templates/ root the same way fresh install and same-version refresh already did (Maria iMac 7.1.10→7.8.1 upgrade had lost 27 core-prompts templates and broken post-update import verification); and tool-enforcement-map.json nexo_startup.enforcement.inject_prompt now instructs the model to preload the 13 mcp__nexo__* protocol tools via ToolSearch before calling nexo_startup when the host MCP client defers tool schemas (Claude Code with many MCPs installed). Audit-driven hardening: router/reasoner defensively use getattr over the call_model_raw module and add a trailing except Exception so provider errors degrade with remote_error instead of propagating; cache writes use pid+uuid tmp + fsync + os.replace to survive concurrent writers; NEXO_SEMANTIC_REASONER_TTL parse tolerates malformed values. Tests: +50 (22 router, 20 reasoner, 8 CLI). Per-site migration of existing callers (session_end_intent, r14, r16, r17, r20, r34, T4 gates, tools_drive, nexo-followup-runner) is explicitly deferred to follow-up patch releases and tracked as NF-SEMANTIC-ROUTER-SITE-MIGRATION; nothing in this release changes the behaviour of the existing callers. Companion coordinated release: NEXO Desktop v0.28.0.

Previously in 7.8.2: patch release that fixes the compact-hook observability gap Francisco flagged after v7.8.1: hook_runs.session_id was empty for 7 out of 8 recent compaction rows (and when populated it stored the raw Claude Code token instead of the NEXO sid), so per-session queries over hook_runs for compact events could not be joined back to the NEXO session that actually compacted. v7.8.2 adds src/hooks/compact_session_resolver.py with resolve_nexo_sid(claude_session_id), which walks the same rails the shell already uses: sessions.claude_session_id match, then session_claude_aliases.claude_session_id (most recent last_seen wins), then the per-conversation sidecar under runtime/data/compacting/<safe-claude-id>.txt, then the legacy global sidecar for single-conversation setups. src/hooks/pre_compact.py and src/hooks/post_compact.py now call the resolver and store the real NEXO sid in hook_runs.session_id; both wrappers also stash {claude_session_id, sid_source} in hook_runs.metadata so "why is this row still empty?" has a one-query answer. Nine new tests in tests/test_hook_runs_compact_sid_resolution.py pin the five resolver rails (sessions / alias / sidecar / legacy / none), malformed-sidecar rejection, the pre- and post-compact wrapper end-to-end paths, and the empty-state wrapper rail so a clean audit trail is written even when nothing resolves. No Desktop bump.

Previously in 7.8.1: patch release that closed the last compaction-continuity gap Francisco flagged after v7.8.0: pre-compact.sh Layer 2 emergency auto-diary and Layer 3 compaction_memory.record_auto_flush now use the exact TARGET_SID resolved from CLAUDE_SESSION_ID instead of falling back to ORDER BY last_update_epoch DESC LIMIT 1 ("latest active session"). In multi-conversation Desktop that fallback routinely wrote the emergency diary against the wrong conversation even though the main restore path was already exact-SID in v7.8.0. last_diary_ts is also scoped by session_id now. Fail-closed when no CLAUDE_SESSION_ID resolves. New behavioural tests drive the real shell script with two sessions in the DB to pin the invariant. Fixed a latent bash-escape bug in pre-compact.sh where a double-quoted string inside a Python comment silently closed the python3 -c "..." argument early — caught by adding the behavioural tests. Pytest 2092 passing (+2 new behavioural). No Desktop bump.

Previously in 7.8.0: minor release that closed the PostCompact continuity work Francisco requested after v7.7: src/hooks/post_compact.py is a real registered hook (part of the canonical 9-hook set, was 8), pre-compact.sh resolves the exact NEXO SID from CLAUDE_SESSION_ID instead of falling back to "latest active session" (that was actively wrong in multi-conversation Desktop), the sidecar moves from /tmp to $NEXO_HOME/runtime/data/compacting-sid.txt so two concurrent compactions on two conversations cannot race on /tmp, post-compact.sh removes its "latest checkpoint" fallback (fail-closed to a diagnostic systemMessage instead of restoring the wrong conversation), and the hook cross-checks the sidecar SID against the env-resolved one so a "SID mismatch" is logged as such. Pre- and post-compact now emit NDJSON events the engine drains on every periodic tick via _consume_pending_hook_events(); the queue file is truncated after read so an event never fires twice. A new contract test (tests/test_v78_compaction_continuity.py) pins 11 invariants across ten rails including the hook registration, the exact-SID resolution path, fail-closed behaviour, and that compaction_count only increments on real restore. Pytest 2086 passing (+16 vs v7.7). No Desktop bump — v0.27.0 continues to ship.

Previously in 7.7.0: minor release that closed the six gaps left partial after v7.6.0's constructor-guardian-90 pass 1 (autonomous detector for multi_step_task_detected, R16 vocabulary expansion, R_CATALOG extended to plain Edit/Write, new R_PRIMITIVE_CHOICE rule, R11_plugin_load_pre_inventory hardened, 12 new contract tests). Post-review hotfix on the same release wired task_open rearm properly (discarded from tools_called + per-instance pin cleared on task_close), added live on_event triggers in R14 and R16, and called on_tool_call_before before on_tool_call in run_with_enforcement so before_tool rules fire in Brain the same way Desktop fires onBeforeToolCall.

Previously in 7.6.0: minor release that closed the drift between tool-enforcement-map.json v2.2 and the two enforcement engines (Brain Python + Desktop JS), added per-instance after_tool satisfaction, tightened learning_add grace to 0 and task_open threshold to 4/must, hardened R15/R17/R22/R_CATALOG from soft to hard, and raised R34 from shadow to soft.

Previously in 7.5.0: minor release that promoted nexo_lifecycle_event from ledger + reconciliation authority to canonical authority of session-end. Brain now owns the prompt, the sequence, and the timing of diary+stop; Desktop v0.25.0 (closed-source companion) is the conduit that executes Brain's plan against the live Claude process. The new 2-call contract — nexo_lifecycle_event returns a versioned canonical_plan (resume_session → inject_prompt → stop_session, with stable ids and per-action timeouts) and nexo_lifecycle_complete_canonical confirms execution with a per-action results array — replaces polling with explicit acknowledgement. canonical_plan_id is deterministic: sha256(event_id + "|v" + plan_version)[:24], so retries reuse the same id. Migration m52 extends lifecycle_events with six canonical_* columns plus an index; pre-v7.5 rows simply carry NULL. session_diary is the dedupe key on re-delivery: if Desktop crashes between executing the inject and sending the complete call, the next nexo_lifecycle_event for the same event_id checks for a diary written after canonical_dispatched_at; if one exists, Brain short-circuits to already_processed and refuses to re-dispatch. The seven explicit delivery_status values (accepted, processed, canonical_pending, canonical_done, already_processed, retryable_error, rejected) give the pipeline a diffable state machine. switch and window-close stay observational (no plan ever issued, even with a live session_id). nexo lifecycle record now returns exit code 0 for canonical_pending; older wrappers that treated it as an error are incompatible with v7.5. MCP tool count: 262 → 263.

Previously in 7.4.1: patch release correcting the over-promise in v7.4.0's release notes and locking in the exact role of nexo_lifecycle_event as a ledger + reconciliation authority — NOT the canonical executor of diary+stop, which lived in Desktop. That responsibility moved to Brain in v7.5.

Previously in 7.2.0: minor release consolidating three parallel workstreams into a single Guardian-active-by-default train. Block K roadmap closure (G1 enforcer active, G3 SSH remote-write detector, src/guardian_runtime_config.py resolver, _persist_guardian_hard_defaults during nexo update). F0.6 hardening wave (nexo rollback f06 CLI, src/scripts/prune_runtime_backups.py promoted to core, docs/f06-layout-contract.md, three new doctor boot-tier checks, scripts/nexo-migrate-nora.sh + scripts/f0-safe-apply-remote.sh idempotent migration). Adaptive weights flipped from "14-day calendar wait" to "14 days OR (≥200 samples AND ≥2 days)" with auto-promotion during nexo update. Small-fixes batch: R34 bool("unknown")==True fix, classify_scripts_dir dedup, B10 module-level path constants lazy-evaluated, schedule override audit log, scripts/pre-release-verify.sh + docs/release-discipline.md, pre-commit hook that blocks commits when tool-enforcement-map.json drifts from src/plugins/.

Previously in 7.1.10: follow-up over v7.1.8 that shipped two rescue batches of WIP stashed aside during the v7.1.8 release window. First rescue: src/autonomy_mandate.py expanded the mandate-detection vocabulary (hazlo todo / no pares / estás al mando / te dejo al mando / sigue sin parar / haz el plan completo), added three honest flags on MandateState (execute_until_blocker, suppress_mid_task_menus, revalidate_after_compaction) with session filtering, wired post/pre-compact hooks that read those flags, surfaced them through protocol/workflow handlers and session payload, and introduced the new src/checkpoint_policy.py module with tests. Second rescue: scripts/verify_release_readiness.py gained a smoke-artifact contract pass that validates release-contracts/smoke/v<version>.json before any tag push, the release-final audit skill references the new contract, src/hook_guardrails.py + src/hooks/post_tool_use.py refine the post-tool protocol reminder path with a new contract test, and a couple of core prompts (task-close evidence, r14 correction learning) got wording polish.

Previously in 7.1.8: batch release over v7.1.7 consolidating the Block K Guardian/Enforcer roadmap (auto-drain of stale protocol_debt rows, destructive-command pre-tool gate, guard_check-required gate, inline guard ack on nexo_task_open, Guardian Health in the morning briefing) with Block D hardcode cleanup (classifier-backed backfill_task_owner, migration v50 supersedes the duplicate NEXO-product learning pair, new semantic-hardcodes audit) and Block E product guards (LaunchAgent plist protection, agent-name fallbacks no longer leak the product identity, francisco_emails removed from the email-config dict export, runner-health-check.py + nexo_personal_automation.py promoted from personal to core).

Previously in 7.0.1: hotfix over v7.0.0 (db._core.DB_PATH was only caller still hardcoded to legacy ~/.nexo/data/nexo.db; every shared-DB command silently returned empty results post-migration). Previously in 7.0.0: BREAKING — Plan Consolidado fase F0.6: physical separation of the runtime tree into ~/.nexo/{core,personal,runtime}/. The flat layout (~/.nexo/scripts/, brain/, data/, operations/, ...) is gone. Operators on v6.x are auto-migrated on first nexo update; fresh installs land directly in the new tree. New paths.py helpers are transition-aware.

Previously in 6.5.0: Plan Consolidado fase F0.2: operators can now nexo scripts enable|disable|status <name> any personal automation. The cron wrapper honours the flag at every tick (exit 0 with summary='[disabled]' while the LaunchAgent stays loaded). The companion NEXO Desktop client (a closed-source product, distributed separately) wires the same toggle into its Automatizaciones panel. See CHANGELOG for the full diff.

About NEXO Desktop. NEXO Desktop is a separate closed-source companion app distributed at nexo-desktop.com — its source does not live in this repo. When release notes mention Desktop they describe a coordinated client release that consumes the Brain's CLI / MCP contract; the Brain itself is fully usable on its own (terminal, Codex, Claude Code, or any MCP client). If you want the product edition rather than the open-source Brain alone, contact info@wazion.com and ask about NEXO Desktop.

Previously in 6.4.0: Plan Consolidado fase F1 — multi-tenant email accounts (email_accounts table, nexo email setup interactive wizard, nexo email add --password-stdin --json for machine consumers, idempotent migrator from legacy ~/.nexo/nexo-email/config.json). On post-F0.6 installs that legacy-looking path is only a compatibility alias/shim into ~/.nexo/runtime/nexo-email/config.json; it should never be treated as a second source of truth.

Previously in 6.3.1: privacy hotfix over v6.3.0. The nightly auditor caught that src/presets/entities_universal.json in v6.3.0 shipped operator-specific vhost_mapping entries (private IPs, hostnames, tenant names). v6.3.1 pulls those out into src/presets/entities_local.sample.json (template) + .gitignore'd ~/.nexo/brain/presets/entities_local.json (operator copy), and the installer drops the sample at nexo init. No behaviour change on the Guardian side.

Previously in 6.3.0 — Plan Consolidado wave 2, coordinated with NEXO Desktop v0.18.0. Closes the remaining Guardian roadmap items that do not require an invasive structure migration: extended cognitive_sentiment shape (is_correction/valence/intent), extended entities schema, 21 labelled rule fixtures with R13 spike gates, Fase F telemetry loops + Deep Sleep phase, pinned local zero-shot classifier skeleton (mDeBERTa), hook respects NEXO_MIGRATING=1, origin column on personal_scripts, and the T4 LLM gate wrapping R15/R23e/R23f/R23h (byte-parity Py ↔ JS). Two pre-release auditors flagged a CRITICAL in the first JS wire (method-name + async mismatch) and a HIGH (classifier bool conflated "no" with "unparseable"); both corrected with regression tests before merge.

Previously in 6.1.1: small fix to nexo --help so the Latest: vX line reliably appears when NEXO Desktop invokes the CLI via subprocess — unblocks the Desktop Brain auto-update banner that previously couldn't parse the version delta. No behaviour change for interactive terminal users; the 6-hour registry cache still rate-limits network calls. Bundles all v6.1.0 Protocol Enforcer Fase 2 + multi-claude-sid hotfix content.

Previously in 6.0.2: adds the reserved caller prefix personal/* so scripts living in ~/.nexo/scripts/ can invoke the automation backend with their own caller id without editing src/resonance_map.py. New kwarg tier ("maximo" / "alto" / "medio" / "bajo") on run_automation_prompt, run_automation_interactive, nexo_helper.run_automation_text, nexo_helper.run_automation_json, and nexo-agent-run.py --tier. Precedence for personal/* callers: explicit tier= → explicit reasoning_effort= → calibration.preferences.default_resonance → DEFAULT_RESONANCE (alto). Registered callers keep their behaviour unchanged. New guide: docs/personal-scripts-guide.md.

Previously in 6.0.1: hotfix on top of the 6.0.0 release. protocol_settings.py now treats the process as interactive when either stdin+stdout are TTYs or NEXO_INTERACTIVE=1 is exported — closes the gap where NEXO Desktop 0.12.0 spawned claude through pipes and Brain fell back to lenient even with a human in the loop. The PostToolUse hook also gains an inbox autodetect stage: when the session has unread nexo_send messages and has gone 60s+ without a heartbeat, it emits a systemMessage asking the agent to run nexo_heartbeat and consume them. Rate-limited to one reminder per minute per SID (new hook_inbox_reminders table, migration m42). Added sessions.last_heartbeat_ts, stamped by every successful heartbeat. NEXO_INTERACTIVE is an internal Brain↔Electron contract — not user-facing, not a resurrection of the removed NEXO_PROTOCOL_STRICTNESS.

Previously in 6.0.0: BREAKING tier-only setup. Onboarding asks for one resonance tier (maximo/alto/medio/bajo) and that choice drives every backend via src/resonance_tiers.json; the per-backend model/effort prompts are gone and the legacy client_runtime_profiles.{claude_code,codex}.{model,reasoning_effort} are silently purged from schedule.json on upgrade. Protocol strictness is no longer configurable — interactive TTY sessions run strict, non-TTY (crons, pipes, tests) run lenient; NEXO_PROTOCOL_STRICTNESS env, preferences.protocol_strictness, and the default/normal/off/warn/soft aliases are all removed. preferences.show_pending_at_start moves to NEXO Desktop's electron-store. The seven core hooks are now unified behind src/hooks/manifest.json (plugin and npm modes read the same file), two new hooks ship (Notification for live-session activity and SubagentStop for auto-closing stale protocol_tasks), and auto_capture.py is wired to both UserPromptSubmit and PostToolUse with a persistent 1h dedup table plus an automatic nexo_learning_add on correction matches. ~/.nexo/hooks_status.json is published after every registerAllCoreHooks() so NEXO Desktop ≥0.12.0 can render Hooks activos X/Y. New nexo-brain --skip flag aliases --yes/--defaults. Full suite 1057 passed, 1 skipped.

Previously in 5.10.2: auto-bootstraps brain/profile.json from brain/calibration.json on nexo update when the profile file is missing, empty, or corrupt AND calibration carries at least one of meta.role, meta.technical_level, name, language. NEXO Desktop's Preferencias → Avanzado tab used to render an empty {} for that block when the onboarding flow had been interrupted; now it either shows the seeded profile or a friendly explanation of what each file is for, paired with Desktop v0.11.2 which adds header descriptions to both JSON blocks. Never overwrites a populated profile, never raises, idempotent. Also fixes a latent host-filesystem leak in test_user_facing_caller_with_no_user_default_uses_alto exposed by the v5.10.1 migration.

Previously in 5.10.1: silent, one-shot migration that recovers legacy reasoning_effort="max" (written by nexo preferences --reasoning-effort max before v5.9.0) into the new preferences.default_resonance map — any user who had configured max before v5.9.0 and never touched the new selector was silently falling back to DEFAULT_RESONANCE="alto" on interactive calls since the v5.10.0 update. _run_runtime_post_sync() runs _migrate_effort_to_resonance() exactly once: max→maximo, xhigh→alto, high→medio, medium→bajo. No-op when calibration or schedule already declares an explicit default_resonance; idempotent; conservative; never raises.

Previously in 5.10.0: fixes the deep-sleep extract bloat that made Session 1 take ~57 minutes on some installs (new bare_mode on run_automation_prompt wires claude --bare for JSON-only extractor callers — ~4.3× faster per child, sourced from ANTHROPIC_API_KEY env or ~/.claude/anthropic-api-key.txt). caller= is now mandatory on run_automation_prompt — no silent fallback; every automation subprocess traces back to a registered caller with a deliberate tier. Five personal scripts (personal/email-monitor, personal/github-monitor, personal/post-x, personal/followup-runner, personal/orchestrator-v2) joined the resonance map with tiers picked per caller based on what each one does. gbp/* marketing posts bumped from medio to alto (public-facing copy, quality first over speed). 65 legacy protocol debts bulk-resolved as part of the audit — the patterns that generated them are structurally closed by mandatory caller= + unified session log + bare_mode.

Previously in 5.9.1: adds default_resonance to brain/calibration.json via the Desktop-facing schema (nexo schema --json), so NEXO Desktop's Preferences dialog renders a select with Máximo / Alto (recomendado) / Medio / Bajo automatically — no Desktop release needed. resolve_tier_for_caller reads calibration first and falls back to the legacy schedule.json location. nexo preferences --resonance writes both. The UI control only affects interactive sessions (nexo chat, Desktop new conversation, interactive nexo update); crons and background processes stay pinned per caller in resonance_map.py.

Previously in 5.9.0: every Claude/Codex invocation now flows through a central resonance map and a unified session log. Four tiers (MAXIMO / ALTO / MEDIO / BAJO) each resolve to a concrete (model, reasoning_effort) pair per backend. User-facing callers (nexo chat, Desktop new conversation, interactive nexo update) honour the user's default_resonance preference; system-owned callers (deep-sleep, evolution, catchup, GBP posts, …) run at a fixed tier chosen per caller in src/resonance_map.py — the user's preference never downgrades a cron we decided needs MAXIMO. Unknown callers raise UnregisteredCallerError. Migration #41 adds caller, session_type, started_at, ended_at, pid, resonance_tier to automation_runs; interactive sessions record a row at spawn (with ended_at=NULL) and update it on close, so the Brain now has a single source of truth for every Claude/Codex call regardless of origin. New nexo preferences --resonance CLI. New MCP tools nexo_session_log_create / nexo_session_log_close let NEXO Desktop (which spawns claude directly from its TypeScript process) feed the same log.

Previously in 5.8.2: the Brain core no longer auto-classifies followups and reminders on behalf of agents. v5.8.0's classify_task() heuristic (NEXO-specific ID prefixes NF-PROTOCOL-* / NF-DS-* / NF-AUDIT-*, Spanish user-verbs debes / revisar / firmar, agent keywords monitor / auditoría diaria / checkpoint) was fine for NEXO's own DB but bled convention into every third-party agent plugged into the shared Brain. The core now persists internal=0 and owner=NULL when the caller omits them, and clients that want automatic classification (NEXO Desktop does, via its _legacyClassifyOwner helpers) compute it themselves and pass the result. Migration #40 keeps the columns + indexes; rows already backfilled by v5.8.0 keep their values. normalise_owner still explicitly rejects the string "nexo" so legacy hardcoding cannot sneak back in.

Previously in 5.8.1: closes a self-reinforcing launchctl kickstart -k loop in the watchdog that wedged deep-sleep Phase 2 between 2026-04-14 and 2026-04-17. The cron wrapper now INSERTs an in-flight row (ended_at=NULL) at start and traps SIGTERM/INT/HUP to close it with exit_code=143 instead of vanishing from cron_runs. The watchdog interprets in-flight rows as "currently running" and only re-executes after verifying the worker process is dead. extract.py classifies CLI failures into transient (overloaded_error, rate-limit, timeout, signal — retried next run) and deterministic (skipped after MAX_POISON_ATTEMPTS), and passes a slim shared-context (200 head lines + metadata) instead of the full 400+ KB dump. A new auto_update._heal_deep_sleep_runtime() repairs existing installs silently on the next nexo update: poisoned checkpoints, stale locks, dangling cron_runs rows, and bloated .watchdog-fails counters.

Previously in 5.8.0: first-class internal and owner columns on followups and reminders. Migration #40 adds both fields with an idempotent one-shot backfill, so the "who does this task belong to?" classification moves from client-side regex (Desktop) to persistent storage every MCP client shares. Taxonomy is intentionally generic — owner in {user, waiting, agent, shared} — so third-party agents plugging into the shared Brain can render whatever assistant label they carry without inheriting NEXO branding. nexo_reminder_create, nexo_reminder_update, nexo_followup_create, and nexo_followup_update gain optional internal and owner parameters that win over the default heuristic.

Previously in 5.7.0: nexo update now keeps Claude Code and Codex CLIs in lockstep with NEXO Brain itself. When the global @anthropic-ai/claude-code or @openai/codex packages are installed, the updater checks the npm registry and runs npm install -g <pkg>@latest in-line — so the terminal boot model stays aligned with the settings NEXO already wrote to ~/.claude/settings.json. Packages the operator never installed are skipped silently. Pass nexo update --no-clis to keep the terminal CLIs pinned.

Previously in 5.6.1: update-path hardening — 0-byte .db orphans from interrupted installs are now purged from ~/.nexo/ and ~/.nexo/data/ before the pre-update backup, and sync_claude_code_model() propagates the NEXO-recommended model into ~/.claude/settings.json whenever heal_runtime_profiles() migrates the claude_code default.

Previously in 5.5.5: data-loss guardrails + automatic self-heal. The updater now refuses to capture an already-wiped nexo.db into a pre-update-* snapshot (validated sqlite3.backup + pre-flight wipe guard + post-migration row-count gate), and an auto-heal restores data/nexo.db from the newest hourly backup on the next server boot when a wipe is detected. New nexo recover CLI + nexo_recover MCP tool.

Previously in 5.5.4: Deep Sleep no longer blocks on unparseable sessions — reduced retries, added a JSON escape hatch, and unified the automation subprocess timeout to 3h across all scripts via a single shared constant.

Previously in 5.5.3: CLAUDE.md CORE teaches the model to trust the Protocol Enforcer, so aligned backends stop rejecting heartbeat, diary, and checkpoint injections as suspected prompt injection.

Start here:

• 5-minute quickstart
• Workflow quickstart
• Runtime templates
• Recent memory fallbacks + live system catalog
• Supported client guides
• Docker setup
• Architecture visuals
• Memory classes
• Session portability
• Python SDK
• Reference verticals
• Measured compare scorecard
• Memory benchmark harness
• Public contribution guide

Every time you close a session, everything is lost. Your agent doesn't remember yesterday's decisions, repeats the same mistakes, and starts from zero. NEXO Brain fixes this with a cognitive architecture modeled after how human memory actually works.

Shared Brain Across Clients

Shared brain is now the baseline:

• Claude Code remains the recommended path because it still has the deepest hook integration and the most battle-tested headless automation surface.
• Codex is supported both as an interactive terminal client and as the background automation backend.
• Claude Desktop can point at the same local brain through MCP.

That means NEXO now manages not only the shared runtime and MCP wiring, but also the startup layer around it:

• nexo chat opens the configured client instead of assuming Claude Code forever.
• Claude Code and Codex both get managed bootstrap files:
  • ~/.claude/CLAUDE.md
  • ~/.codex/AGENTS.md
• Those files now use an explicit CORE / USER contract, so NEXO can update product rules in CORE while preserving operator-specific instructions in USER.
• For Codex specifically, nexo chat and Codex headless automation inject the current bootstrap explicitly, so Codex starts as NEXO even when plain global Codex startup is inconsistent about global instructions.
• Deep Sleep now reads both Claude Code and Codex transcript stores, so overnight analysis still works even when the user spends the day in Codex.

Versions 2.6.14 through 2.7.0 established the practical shared-brain baseline: managed Claude/Codex bootstrap, Codex config sync, transcript-aware Deep Sleep, 60-day long-horizon analysis, weekly/monthly summary artifacts, retrieval auto-mode, and the first measured engineering loop.

Versions 3.0.0 and 3.0.1 close the next execution gap:

• protocol discipline is now a runtime contract, not just instructions:
  • nexo_task_open
  • nexo_task_close
  • persistent protocol_debt
  • enforceable Cortex gates
• durable execution is now first-class:
  • resumable workflow runs
  • checkpoints
  • replay
  • retries
  • durable goals
• conditioned learnings on critical files are now real guardrails across Claude hooks, Codex transcript audits, and headless automation prompts
• repair/correction work now routes through canonical learning capture instead of depending on the model to remember to document after the fact
• runtime truth is stricter:
  • no more healthy-looking warning storms
  • no more silent Deep Sleep schema drift
  • keep-alive jobs report alive/degraded/duplicated honestly
• public proof is stronger:
  • measured compare scorecard
  • external and internal ablations
  • cost_per_solved_task
  • SDK/API/quickstart surface

Versions 3.1.7 through 3.2.0 close the recent-memory gap:

• recent operational continuity is now first-class through hot context and recent events
• the runtime can build a reusable pre-action bundle instead of reconstructing the last few hours from diaries and durable recall only
• when even that misses, NEXO now exposes raw transcript fallback tools for Claude Code and Codex session stores
• NEXO can now inspect itself through a live system catalog derived from canonical sources instead of relying only on stale docs or operator memory

Version 5.3.11 hardens protocol and Cortex contracts: malformed outcome, task_type, and impact_level values now fail explicitly instead of being coerced into other valid states, so persisted task history, debt, hot context, and decision telemetry stay faithful to what the caller actually asked for. Version 5.3.10 tightened the packaged-runtime truth layer again: installs and updates now keep ~/.nexo/package.json aligned with the published npm package so runtime metadata and doctor evidence no longer drift to an old version, nexo doctor --tier deep treats a missing self-audit-summary.json as a pending bootstrap artifact when the runtime was just installed or updated instead of reporting a false degradation, weekly Evolution now asks for explicit dimension_scores / score_evidence so telemetry can persist instead of staying blank, and daily synthesis only ingests update-last-summary.json when it carries actionable runtime signals. Version 5.3.9 is the packaged core-artifact manifest heal for 5.3.8: packaged updates now rebuild runtime-core-artifacts.json from the canonical npm package src/ tree instead of scanning the live ~/.nexo/scripts directory, script classification prefers that canonical packaged source when available, and runtime doctor syncs personal scripts before LaunchAgent inventory so personal automations recover cleanly instead of being mistaken for unknown core drift. Version 5.3.8 was the immediate packaged-migration hotfix for 5.3.7: the installer/runtime migrator now discovers all top-level runtime Python modules from src/ dynamically instead of relying on a manual allowlist, so new product surfaces like nexo export / nexo import actually arrive in ~/.nexo after update instead of being present only in the published npm tarball. Version 5.3.7 closed the remaining packaged-runtime happy-path gap and finally exposed portable user-data migration commands: packaged nexo update now self-heals cron definitions and LaunchAgents after a successful npm bump, new nexo export / nexo import commands move operator data as a safe bundle instead of leaving that flow implicit, and runtime doctor now distinguishes tracked historical Codex drift from an actually broken runtime so cleaned installs stop staying red for stale transcript debt alone. Version 5.3.6 hardened the Claude Code bootstrap path and related runtime hygiene: managed client sync now writes the NEXO MCP server where current Claude Code actually reads it (~/.claude.json), script classification is stricter about core-vs-personal runtime artifacts, schedule status distinguishes genuinely running jobs from broken ones, and retroactive learnings stop opening keyword-only false positives outside their declared applies_to scope. Version 5.3.5 already keeps CLI version visibility honest right after nexo update: if the cached npm version lags behind the runtime you just installed, nexo / nexo chat now clamp Latest to the installed version and refresh the cache instead of showing a stale older release. Version 5.3.4 already cleaned up legacy core alias leakage and added the version-status banner. Version 5.3.3 closed the remaining packaged-runtime doctor mismatch: the built-in hourly backup helper is now inventoried as a core LaunchAgent, so clean installs no longer get a false unknown-LaunchAgent warning. Version 5.3.2 already hardened the runtime boundary by persisting which runtime scripts/hooks are core product artifacts, keeping nexo scripts from mixing those into the personal bucket, and migrating the legacy Claude Code heartbeat wrappers into managed core hooks.

Version 5.3.1 normalizes packaged npm installs so they behave like packaged npm installs: nexo update now keeps the runtime anchored to ~/.nexo, refreshes packaged bootstrap/client artifacts after upgrade, avoids repo-only release-artifact drift in installed runtimes, and keeps personal scripts on the canonical packaged path.

Version 5.3.0 adds nexo uninstall — a CLI command that cleanly separates runtime from user data. It stops all crons, removes the MCP server config, and preserves databases, learnings, and personal scripts for safe reinstall.

Version 5.2.1 fixes the Deep Sleep datetime regression and closes the decision-to-outcome feedback gap:

• _parse_any_datetime in apply_findings.py now strips timezone info before comparison, fixing the offset-aware/offset-naive crash that was breaking Deep Sleep verification work.
• cortex_decide() now auto-creates a decision_outcome when none is linked yet, so the outcome-checker cron can verify real decisions instead of leaving the loop open.

Version 5.2.0 closes two focused gaps in the Cortex layer that were left open by the v5.1 audit — the high-stakes response-contract detector was English-only, and the nexo-cortex-cycle cron was writing a quality snapshot that no reader ever consumed:

• HIGH_STAKES_KEYWORDS_ES adds ~45 Spanish keywords to the high-stakes detector with accented and unaccented variants, so a goal written in Spanish (migrar la base de datos de producción) trips the same gate as its English twin.
• NEGATION_PATTERNS suppresses false positives when the user explicitly disclaims touching the sensitive area (sin afectar producción, no tocar prod, without touching production, don't modify). The raw keyword being present is no longer enough to flag the task.
• evaluate_response_confidence accepts two new optional kwargs, pre_action_context_hits (+up to 10) and area_has_atlas_entry (+5), so the score can finally reward tasks that loaded real context instead of only punishing unprepared ones. Both signals are capped and cannot override a real risk penalty.
• A monotonic numeric safeguard layers on top of the boolean decision tree: answer downgrades to verify when final_score < 50, and verify downgrades to defer when high_stakes and final_score < 30. The safeguard can only make response discipline stricter, never looser.
• handle_cortex_quality in src/plugins/cortex.py now reads $NEXO_HOME/operations/cortex-quality-latest.json when the requested window (7 or 1 days) is fresh (<6h 30m) and the schema matches — silent fallback to the live SQL computation on any failure. The handler's JSON response now includes "source": "cache" | "live" for observability.

Version 5.1.0 lands the full NEXO-AUDIT-2026-04-11 roadmap as a single minor bump — every open evolution / adaptive / cognitive / skills loop now closes under itself, the knowledge graph exports cleanly, OpenTelemetry spans can be turned on without a hard dependency, and every PR has to clear lint, security, coverage, and release-readiness gates before it can merge:

• Evolution cycle now auto-applies user-approved proposals on the next run (backed by the new idempotent migration m38), adaptive learned-weight rollbacks surface as visible followups, outcome patterns auto-promote to draft skills, and a Voyager-style detector exposes co-occurring skill pairs as composite-skill candidates via nexo_skill_compose_candidates.
• cognitive._search.search() now accepts dream_weight and reranks dream-insights through it, somatic markers fold into the same reranking path (max +0.10 boost), state watchers open and auto-resolve deterministic NF-WATCHER-{id} followups, and correction fatigue opens a visible followup instead of only decaying memory.
• A new Cortex quality cron (every 6h) watches accept rate / linked-success / override gap and opens NF-CORTEX-QUALITY-DROP idempotently when the decision engine starts drifting between cycles.
• Adding a new learning now walks recent decisions through retroactive_learnings.apply_learning_retroactively() and opens deterministic NF-RETRO-L<id>-D<id> followups for every decision the learning would have changed (exposed via nexo_learning_apply_retroactively).
• Hook lifecycle observability: new hook_runs table (migration m39) + nexo_hook_runs tool expose recent hook runs, failure streaks, and a health summary. Hook drops are no longer invisible.
• Knowledge graph bitemporal export: nexo_kg_export emits JSON-LD (with an nexo:* vocabulary) or GraphML, and accepts an as_of ISO timestamp that replays the historical snapshot through kg_edges.valid_from / valid_until for igraph, Gephi, NetworkX, and Cytoscape.
• OpenTelemetry integration: new src/observability.py soft-imports opentelemetry and only activates when OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_SERVICE_NAME is set. tool_span() becomes a real span when enabled and stays a no-op context manager when disabled.
• CI gates on every PR: new workflows enforce ruff (E9 / F63 / F7 / F82 / F821), bandit at high severity / high confidence, coverage baselines, and verify_release_readiness.py --ci. A PR that breaks the release contract fails loudly instead of waiting until tag push.
• Safer update path: auto_update is guarded by a POSIX flock with stale-steal at 10 minutes, and on macOS it now launchctl unloads and reloads every com.nexo.*.plist after a version bump so long-lived crons pick up the new codebase immediately.

Version 5.0.4 tightens the local runtime bridge and trims false-positive doctor noise:

• vendorable nexo_helper.py now resolves NEXO_HOME and the nexo CLI path robustly, so personal scripts and subprocess flows stop depending on a lucky PATH
• doctor no longer degrades because of advisory-only self-audit warnings or a single missing usage-telemetry row
• managed Claude Code and Codex bootstraps now force an immediate first answer after simple email/diary/reminder/followup reads instead of feeling hung while chaining extra lookups

Version 5.0.3 closes the next post-5.0 runtime gap:

• nexo chat now boots Claude Code and Codex with an explicit NEXO startup prompt instead of opening cold or leaking the target path as a fake prompt
• terminal launches now use the requested working directory as real cwd, so the selected project path stops behaving like chat text
• the vendorable nexo_helper.py bridge now bounds helper calls with a timeout instead of letting personal-script subprocess flows wait forever
• the doctor hardening from 5.0.2 remains validated on a real upgraded runtime after sync

Version 5.0.2 closes the small post-5.0.1 doctor drift:

• deep doctor now reads the live learnings schema correctly whether the install uses status or the older archived flag
• a real upgraded runtime was revalidated with nexo update, nexo doctor --tier deep, nexo doctor --tier all, and a fresh Claude Code startup smoke

Version 5.0.1 hardens the live 5.0 upgrade path:

• managed Claude Code hooks are now cleaned up when an older release left obsolete core-managed entries behind
• upgrades no longer preserve the stale heartbeat-guard.sh path that could create warning storms and fake "hung" symptoms after nexo update
• the corrected path has been revalidated on a real install with nexo clients sync, Codex/Claude Code headless runtime access, email-monitor recovery, and a full nexo update

Version 5.0.0 closes the loop between memory, decisions, outcomes, and reusable behavior:

• goal profiles are now explicit and auditable instead of living as hidden heuristics
• the Cortex can rank alternatives with goals, outcomes, overrides, and structured penalties
• repeated outcome patterns can become durable learnings that influence later decisions
• outcome-backed evidence can seed, promote, demote, or retire reusable skills
• the runtime benchmark pack now shows the operator/runtime advantage with checked-in artifacts instead of relying only on prose
• personal-script/core runtime paths, protocol debt maintenance, and release doctoring are now strong enough that the live install path can be audited honestly before release

Client Capability Matrix

Capability	Claude Code	Codex	Claude Desktop
Shared brain / MCP runtime	Yes	Yes	Yes
Managed bootstrap document	~/.claude/CLAUDE.md	~/.codex/AGENTS.md	Not applicable
Global startup bootstrap sync	Native via hooks + bootstrap	Managed via bootstrap + Codex config initial_messages + mcp_servers.nexo	Managed MCP-only shared-brain metadata
nexo chat terminal client	Yes	Yes	No
Background automation backend	Recommended	Supported	No
Raw transcript source for Deep Sleep	Yes	Yes	No
Native hook depth	Deepest	Partial, compensated	None
Runtime doctor parity audit	Yes	Yes	Shared-brain only
Recommended today	Yes	Supported	Shared-brain companion

Supported Clients

Client	Status	Integration style	Notes
Claude Code	First-class	Managed install + hooks + bootstrap	Deepest NEXO parity today
Codex	First-class	Managed install + bootstrap + transcript parity	Best non-Claude terminal path
Claude Desktop	Companion	MCP-only shared brain	Useful as read/chat companion
Cursor	Documented companion	MCP + .cursor/rules	Good editor pairing; no Deep Sleep transcript parity yet
Windsurf	Documented companion	MCP + .windsurf/rules or repo AGENTS.md	Native MCP support, manual companion mode
Gemini CLI	Adapter included	MCP + GEMINI.md	Best when you want Gemini as a shared-brain companion, not the primary NEXO runtime

The Problem

AI coding agents are powerful but amnesic:

• No memory — closes a session, forgets everything
• Repeats mistakes — makes the same error you corrected yesterday
• No context — can't connect today's work with last week's decisions
• Reactive — waits for instructions instead of anticipating needs
• No learning — doesn't improve from experience
• No safety — stores anything it's told, including poisoned or redundant data

The Solution: A Cognitive Architecture

NEXO Brain implements the Atkinson-Shiffrin memory model from cognitive psychology (1968) — the same model that explains how human memory works:

What you say and do
    |
    +---> Sensory Register (raw capture, 48h)
    |       |
    |       +---> Attention filter: "Is this worth remembering?"
    |               |
    |               v
    +---> Short-Term Memory (7-day half-life)
    |       |
    |       +---> Used often? --> Consolidate to Long-Term Memory
    |       +---> Not accessed? --> Gradually forgotten
    |
    +---> Long-Term Memory (60-day half-life)
            |
            +---> Active: instantly searchable by meaning
            +---> Dormant: faded but recoverable ("oh right, I remember now!")
            +---> Near-duplicates auto-merged to prevent clutter

This isn't a metaphor. NEXO Brain literally implements Ebbinghaus forgetting curves, rehearsal-based reinforcement, and memory consolidation during automated "sleep" processes.

What Makes NEXO Brain Different

Without NEXO Brain	With NEXO Brain
Memory gone after each session	Persistent across sessions with natural decay and reinforcement
Repeats the same mistakes	Checks "have I made this mistake before?" before every action
Keyword search only	Finds memories by meaning, not just words
Starts cold every time	Resumes from the mental state of the last session
Same behavior regardless of context	Adapts tone and approach based on your mood
No relationship	Trust score that evolves — makes fewer redundant checks as alignment grows
Stores everything blindly	Prediction error gating rejects redundant information at write time
Vulnerable to memory poisoning	4-layer security pipeline scans every memory before storage
No proactive behavior	Context-triggered reminders fire when topics match, not just by date

How the Brain Works

Memory That Forgets (And That's a Feature)

NEXO Brain uses Ebbinghaus forgetting curves — memories naturally fade over time unless reinforced by use. This isn't a bug, it's how useful memory works:

• A lesson learned yesterday is strong. If you never encounter it again, it fades — because it probably wasn't important.
• A lesson accessed 5 times in 2 weeks gets promoted to long-term memory — because repeated use proves it matters.
• A dormant memory can be reactivated if something similar comes up — the "oh wait, I remember this" moment.

On top of that baseline, NEXO now keeps a lightweight per-memory profile:

• stability slows decay for memories that keep surviving retrieval and reinforcement
• difficulty speeds decay slightly for memories that tend to be weak, noisy, or harder to reuse correctly

That keeps the core Ebbinghaus model, but makes decay more individual and less purely global.

Semantic Search (Finding by Meaning)

NEXO Brain doesn't search by keywords. It searches by meaning using multilingual vector embeddings (fastembed, 384 dimensions).

Example: If you search for "deploy problems", NEXO Brain will find a memory about "SSH connection timeout on production server" — even though they share zero words. This is how human associative memory works.

Retrieval is now also smarter by default:

• HyDE auto mode expands conceptual or ambiguous queries when that improves recall
• Spreading activation auto mode adds a shallow associative boost for concept-heavy searches
• Exact lookup heuristics keep both off for literal file paths, IDs, stack traces, and other precision-sensitive queries

Metacognition (Thinking About Thinking)

Before every code change, NEXO Brain asks itself: "Have I made a mistake like this before?"

It searches its memory for related errors, warnings, and lessons learned. If it finds something relevant, it surfaces the warning BEFORE acting — not after you've already broken production.

Cognitive Dissonance

When you give an instruction that contradicts established knowledge, NEXO Brain doesn't silently obey or silently resist. It verbalizes the conflict:

"My memory says you prefer Tailwind over plain CSS, but you're asking me to write inline styles. Is this a permanent change or a one-time exception?"

You decide: paradigm shift (permanent change), exception (one-time), or override (old memory was wrong).

Sibling Memories

Some memories look identical but apply to different contexts. "How to deploy" for Project A is different from Project B. NEXO Brain detects discriminating entities (different OS, platform, language) and links them as siblings instead of merging them:

"Applying the Linux deploy procedure. Note: there's a sibling for macOS that uses a different port."

Trust Score (0-100)

NEXO Brain tracks alignment with you through a trust score:

• You say thanks --> score goes up --> reduces redundant verification checks
• Makes a mistake you already taught it --> score drops --> becomes more careful, checks more thoroughly
• The score doesn't control permissions — you're always in control. It's a mirror that helps calibrate rigor.

Sentiment Detection

NEXO Brain reads your tone (keywords, message length, urgency signals) and adapts:

• Frustrated? --> Ultra-concise mode. Zero explanations. Just solve the problem.
• In flow? --> Good moment to suggest that backlog item from last Tuesday.
• Urgent? --> Immediate action, no preamble.

Sleep Cycle

Like a human brain, NEXO Brain has automated processes that run while you're not using it:

Time	Process	Human Analogy
03:00	Decay + memory consolidation + merge duplicates + dreaming	Deep sleep consolidation
04:00	Clean expired data, prune redundant memories	Synaptic pruning
07:00	Self-audit, health checks, metrics	Waking up + orientation
23:30	Process day's events, extract patterns	Pre-sleep reflection
Boot	Catch-up: run anything missed while computer was off	--

If your Mac was asleep during any scheduled process, NEXO Brain catches up in order when it wakes.

Deep Sleep now also mixes recent context with older context across a 60-day horizon. Instead of only looking at the immediate past, it can surface:

• recurring multi-week themes
• cross-domain links between older learnings and current failures
• stale followups and topics that keep being mentioned but never formalized
• weighted project pressure based on diary activity, followups, learnings, and decision outcomes

It now also writes weekly and monthly Deep Sleep summaries so the overnight system can reuse higher-horizon signals instead of rediscovering everything from scratch every day.

Cognitive Cortex

The Cortex is a middleware cognitive layer that makes the agent think before acting. It implements architectural inhibitory control — the agent cannot bypass reasoning.

User message → Fast Path check → Simple chat? → Respond directly
                                → Action needed? → Cortex activates
                                                    ↓
                                              Generate cognitive state
                                              (goal, plan, unknowns, evidence)
                                                    ↓
                                              Middleware validates
                                              ├─ Unknowns? → ASK mode (tools blocked)
                                              ├─ No plan? → PROPOSE mode (read-only)
                                              └─ Plan + evidence → ACT mode (full access)

Feature	What It Does
Inhibitory Control	Physically restricts tools based on reasoning quality. Unknowns → can only ask. No plan → can only propose. Evidence + verification → can act.
Event-Driven Activation	Only activates on tool intent, ambiguity, destructive actions, or retries. Simple chat has zero overhead.
Trust-Gated Escalation	Low trust score → requires more evidence before allowing "act" mode. Trust builds through successful execution.
Core Rules Injection	Automatically surfaces relevant behavioral rules based on task type.
Activation Metrics	Tracks modes, inhibition rates, and task types for continuous improvement.

The Cortex was designed through a 3-way AI debate (Claude Opus 4.6 + GPT-5.4 + Gemini 3.1 Pro) and validated against 6 months of real production failures.

Durable Workflow Runtime

Memory and guardrails are not enough if long work still restarts from zero.

NEXO now ships a durable workflow runtime for multi-step and cross-session execution:

• nexo_workflow_open creates a persistent run with step metadata, idempotency key, priority, and shared state
• nexo_workflow_update records replayable checkpoints, retry metadata, approval gates, and the current actionable state
• nexo_workflow_resume tells the agent what to do next without guessing
• nexo_workflow_replay reconstructs the recent execution history honestly instead of pretending the run is still in memory
• nexo_workflow_list keeps active and blocked work visible so it does not disappear into reminders or prose notes

This is the bridge between "good memory" and "reliable execution": tasks can now preserve state, retries, approval gates, and next action across interruptions.

Context Continuity (Auto-Compaction)

NEXO Brain automatically preserves session context when Claude Code compacts conversations. Using PreCompact and PostCompact hooks:

• PreCompact: Saves a complete session checkpoint to SQLite (task, files, decisions, errors, reasoning thread, next step)
• PostCompact: Re-injects a structured Core Memory Block into the conversation, so the session continues seamlessly

This means long sessions (8+ hours) feel like one continuous conversation instead of restarting after each compaction.

How it works:

1. Configure the hooks in your Claude Code settings.json
2. NEXO Brain's heartbeat automatically maintains the checkpoint
3. When compaction happens, the PreCompact hook reads the checkpoint and injects a recovery block
4. The session continues from exactly where it left off

Setup:

{
  "hooks": {
    "PreCompact": [{
      "matcher": "*",
      "hooks": [{"type": "command", "command": "bash $NEXO_HOME/hooks/pre-compact.sh", "timeout": 10}]
    }],
    "PostCompact": [{
      "matcher": "*",
      "hooks": [{"type": "command", "command": "bash $NEXO_HOME/hooks/post-compact.sh", "timeout": 10}]
    }]
  }
}

2 new MCP tools: nexo_checkpoint_save (manual or hook-triggered checkpoint), nexo_checkpoint_read (retrieves the latest checkpoint for context injection).

Cognitive Features

NEXO Brain provides 150+ MCP tools across 23 categories. These features implement cognitive science concepts that go beyond basic memory:

Input Pipeline

Feature	What It Does
Prediction Error Gating	Only novel information is stored. Redundant content that matches existing memories is rejected at write time, keeping your memory clean without manual curation.
Security Pipeline	4-layer defense against memory poisoning: injection detection, encoding analysis, behavioral anomaly scoring, and credential scanning. Every memory passes through all four layers before storage.
Quarantine Queue	New facts enter quarantine status and must pass a promotion policy before becoming trusted knowledge. Prevents unverified information from influencing decisions. Automated nightly processing promotes, rejects, or expires items.
Secret Redaction	Auto-detects and redacts API keys, tokens, passwords, and other sensitive data before storage. Secrets never reach the vector database.

Memory Management

Feature	What It Does
Pin / Snooze / Archive	Granular lifecycle states for memories. Pin = never decays (critical knowledge). Snooze = temporarily hidden (revisit later). Archive = cold storage (searchable but inactive).
Intelligent Chunking	Adaptive chunking that respects sentence and paragraph boundaries. Produces semantically coherent chunks instead of arbitrary token splits, reducing retrieval noise.
Adaptive Decay	Decay rate still follows Ebbinghaus as the base model, but now also adapts per memory using stability and difficulty profiles. Frequently reinforced memories become stickier; fragile memories fade sooner.
Auto-Migration	Formal schema migration system (schema_migrations table) tracks all database changes. Safe, reversible schema evolution for production systems — upgrades never lose data.
Auto-Merge Duplicates	Batch cosine deduplication during the 03:00 sleep cycle. Respects sibling discrimination — similar memories about different contexts are kept separate.
Memory Dreaming	Discovers hidden connections between recent memories during the 03:00 sleep cycle and now feeds a 60-day long-horizon Deep Sleep blend, so older patterns can reappear when they become relevant again.

Operational Continuity

Feature	What It Does
Hot Context 24h	Keeps active topics, blockers, and waiting states fresh across sessions, clients, cron ticks, and channel changes. This is the shared recent-memory substrate for operational continuity.
Pre-Action Context Bundle	Loads recent contexts, recent events, related reminders, and related followups before acting, so continuity is explicit instead of prompt-only.
Transcript Fallback	When recent-memory capture is thin or missing, NEXO can now search and read recent Claude Code / Codex transcripts directly through MCP instead of pretending the conversation is lost.
Live System Catalog	NEXO can now inspect its own current surface — core tools, plugin tools, skills, scripts, crons, projects, and artifacts — through a live catalog derived from canonical sources at read time.

Retrieval

Feature	What It Does
HyDE Query Expansion	Generates hypothetical answer embeddings for richer semantic search. NEXO now auto-enables HyDE for conceptual or ambiguous queries while keeping literal lookups conservative.
Hybrid Search (FTS5+BM25+RRF)	Combines dense vector search with BM25 keyword search via Reciprocal Rank Fusion. Outperforms pure semantic search on precise terminology and code identifiers.
Cross-Encoder Reranking	After initial vector retrieval, a cross-encoder model rescores candidates for precision. The top-k results are reordered by true semantic relevance before being returned to the agent.
Multi-Query Decomposition	Complex questions are automatically split into sub-queries. Each component is retrieved independently, then fused for a higher-quality answer — improves recall on multi-faceted prompts.
Temporal Indexing	Memories are indexed by time in addition to semantics. Time-sensitive queries ("what did we decide last Tuesday?") use temporal proximity scoring alongside semantic similarity.
Spreading Activation	Graph-based co-activation network. NEXO now auto-enables a shallow spreading pass for concept-heavy queries, improving contextual recall without turning every exact lookup into a fuzzy search.
Recall Explanations	Transparent score breakdown for every retrieval result. Shows exactly why a memory was returned: semantic similarity, recency, access frequency, and co-activation bonuses.

Proactive

Feature	What It Does
Prospective Memory	Context-triggered reminders that fire when conversation topics match, not just by date. "Remind me about X when we discuss Y" works naturally.
Hook Auto-capture	Extracts decisions, corrections, and factual statements from conversations automatically. You don't need to explicitly say "remember this" — the system detects what's worth storing.
Session Summaries	Automatic end-of-session summarization that distills key decisions, errors, and follow-ups into a compact diary entry. The next session starts with full context — not a cold slate.
Smart Startup	Pre-loads relevant cognitive memories at session boot by composing a query from pending followups, due reminders, and last session's topics. Every session starts with the right context — not a cold search.
Context Packets	Bundles all area knowledge (learnings, recent changes, active followups, preferences, cognitive memories) into a single injectable packet for subagent delegation. Subagents never start blind again.
Auto-Prime by Topic	Heartbeat detects project/area keywords in conversation and automatically surfaces the most relevant learnings. No explicit memory query needed — context arrives proactively.

Benchmark: LoCoMo (ACL 2024)

NEXO Brain was evaluated on LoCoMo (ACL 2024), a long-term conversation memory benchmark with 1,986 questions across 10 multi-session conversations.

System	F1	Adversarial	Hardware
NEXO Brain v0.5.0	0.588	93.3%	CPU only
GPT-4 (128K full context)	0.379	—	GPU cloud
Gemini Pro 1.0	0.313	—	GPU cloud
LLaMA-3 70B	0.295	—	A100 GPU
GPT-3.5 + Contriever RAG	0.283	—	GPU

+55% vs GPT-4. Running entirely on CPU.

Key findings:

• Outperforms GPT-4 (128K full context) by 55% on F1 score
• 93.3% adversarial rejection rate — reliably says "I don't know" when information isn't available
• 74.9% recall across 1,986 questions
• Open-domain F1: 0.637 | Multi-hop F1: 0.333 | Temporal F1: 0.326
• Runs on CPU with local multilingual embeddings — no GPU required
• First MCP memory server benchmarked on a peer-reviewed dataset

Full results in benchmarks/locomo/results/.

Nervous System (v2.0.0)

NEXO Brain doesn't just respond — it runs 13 core recovery-aware background jobs plus optional helpers, like a biological nervous system. They handle maintenance, health monitoring, and self-improvement without any user interaction:

Script	Schedule	What It Does
cognitive-decay	03:00 daily	Ebbinghaus decay + memory consolidation + duplicate merging + dreaming
sleep	04:00 daily	Synaptic pruning, expired data cleanup
deep-sleep	04:30 daily	4-phase overnight pipeline: Collect→Extract→Synthesize→Apply. Analyzes all sessions, detects emotional patterns, abandoned projects, productivity issues, and auto-creates learnings
self-audit	07:00 daily	Health checks, guard stats, trust score review, metrics
postmortem	23:30 daily	Session consolidation, extract patterns from day's events
catchup	On boot	Runs any missed scheduled processes (Mac was off/asleep)
tcc-approve	On boot (macOS)	Auto-approve macOS permissions for Claude Code updates
prevent-sleep	Always (daemon)	Keeps machine awake for nocturnal processes (caffeinate/systemd-inhibit)
evolution	Weekly (Sun)	Self-improvement proposals — NEXO suggests and applies enhancements
followup-hygiene	Weekly (Sun)	Normalizes statuses, flags stale followups, cleans orphans
learning-housekeep	03:15 daily	Dedup learnings, adjust weights by usage, process overdue reviews, reconcile decision outcomes
immune	Every 30 min	Quarantine processing, memory promotion/rejection, synaptic pruning
impact-scorer	05:45 daily	Scores active followups so queues can prioritize by expected impact
synthesis	06:00 daily	Memory synthesis — discovers cross-memory patterns
outcome-checker	08:00 daily	Verifies tracked outcomes and marks them met, pending, or missed
watchdog	Every 30 min	Monitors services, LaunchAgents, and infrastructure health
auto-close-sessions	Every 5 min	Cleans stale sessions

Core processes are defined in src/crons/manifest.json and auto-synced to your system by nexo_update. On macOS they run via LaunchAgents; on Linux via systemd user timers. tcc-approve, prevent-sleep, and backup are platform/personal helpers — not in the manifest but listed above for completeness. Personal crons (your own scripts) are never touched by the sync. If your Mac was asleep during a scheduled process, the catch-up script re-runs everything in order when it wakes.

Deep Sleep v2 — Overnight Learning (v2.1.0)

Deep Sleep is a 4-phase pipeline that runs at 4:30 AM and makes NEXO smarter while you sleep:

Phase 1: COLLECT (Python)
├── Reads all session transcripts from the day
├── Splits each session into individual .txt files
└── Gathers DB state (followups, learnings, trust)

Phase 2: EXTRACT (Opus, one call per session)
├── 8 types of findings per session:
│   ├── Uncaptured corrections (user corrected agent, no learning saved)
│   ├── Self-corrected errors (knowledge gaps to fix)
│   ├── Unformalised ideas (mentioned but never tracked)
│   ├── Missed commitments (promised but no followup)
│   ├── Protocol violations (guard_check, heartbeat, change_log)
│   ├── Emotional signals (frustration, flow, satisfaction)
│   ├── Abandoned projects (started but not finished)
│   └── Productivity patterns (corrections, proactivity, tool efficiency)
└── Outputs per-session JSON with findings + emotional timeline

Phase 3: SYNTHESIZE (Opus, one call)
├── Cross-session patterns (same error in 5 sessions = systemic)
├── Daily mood arc with score (0.0 = terrible day, 1.0 = great day)
├── Recurring triggers (what causes frustration vs flow)
├── Productivity analysis (corrections, tool efficiency)
├── Abandoned project detection
├── Morning agenda (prioritized)
└── Calibration recommendations

Phase 4: APPLY (Python)
├── Auto-creates learnings from high-confidence findings
├── Creates followups for unfinished work
├── Updates mood_history in calibration.json (30-day rolling)
├── Generates session-tone.json (emotional guidance for next session)
└── Writes morning-briefing.md

Session Tone — Emotional Intelligence

Deep Sleep generates a session-tone.json that tells NEXO how to behave next morning:

• Agent made many mistakes yesterday → Acknowledge them, show what was learned, demonstrate improvement
• User had a bad day (mood < 40%) → Supportive approach, lighter start, avoid known frustration triggers
• User had a great day (mood > 70%) → Reinforce momentum, reference wins, push ambitious goals
• Agent was too reactive → Be proactive today, don't wait for instructions

This is read by nexo_smart_startup and injected into every session's context. NEXO adapts its personality based on real behavioral data, not just configuration.

Cron Manifest & Scheduler (v2.4.0)

All core crons are defined in src/crons/manifest.json. When you run nexo_update, the sync script:

• Installs new crons from the manifest
• Updates changed schedules/intervals
• Removes crons no longer in the manifest (only core ones)
• Never touches personal crons you created yourself

Every cron execution is tracked in the cron_runs table via a universal wrapper. Use nexo_schedule_status to see what ran overnight:

✅ deep-sleep: 1/1 OK, 4523s avg — 37 sessions, 259 findings
✅ immune: 48/48 OK, 2s avg
❌ evolution: 0/1 OK — CLI timeout

Add personal crons from conversation with nexo_schedule_add — generates LaunchAgent (macOS) or systemd timer (Linux) automatically.

Skill Auto-Creation (v2.4.0)

Deep Sleep automatically extracts reusable procedures from successful multi-step tasks and stores them as skills with full procedural content (steps, gotchas, markdown).

Pipeline: trace → draft → published → archived. Trust rises with successful use, decays without it. No human approval gates.

7 MCP tools: nexo_skill_create, nexo_skill_match, nexo_skill_get, nexo_skill_result, nexo_skill_list, nexo_skill_merge, nexo_skill_stats.

Dashboard (v1.6.0)

A web interface at localhost:6174 with 6 interactive pages for visual insight into your brain's state:

Page	What It Shows
Overview	System health at a glance — memory counts, trust score, active sessions, recent changes
Graph	Interactive D3.js visualization of the knowledge graph (nodes, edges, clusters)
Memory	Browse and search all memory stores (STM, LTM, sensory, archived)
Somatic	Pain map per file/area — see which parts of your codebase cause the most errors
Adaptive	Personality signals, learned weights, and current mode
Sessions	Active and historical sessions with timeline and diary entries

Built with FastAPI backend and D3.js frontend. Dashboard files are installed to NEXO_HOME/dashboard/ but must be started manually:

python3 ~/.nexo/dashboard/app.py

This opens localhost:6174 in your browser. Add --port 8080 to change the port or --no-browser to skip auto-opening.

Full Orchestration System

Memory alone doesn't make a co-operator. What makes the difference is the behavioral loop — the automated discipline that ensures every session starts informed, runs with guardrails, and ends with self-reflection.

Automated Hooks

7 hooks fire automatically at key moments in every Claude Code session:

Hook	When	What It Does
SessionStart (timestamp)	Session opens	Writes session timestamp for staleness detection
SessionStart (briefing)	Session opens	Generates briefing from SQLite: overdue reminders, today's tasks, pending followups, active sessions. Cleans up post-mortem flags.
Stop	Session ends	Mandatory post-mortem: self-critique (5 questions), session buffer entry, followup creation, proactive seeds for next session
PostToolUse (capture)	After each tool call	Captures meaningful mutations to the Sensory Register + auto-diary every 10 tool calls
PostToolUse (inbox)	After each tool call	Inter-terminal inbox delivery between parallel sessions
PreCompact	Before context compression	Saves full session checkpoint to SQLite — task, files, decisions, errors, reasoning thread + emergency diary
PostCompact	After context compression	Re-injects Core Memory Block so the session continues seamlessly from where it left off

The Session Lifecycle

Session starts
    ↓
SessionStart hook generates briefing
    ↓
Operator reads diary, reminders, followups
    ↓
Heartbeat on every interaction (sentiment, context shifts)
    ↓
Guard check before every code edit
    ↓
PreCompact hook saves full checkpoint if conversation is compressed
    ↓
PostCompact hook re-injects Core Memory Block → session continues seamlessly
    ↓
Stop hook refreshes the diary draft and approves immediately:
  - Latest changes and decisions stay attached to the active session
  - Session buffer keeps structured tool activity for downstream processing
  - Followups and closing synthesis happen inline when the agent detects real closing intent
  - No mid-conversation blocking from the hook itself
    ↓
Nocturnal post-mortem consolidator processes the buffer mechanically
    ↓
Nocturnal processes: decay, consolidation, self-audit, dreaming

Reflection Engine

NEXO still ships nexo-reflection.py as a standalone analyzer for session_buffer.jsonl. It is not currently auto-triggered by the stop hook:

• Extracts recurring tasks, error patterns, mood trends
• Updates user_model.json with observed behavior
• No LLM required — runs as pure Python

Auto-Migration

Existing users upgrading from any previous version:

npx nexo-brain  # detects current version, migrates automatically

• Updates hooks, core files, plugins, scripts, and LaunchAgent templates
• Runs database schema migrations automatically
• Never touches your data (memories, learnings, preferences)
• Saves updated CLAUDE.md as reference (doesn't overwrite customizations)

Runtime CLI (v2.6.0)

NEXO Brain includes a local CLI that runs independently of any single terminal client:

• nexo chat — launch a NEXO terminal client; if both Claude Code and Codex are available, it asks every time which one to open and puts the last-used client first
• nexo update — sync runtime from source, run migrations, reconcile schedules
• nexo doctor --tier runtime — boot/runtime/deep diagnostics with --fix mode
• nexo scripts list — list all personal scripts and their status
• nexo scripts reconcile — align declared schedules with actual LaunchAgents/systemd
• nexo -v — show installed runtime version

The CLI lives at NEXO_HOME/bin/nexo and is added to your PATH during install.

Personal Scripts Registry (v2.6.0)

Scripts in NEXO_HOME/scripts/ are first-class managed entities:

• Tracked in SQLite with metadata, categories, and schedule associations
• Inline metadata in scripts declares name, runtime, schedule, and recovery policy
• nexo scripts create NAME scaffolds a new script with the correct template
• nexo scripts reconcile creates/repairs LaunchAgents from declared metadata
• nexo scripts sync discovers filesystem state and updates the registry
• nexo doctor --tier runtime detects orphaned schedules, missing plists, and drift

Personal scripts are completely separate from core NEXO processes. The crons/manifest.json defines core; everything in NEXO_HOME/scripts/ is personal.

If you need to decide between a personal script, skill, plugin, or schedule, use docs/personal-artifacts-manual.md. That is the canonical operational guide.

Recovery-Aware Background Jobs (v2.6.2)

Core and personal jobs now declare explicit recovery contracts in crons/manifest.json:

Field	Purpose
recovery_policy	catchup, restart, restart_daemon, or skip
run_on_boot	Re-run when the machine starts
run_on_wake	Re-run after sleep/resume
idempotent	Safe to re-run without side effects
max_catchup_age	Maximum age of a missed window to still catch up

If the Mac was asleep during a scheduled window, catchup detects the gap from cron_runs (not a state file) and re-executes eligible jobs once. Interval-based personal scripts get a single recovery run, not repeated ticks.

For personal daemon-style helpers, recovery_policy=restart_daemon plus schedule_required=true declares an official KeepAlive schedule. NEXO can now reconcile and repair those daemons instead of treating them as unmanaged legacy LaunchAgents.

Startup Preflight (v2.6.2)

Before nexo chat or MCP server start, NEXO runs a preflight check:

1. Apply power policy (caffeinate on macOS, systemd-inhibit on Linux)
2. Run safe local migrations and backfills
3. Sync personal scripts registry
4. For dev-linked runtimes: check if source repo is behind, pull if safe, sync to runtime

This replaces the old "blind startup" where NEXO entered without verifying runtime health.

Knowledge Graph (v0.8)

A bi-temporal entity-relationship graph with 988 nodes and 896 edges. Entities and relationships carry both valid-time (when the fact was true) and system-time (when it was recorded), enabling temporal queries like "what did we know about X last Tuesday?". BFS traversal discovers multi-hop connections between concepts. Event-sourced edges with smart dedup (ADD/UPDATE/NOOP) prevent redundant writes while preserving full history.

4 MCP tools: nexo_kg_query (SPARQL-like queries), nexo_kg_path (shortest path between entities), nexo_kg_neighbors (direct connections), nexo_kg_stats (graph metrics).

Cross-Platform Support

Full Linux support and Windows via WSL. The installer detects the platform and configures the appropriate process manager (LaunchAgents on macOS, catch-up on startup for Linux). PEP 668 compliance (venv on Ubuntu 24.04+). Session keepalive prevents phantom sessions during long tasks. Opportunistic maintenance runs cognitive processes when resources are available.

Windows users: NEXO Brain requires WSL (Windows Subsystem for Linux). Install WSL first, then run npx nexo-brain inside the Ubuntu/WSL terminal.

Storage Router

A new abstraction layer routes storage operations through a unified interface, making the system multi-tenant ready. Each operator's data is isolated while sharing the same cognitive engine.

Learned Weights & Somatic Markers (v0.7.0)

Adaptive Learned Weights

Signal weights learn from real user feedback via Ridge regression. A 2-week shadow mode observes before activating. Weight momentum (85/15 blend) prevents personality whiplash. Automatic rollback if correction rate doubles.

Somatic Markers (Pain Memory)

Files and areas that cause repeated errors accumulate a risk score (0.0–1.0). The guard system warns on HIGH RISK (>0.5) and CRITICAL RISK (>0.8), lowering thresholds for more paranoid checking. Clean guard checks reduce risk multiplicatively (×0.7). Nightly decay (×0.95) ensures old pain fades.

Adaptive Personality v2

6 weighted signals: vibe, corrections, brevity, topic, tool errors, git diff. Emergency keywords bypass hysteresis. Severity-weighted decay. Manual override via nexo_adaptive_override.

Quick Start

Claude Code (Primary)

npx nexo-brain

The installer handles everything and syncs the same nexo MCP brain into Claude Code, Claude Desktop, and Codex when those clients are present:

  How should I call myself? (default: Nova) > Atlas

  Can I explore your workspace to learn about your projects? (y/n) > y

  Keep Mac awake so my cognitive processes run on schedule? (y/n) > y

  Installing cognitive engine dependencies...
  Setting up NEXO home...
  Scanning workspace...
    - 3 git repositories
    - Node.js project detected
  Configuring MCP server...
  Setting up nervous system...
    15 core recovery-aware jobs configured.
    Dashboard configured at localhost:6174.
  Caffeinate enabled.
  Generating operator instructions...

  +----------------------------------------------------------+
  |  Atlas is ready. Type 'atlas' to start.                  |
  +----------------------------------------------------------+

Docker Compose

NEXO now ships a root-level docker-compose.yml for a persistent containerized runtime. It does two things at once:

• keeps NEXO_HOME on a named volume
• exposes a remote MCP endpoint at http://localhost:8000/mcp for IDEs that support HTTP/SSE MCP

Start it with:

docker compose up -d

For Claude Code and Codex, keep using stdio and point the MCP command at the running container:

docker compose exec -T nexo python src/server.py

That gives you the same persistent brain in the container while keeping terminal clients on their native stdio transport. The full step-by-step flow, health checks, and config examples live in docs/docker-setup.md.

Starting a Session

After install, use the runtime CLI:

nexo chat          # Launch a NEXO terminal client (asks if both Claude Code and Codex are available)
nexo doctor        # Check runtime health
nexo update        # Pull latest version and sync
nexo clients sync  # Re-sync Claude Code/Desktop/Codex to the same brain
nexo scripts list  # See your personal scripts

During install, NEXO now asks which interactive clients you want to connect, which one nexo chat should suggest first when multiple terminal clients are available, whether to enable background automation, which backend should run that automation, and which model profile each active terminal/backend should use. Shared brain stays on in every mode.

Public entry points for the mental model now stay intentionally small:

• nexo_remember
• nexo_memory_recall
• nexo_consolidate
• nexo_run_workflow
• nexo_pre_action_context
• nexo_transcript_search
• nexo_system_catalog

If you want the shell or Python wrappers instead of raw MCP tools:

• docs/quickstart-5-minutes.md
• docs/memory-classes.md
• docs/recent-memory-fallbacks-and-system-catalog.md
• docs/sdk-python.md
• docs/reference-verticals.md
• compare/README.md

The model you pick during install is used everywhere — interactive sessions, automation scripts, and all task profiles. Change it once in your preferences and every part of the system follows. Default: Opus 4.7 with 1M context.

Or use the shell alias created during install (e.g. atlas), which now runs nexo chat . so it opens the terminal client you pick for that session, with the last-used option shown first.

Your operator will greet you immediately — adapted to the time of day, resuming from where you left off. No cold starts.

Contributing

NEXO is being hardened in public, and the best contributions now are not only code changes but also real workflow feedback:

• Open issues when a client flow feels asymmetric across Claude Code, Codex, Claude Desktop, OpenClaw, or other MCP environments.
• Send PRs for docs, install UX, tests, compatibility checks, and public-facing copy.
• If you use NEXO in production-like daily work, include exact runtime symptoms and commands in bug reports. This project improves fastest when the operational reality is concrete.

The project still recommends Claude Code as the primary path, but contributions that improve Codex, client parity, installer clarity, and ecosystem integrations are especially valuable.

Maintainers and contributors touching startup, bootstrap, Deep Sleep, or shared-brain behavior should also use the client parity checklist:

• docs/client-parity-checklist.md
• python3 scripts/verify_release_readiness.py

What Gets Installed

Component	What	Where
Cognitive engine	Python: fastembed, numpy, vector search	pip packages
MCP server	150+ tools for memory, cognition, learning, guard	NEXO_HOME/
Claude Code Plugin	Marketplace-ready (packaging verified)	.claude-plugin/
Plugins	Guard, episodic memory, cognitive memory, entities, preferences, update, etc.	Code: src/plugins/, Personal: NEXO_HOME/plugins/
Hooks (7)	SessionStart, Stop, PostToolUse, PreCompact, PostCompact	NEXO_HOME/hooks/
Nervous system	13 core recovery-aware jobs + optional helpers (dashboard, prevent-sleep)	NEXO_HOME/scripts/
Dashboard	Web UI at localhost:6174 (23 modules, dark theme) — opt-in, always-on	NEXO_HOME/dashboard/
Runtime CLI	nexo command: scripts, doctor, skills, update	NEXO_HOME/bin/
Doctor	Unified diagnostics: boot/runtime/deep tiers, --fix mode	src/doctor/
Skills v2	Executable skills with guide/execute/hybrid modes, approval levels	NEXO_HOME/skills/
Startup Preflight	Health checks before every nexo chat or server start	Built into CLI
CLAUDE.md	Complete operator instructions (Codex, hooks, guard, trust, memory)	~/.claude/CLAUDE.md
Schedule config	schedule.json with customizable process times and timezone	NEXO_HOME/config/
Auto-update	Non-blocking startup check (5s max), opt-out via schedule.json	Built into server startup
CLAUDE.md tracker	Version-tracked core sections with safe updates preserving customizations	Built into auto-update
Shared client sync	Same nexo MCP entry wired into Claude Code, Claude Desktop, and Codex	User config dirs
Client/backend preferences	Selected interactive clients, default terminal client, automation backend, and model/reasoning profiles per client	NEXO_HOME/config/schedule.json
Auto-diary	3-layer system: PostToolUse every 10 calls, PreCompact emergency, heartbeat DIARY_OVERDUE	Built into hooks
Claude Code config	MCP server + 7 hooks + 15 managed processes registered	~/.claude/settings.json

Runtime CLI

After installation or auto-update, NEXO adds NEXO_HOME/bin to your shell PATH. Open a new terminal and the nexo command provides operational tools:

# Personal Scripts
nexo scripts list              # List your personal scripts
nexo scripts run my-script     # Run a script with injected NEXO env
nexo scripts doctor            # Validate all personal scripts
nexo scripts call nexo_learning_search --input '{"query":"cron"}' # Call any MCP tool

# Skills v2
nexo skills sync               # Sync filesystem skill definitions into SQLite
nexo skills list               # List published/stable skills
nexo skills get SK-...         # Inspect a skill definition
nexo skills apply SK-... --dry-run --json  # Resolve guide/execute/hybrid without running it
nexo skills approve SK-... --execution-level local --approved-by Francisco  # Optional metadata override
nexo skills evolution          # Show text→script and improvement candidates

# Unified Doctor
nexo doctor                    # Quick boot diagnostics
nexo doctor --tier all         # Full system check (boot + runtime + deep)
nexo doctor --tier runtime --json  # Machine-readable health report
nexo doctor --fix              # Apply deterministic repairs

Personal scripts live in NEXO_HOME/scripts/ with inline metadata. Their Python templates now include run_automation_text(...), which routes work through the configured NEXO automation backend instead of hardcoding claude -p or provider-specific model names. nexo-agent-run.py now also supports task profiles (fast, balanced, deep) plus safe backend fallback, so automations can prefer cheaper/faster Codex paths or deeper Claude paths without hardcoding one provider forever. See docs/writing-scripts.md for details and docs/personal-artifacts-manual.md for the canonical artifact decision guide.

Skills v2 combine procedural guides with optional executable scripts. Personal skills live in NEXO_HOME/skills/, packaged core skills live in NEXO_CODE/skills/ during development and NEXO_HOME/skills-core/ in installed environments, and staged runtime copies live in NEXO_HOME/skills-runtime/. Execution is fully autonomous: Deep Sleep can evolve mature guide skills into executable drafts automatically, and runtime execution no longer waits for manual approval. See docs/skills-v2.md for the full model and docs/personal-artifacts-manual.md for the boundary between skills, scripts, plugins, and schedules.

The Doctor system reads existing health artifacts (immune, watchdog, self-audit) without triggering repairs in default mode.

Requirements

• macOS or Linux (Windows via WSL)
• Node.js 18+ (for the installer)
• Claude Code is the primary recommended client. It remains the most mature NEXO path: native hooks, the most battle-tested automation contract, and the clearest parity with historical production behavior.
• Model: You pick your model during install and every component uses it. Default is Opus 4.7 with 1M context. Scripts and automation profiles read from a single preference — no hardcoded model strings.
• Python 3, Homebrew, and the selected required client/backend can be installed automatically when NEXO has a supported installer path for that dependency.

Architecture

Unified Code/Data Separation (v2.0.0)

NEXO Brain separates code (immutable, in the repo or npm package) from data (personal, in NEXO_HOME):

Path	Contents
src/ (or npm package)	Server, plugins, hooks, scripts — never modified at runtime
NEXO_HOME/ (default ~/.nexo/)	Database, config, personal plugins, schedule, backups
NEXO_HOME/config/schedule.json	Customizable process schedules, timezone, auto_update flag
NEXO_HOME/plugins/	Personal plugins that override or extend repo plugins
NEXO_HOME/data/	SQLite databases (nexo.db, cognitive.db), migration state

The plugin loader scans src/plugins/ first (base), then NEXO_HOME/plugins/ (personal override by filename). This dual-directory approach lets you extend NEXO without forking the repo. The client sync layer points Claude Code, Claude Desktop, and Codex at the same runtime and NEXO_HOME, so all three clients share one brain instead of drifting into separate local memories.

150+ MCP Tools across 23 Categories

Category	Count	Tools	Purpose
Cognitive	8	retrieve, stats, inspect, metrics, dissonance, resolve, sentiment, trust	The brain — memory, RAG, trust, mood
Cognitive Input	5	prediction_gate, security_scan, quarantine, promote, redact	Input pipeline — gating, security, quarantine
Cognitive Advanced	8	hyde_search, spread_activate, explain_recall, dream, prospect, hook_capture, pin, archive	Advanced retrieval, proactive, lifecycle
Guard	3	check, stats, log_repetition	Metacognitive error prevention
Episodic	10	change_log/search/commit, decision_log/outcome/search, review_queue, diary_write/read, recall	What happened and why
Sessions	4	startup, heartbeat, stop, status	Session lifecycle + context shift detection + inter-terminal auto-inbox
Coordination	7	track, untrack, files, send, ask, answer, check_answer	Multi-session file coordination + messaging
Reminders	5	list, create, update, complete, delete	User's tasks and deadlines
Followups	4	create, update, complete, delete	System's autonomous verification tasks
Learnings	5	add, search, update, delete, list	Error patterns and prevention rules
Credentials	5	create, get, update, delete, list	Local credential storage (plaintext SQLite — protect with filesystem permissions)
Task History	3	log, list, frequency	Execution tracking and overdue alerts
Menu	1	menu	Operations center with box-drawing UI
Entities	5	search, create, update, delete, list	People, services, URLs
Preferences	4	get, set, list, delete	Observed user preferences
Agents	5	get, create, update, delete, list	Agent delegation registry
Backup	3	now, list, restore	SQLite data safety
Evolution	5	propose, approve, reject, status, history	Self-improvement proposals
Adaptive & Somatic	4	adaptive_weights, adaptive_override, somatic_check, somatic_stats	Learned signal weights + pain memory per file
Knowledge Graph	4	kg_query, kg_path, kg_neighbors, kg_stats	Bi-temporal entity-relationship graph
Context Continuity	2	checkpoint_save, checkpoint_read	Auto-compaction session preservation
Personal Scripts	9	sync, list, create, remove, schedules, unschedule, reconcile, classify, ensure_schedules	Script lifecycle management
Skills	12	match, create, get, list, apply, approve, result, stats, evolution_candidates, merge, sync, featured	Reusable procedure library
Schedule	2	add, status	Personal cron scheduling
Doctor	1	doctor	Runtime diagnostics with --fix
Update	1	update	Pull latest code, backup, migrate, verify (with rollback)

Plugin System

NEXO Brain supports hot-loadable plugins with a dual-directory loader. Base plugins live in src/plugins/ (repo). Personal plugins go in NEXO_HOME/plugins/ and can override base plugins by filename. Drop a .py file in NEXO_HOME/plugins/:

# my_plugin.py
def handle_my_tool(query: str) -> str:
    """My custom tool description."""
    return f"Result for {query}"

TOOLS = [
    (handle_my_tool, "nexo_my_tool", "Short description"),
]

Reload without restarting: nexo_plugin_load("my_plugin.py")

Use a personal plugin only when you need a new MCP tool in the runtime surface. If the real need is autonomous execution or scheduling, use a personal script plus managed schedule instead. The canonical decision guide is docs/personal-artifacts-manual.md.

Data Privacy

• Everything stays local. All data in ~/.nexo/, never uploaded anywhere.
• No telemetry. No analytics. No phone-home.
• No cloud dependencies. Vector search runs on CPU (fastembed), not an API.
• Auto-update is resilient. NEXO checks for updates on startup. If an update fails, it continues with the current version and notifies you. Local migrations (database schema, configuration) always run. Network updates (git pull) can be disabled by setting auto_update: false in NEXO_HOME/config/schedule.json.
• Secret redaction. API keys and tokens are stripped before they ever reach memory storage.

The Psychology Behind NEXO Brain

NEXO Brain isn't just engineering — it's applied cognitive psychology:

Psychological Concept	How NEXO Brain Implements It
Atkinson-Shiffrin (1968)	Three memory stores: sensory register --> STM --> LTM
Ebbinghaus Forgetting Curve (1885)	Exponential decay: strength = strength * e^(-lambda * time)
Rehearsal Effect	Accessing a memory resets its strength to 1.0
Memory Consolidation	Nightly process promotes frequently-used STM to LTM
Prediction Error	Only surprising (novel) information gets stored — redundant input is gated
Spreading Activation (Collins & Loftus, 1975)	Retrieving a memory co-activates related memories through an associative graph
HyDE (Gao et al., 2022)	Hypothetical document embeddings improve semantic recall
Prospective Memory (Einstein & McDaniel, 1990)	Context-triggered intentions fire when cue conditions match
Metacognition	Guard system checks past errors before acting
Cognitive Dissonance (Festinger, 1957)	Detects and verbalizes conflicts between old and new knowledge
Theory of Mind	Models user behavior, preferences, and mood
Synaptic Pruning	Automated cleanup of weak, unused memories
Associative Memory	Semantic search finds related concepts, not just matching words
Memory Reconsolidation	Dreaming process discovers hidden connections during sleep

Integrations

Claude Code (Primary)

NEXO Brain is designed as an MCP server. Claude Code remains the primary recommended client and the most complete integration path:

npx nexo-brain

All 150+ tools are available immediately after installation. The installer configures Claude Code's ~/.claude/settings.json automatically. The recommended Claude profile is Opus 4.7 with 1M context.

Claude Desktop

When Claude Desktop is installed, nexo-brain, nexo update, and nexo clients sync keep claude_desktop_config.json pointed at the same local NEXO runtime and NEXO_HOME.

Codex

When Codex CLI is available, nexo-brain, nexo update, and nexo clients sync register the same nexo MCP server via codex mcp add, so Codex uses the same local memory store as Claude Code and Claude Desktop. If selected during install, nexo chat can open Codex directly and background automation can also run through Codex. Interactive nexo chat launches use Codex's aggressive no-confirmation mode so the session does not stall on repetitive approval prompts. Codex uses the same model you configured during install — no separate model override is needed. Runtime Doctor also audits recent Codex sessions for NEXO startup markers and conditioned-file protocol discipline so parity drift does not hide behind the lack of native Claude-style hooks.

Cursor

Cursor works well as a documented companion client. Point Cursor at the same local nexo MCP server and add a project rule that forces nexo_startup, nexo_heartbeat, and the protocol path on real work. See docs/integrations/cursor.md.

Windsurf

Windsurf/Cascade supports MCP plus durable repo rules. Use the same local nexo server and add NEXO startup/protocol instructions in .windsurf/rules/ or your repo AGENTS.md. See docs/integrations/windsurf.md.

Gemini CLI

Gemini CLI can share the same local NEXO brain through mcpServers in ~/.gemini/settings.json plus a repo GEMINI.md. NEXO now ships a starter adapter in adapters/gemini/README.md.

OpenClaw

NEXO Brain also works as a cognitive memory backend for OpenClaw:

MCP Bridge (Zero Code)

Add NEXO Brain to your OpenClaw config at ~/.openclaw/openclaw.json:

{
  "mcp": {
    "servers": {
      "nexo-brain": {
        "command": "python3",
        "args": ["~/.nexo/server.py"],
        "env": {
          "NEXO_HOME": "~/.nexo"
        }
      }
    }
  }
}

Or via CLI:

openclaw mcp set nexo-brain '{"command":"python3","args":["~/.nexo/server.py"],"env":{"NEXO_HOME":"~/.nexo"}}'
openclaw gateway restart

ClawHub Skill

npx clawhub@latest install nexo-brain

Native Memory Plugin

npm install @wazionapps/openclaw-memory-nexo-brain

{
  "plugins": {
    "slots": {
      "memory": "memory-nexo-brain"
    }
  }
}

This replaces OpenClaw's default memory system with NEXO Brain's full cognitive architecture.

Any MCP Client

NEXO Brain works with any application that supports the MCP protocol. Configure it as an MCP server pointing to server.py inside NEXO_HOME (default ~/.nexo/server.py), with the NEXO_HOME env var set to the same directory.

Listed On

Directory	Type	Link
npm	Package	nexo-brain
Glama	MCP Directory	glama.ai
mcp.so	MCP Directory	mcp.so
mcpservers.org	MCP Directory	mcpservers.org
OpenClaw	Native Plugin	openclaw.com
dev.to	Technical Article	How I Applied Cognitive Psychology to AI Agents
Claude Code	Plugin (marketplace-ready)	Packaging verified, included in npm tarball
nexo-brain.com	Official Website	nexo-brain.com

Support the Project

If NEXO Brain is useful to you, consider:

• Star this repo — it helps others discover the project and motivates continued development
• Sponsor on GitHub — support ongoing development directly
• Share your experience — tell others how you're using cognitive memory in your AI workflows
• Contribute — see CONTRIBUTING.md for guidelines. Issues and PRs welcome
• Client parity / shared-brain maintenance — see docs/client-parity-checklist.md
• Writing a personal script that calls the automation backend — see docs/personal-scripts-guide.md

Memory Benchmark Snapshot

The full harness is in benchmarks/README.md. The first checked-in micro-benchmark compares the NEXO runtime against a static CLAUDE.md-only baseline on five recall-heavy scenarios:

Scenario	NEXO full stack	Static CLAUDE.md	No memory
Decision rationale recall	Pass	Partial	Fail
User preference recall	Pass	Partial	Fail
Repeat-error avoidance	Pass	Partial	Fail
Resume interrupted task	Pass	Partial	Fail
Related-context stitching	Pass	Fail	Fail

See benchmarks/results/memory-recall-vs-static.md for the rubric, prompt shape, and first-run notes.

Changelog

v3.0.1 — Python 3.10 Compatibility Patch (2026-04-06)

• Restored Python 3.10 compatibility by replacing Python 3.11-only datetime.UTC with timezone.utc.
• Added tomllib → tomli fallback plus declared runtime dependency for Python < 3.11.
• Boot doctor now validates all critical JSON config artifacts: schedule.json, optionals.json, crons/manifest.json.

v3.0.0 — Protocol Discipline, Durable Execution, Measured Runtime (2026-04-06)

• Protocol discipline runtime: Enforceable nexo_task_open/nexo_task_close, persistent protocol_debt, Cortex gates with durable check_id, conditioned-file guardrails across Claude hooks and Codex transcript audits.
• Durable workflow runtime: nexo_workflow_open/update/resume/replay/list with persistent runs, steps, checkpoints, replay history, retry bookkeeping, and idempotent open keys.
• Durable goals: nexo_goal_open/update/get/list for long-running work that stays active/blocked/abandoned/completed.
• Operational truth: Deep Sleep survives schema drift, keep_alive reports alive/degraded/duplicated honestly, warning storms no longer count as healthy.
• Measured product surface: 5-minute quickstart, Python SDK, reference verticals, measured compare scorecard with LoCoMo baselines and cost_per_solved_task.
• Skill lifecycle: Testing, promotion, retirement, and composition flows. Evolution public-core peer-review for opt-in PRs.

v2.7.0 — Shared Brain Baseline (2026-04-06)

• Managed Claude Code + Codex bootstrap with explicit CORE/USER contract.
• Codex config sync and transcript-aware Deep Sleep across both clients.
• 60-day long-horizon analysis, weekly/monthly summary artifacts.
• Retrieval auto-mode and first measured engineering loop.
• nexo chat opens the configured client instead of assuming Claude Code.

v2.6.9 — Integration Sync, CI/CD Pipeline (2026-04-04)

• Release artifact sync: Automated version synchronization across Claude Code plugin, OpenClaw package, and ClawHub skill before every publish.
• CI/CD pipeline: Full GitHub Actions workflow for publish + verification of all integration channels.
• OpenClaw plugin hardened: Contract tests, correct runtime path, synchronized version. Published as @wazionapps/openclaw-memory-nexo-brain@2.6.9.
• ClawHub skill hardened: Version-synced metadata, correct server path, post-publish smoke verification.
• Claude Code plugin packaging: Verified plugin.json, .mcp.json, hooks included in npm tarball. Marketplace-ready.

v2.6.5 — Power Helper Hardening, Recovery Contracts (2026-04-04)

• Power helper semantics explicit and safer: always_on = platform helper for best-effort background availability.
• Catch-up recovery suppresses duplicate relaunches for in-flight cron_runs.
• Runtime update/startup reconciles declared personal schedules automatically.

v2.6.3 — Cron Sync Fix, Hook Migration (2026-04-04)

• Runtime cron sync skips same-file copies, avoiding SameFileError on synced runtimes.
• Core hook migration normalizes legacy flat entries into Claude Code's required matcher + hooks[] format.

v2.6.2 — Startup Preflight, Personal Recovery, Power Policy (2026-04-04)

• Startup preflight before nexo chat and server — safe local migrations, deferred remote updates.
• Personal managed schedules can declare recovery contracts (wake/boot/catchup).
• Persisted runtime power policy (always_on/disabled/unset). Installer and nexo update prompt once.
• Packaged installs resolve update root correctly (fixes vunknown).

v2.6.0 — Personal Scripts Registry, Plugin Marketplace, Managed Evolution (2026-04-03)

• Personal scripts registry: Scripts in NEXO_HOME/scripts/ tracked in SQLite with metadata, categories, schedules. Full lifecycle: create, sync, reconcile, schedule, unschedule, remove.
• Orchestrator removed from core (breaking): Was opt-in personal automation adding complexity for all users. Existing users keep their setup in NEXO_HOME/scripts/.
• Claude Code plugin structure: plugin.json, entry point, packaging for marketplace submission.
• nexo chat: Official command to launch a NEXO terminal client, asking when multiple supported terminal clients are available.
• Managed Evolution hardening: Can modify core behavior modules with rollback followups.
• Cron recovery hardened: TCC diagnostics, keepalive sync, personal schedule catchup.

v2.5.0 — Runtime CLI, Doctor, Skills v2, Day Orchestrator (2026-04-03)

• Runtime CLI (nexo): New operational CLI separate from installer. nexo scripts list/run/doctor/call for personal scripts, nexo doctor for diagnostics, nexo skills apply for executable skills, nexo update for one-step sync.
• Unified Doctor: Modular diagnostic system with boot/runtime/deep tiers. Report-only by default, deterministic --fix mode. MCP tool nexo_doctor. LaunchAgent schedule drift detection and reconciliation.
• Skills v2: Executable skills with guide/execute/hybrid modes. Security levels (read-only/local/remote) with explicit approval. Core vs personal vs community directories. Deep Sleep auto-evolution integration.
• Day Orchestrator: Autonomous NEXO cycles every 15 min (8:00-23:00). Launches Claude Code headless with full MCP. Checks followups, emails, infra — acts autonomously, emails user only when needed. Opt-in.
• Dashboard always-on: Web UI at localhost:6174 as persistent LaunchAgent. 23 modules, Jinja2 templating, dark theme. Opt-in.
• Personal Scripts Framework: Auto-discovery in NEXO_HOME/scripts/, inline metadata, runtime detection, forbidden-pattern validation, vendorable helper, template.
• Configurable operator name (UserContext singleton), watchdog normalized to 30 min, LaunchAgent drift fix.

v2.4.0 — Skills, Cron Scheduler, Security, Full Audit (2026-04-03)

• Skill Auto-Creation: Deep Sleep extracts reusable procedures from sessions. Content stored as markdown with steps and gotchas. Trust pipeline with autonomous quality control.
• Cron Scheduler: execution tracking (cron_runs table), nexo_schedule_status and nexo_schedule_add MCP tools, universal cron wrapper for all processes.
• Deep Sleep v2.4: watermark-based collection (late-night sessions included), per-session checkpointing (crash-safe), retry x3, JSON parsing fix, auto-calibration of personality settings.
• Security: credential redaction in tool logs, transcript sanitization, command injection fix in dashboard, path traversal protection in plugin loader.
• Diary filter: startup only shows human sessions, auto-closed cron sessions filtered out. Email sessions preserved as real interactions.
• Preflight CI: 66 automated checks (py_compile, bash -n, manifest consistency, npm artifact, forbidden markers).
• Python 3.9 compat: from __future__ import annotations across 18 files.
• Linux: full systemd timer support, .bashrc alias for interactive shells.
• Passed 5-phase automated audit: Product, Failure, Security, Packaging, UX.

v2.2.0 — Trust Score v2 (2026-04-01)

• Trust Score: fair daily calibration from Deep Sleep analysis. Score 0-100 based on corrections, autonomy, proactivity.
• Cognitive Quarantine: new memories go through quarantine before promotion to LTM.

v2.0.0 — Unified Architecture (2026-03-31)

• Code/data separation: Code in repo (src/), personal data in NEXO_HOME (default ~/.nexo/). NEXO_HOME env var required.
• Plugin loader dual-directory: Scans src/plugins/ (base) then NEXO_HOME/plugins/ (personal override by filename).
• Auto-update on startup: Non-blocking (5s max), resilient, opt-out via schedule.json. Separate from manual nexo_update tool.
• Auto-diary: 3-layer system — PostToolUse every 10 calls, PreCompact emergency save, heartbeat DIARY_OVERDUE signal.
• CLAUDE.md version tracker: Section markers enable safe core updates without losing user customizations.
• schedule.json: Customizable process schedules with timezone support and auto_update flag.
• 15 autonomous processes: Added auto-close-sessions, synthesis, backup, tcc-approve, prevent-sleep (cross-platform).
• 7 hooks: SessionStart (timestamp + briefing), Stop, PostToolUse (capture + inbox), PreCompact, PostCompact.
• 150+ MCP tools: Added nexo_update tool for manual updates with rollback.
• Lambda fix: Decay values were 24x too aggressive (STM: 7h to 7d, LTM: 2.4d to 60d).
• Guard scoping: Was returning 35+ irrelevant blocking rules; now scoped to area and gated to high/critical.
• 12 rounds of external audit: ~60 findings resolved.

v1.7.0 — Full Internationalization + Linux Support (2026-03-31)

• Full i18n: All UI strings, error messages, DB status values in English. NLP detection patterns retain bilingual keywords (Spanish + English) for multilingual user support.
• Linux support: systemd user timers (preferred) or crontab fallback for all automated cognitive processes.
• Auto-resolve followups: Change log entries automatically cross-reference and complete matching open followups.
• Free-form learning categories: No more hardcoded category validation — use any category name.
• CLAUDE.md template rewrite: 494 to 127 lines, compact procedural format with full heartbeat signal reactions.
• Complete sanitization: All hardcoded paths use NEXO_HOME env var. No credentials or personal data in the distributed package. Migration scripts and maintainer tooling use configurable paths.

v1.6.0 — Nervous System + Dashboard v2 (2026-03-30)

• Nervous System: 11 autonomous scripts (decay, deep sleep, self-audit, catchup, evolution, followup hygiene, immune, watchdog, github monitor, learning validator)
• Dashboard v2: 6 interactive pages at localhost:6174 (Overview, Graph, Memory, Somatic, Adaptive, Sessions)
• LaunchAgent Templates: macOS automation templates included in the package for scheduling the nervous system
• Hooks: 7 total — SessionStart, Stop, PostToolUse, PreCompact, PostCompact
• Installer: Now configures dashboard LaunchAgent, nervous system scripts, and all templates automatically

v1.5.2 — Deep Sleep (2026-03-29)

• Deep Sleep: Reads full session transcripts (not just diary) — finds uncaptured corrections, protocol violations, missed commitments
• Uses Claude CLI in --bare mode (no hooks, no CLAUDE.md interference)
• Catch-up system re-runs yesterday if the Mac was off

v1.5.0 — Modular Core + Knowledge Graph Search (2026-03-29)

• Architecture: db.py refactored into db/ package (11 modules); cognitive.py into cognitive/ package (6 modules)
• KG Boost: Knowledge Graph connection count influences search result ranking
• HNSW Vector Index: Optional approximate nearest neighbor acceleration (auto-activates above 10,000 memories)
• Claim Graph: Decomposes blob memories into atomic verifiable facts with provenance and contradiction detection
• Inter-terminal Auto-inbox (D+): nexo_startup accepts claude_session_id for automatic inbox delivery between parallel terminals
• Tests: 156 pytest tests across 3 suites (cognitive, knowledge graph, migrations)

v1.4.1 — Multi-AI Code Review (2026-03-29)

• Fix: 3 bugs found by GPT-5.4 (Codex CLI) + Gemini 2.5 (Gemini CLI) reviewing full codebase
• Security: Memory sanitization prevents prompt injection via stored content
• Migration #13: Normalizes legacy status values on upgrade

v1.4.0 — The Brain Dreams (2026-03-29)

• Major: All 9 nightly scripts migrated from Python word-overlap to CLI wrapper pattern
• Stop Hook v8: Session-scoped tool counting, buffer fallback removed
• Guard: Behavioral rules section surfaces most-violated rules at session start

v1.3.0 — Evolution System (2026-03-28)

• New: Self-improvement cycle — NEXO proposes and applies improvements weekly
• Dual-mode: auto (low-risk) and review (owner approval required)
• Circuit breaker, snapshot/rollback, immutable file protection

v1.2.3 — AGPL-3.0 License (2026-03-27)

• License changed from MIT to AGPL-3.0

v1.2.1 — Stop Hook Hotfix (2026-03-27)

• Fix: v1.2.0 deleted the flag on approve, causing infinite block loops if session didn't close immediately
• Fix: Removed TTL on flag — it persists until SessionStart cleans it up next session
• New: Trivial sessions (<5 meaningful tool calls) skip post-mortem entirely and approve immediately
• SessionStart hook now cleans up .postmortem-complete flag on session start

v1.2.0 — Blocking Stop Hook (2026-03-27)

• Fix: Stop hook now uses "decision": "block" instead of "approve" to enforce post-mortem execution
• Previous behavior: hook injected systemMessage but AI had already responded — instructions were never processed
• New behavior: session close is blocked until AI completes self-critique, session diary, buffer entry, and followups
• Flag-based mechanism (.postmortem-complete) allows second close attempt to succeed
• Works for all NEXO users, not just specific setups

v1.1.1 — Multi-terminal fix (2026-03-27)

• Fix: PostCompact now reads the correct session's checkpoint in multi-terminal setups
• Changelog section added to README

v1.1.0 — Context Continuity (2026-03-27)

• Context Continuity: PreCompact/PostCompact hooks preserve session state across compaction events
• New session_checkpoints SQLite table + migration #12
• New tools: nexo_checkpoint_save, nexo_checkpoint_read
• Heartbeat automatically maintains checkpoint every interaction
• Core Memory Block re-injected post-compaction with task, files, decisions, reasoning thread
• 115+ total tools at the time, 20 categories

v1.0.0 — Cognitive Cortex + Stable Release (2026-03-26)

• Cognitive Cortex: architectural inhibitory control (ASK/PROPOSE/ACT modes)
• 30 Core Rules as immutable DNA in SQLite
• Designed via 3-way AI debate (Claude Opus + GPT-5.4 + Gemini 3.1 Pro)
• Artifact Registry for operational facts
• Full benchmark suite (LoCoMo F1: 0.588)

v0.10.0 — Smart Context (2026-03-22)

• Smart Startup: pre-loads memories from pending followups + diary
• Context Packet: structured injection for subagents
• Auto-Prime: keyword-triggered area learnings in heartbeat
• Diary Archive: permanent subconscious memory (180d+ auto-archived)

v0.9.0 — Cognitive Memory (2026-03-15)

• Atkinson-Shiffrin memory model (STM → LTM promotion)
• Semantic RAG with pinned local multilingual fastembed models
• Trust scoring, sentiment detection, adaptive personality modes
• Ebbinghaus decay, sister detection, quarantine system

License

AGPL-3.0 -- see LICENSE

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Created by Francisco Cerdà Puigserver & NEXO (Claude Opus) · Built by WAzion