Clearly

Markdown editor and knowledge base for Mac.

Mac App Store · Direct Download · Website · @Shpigford

Write with syntax highlighting, link your thoughts with wiki-links, search everything, preview beautifully. Native macOS, no Electron, no subscriptions.

Features

Writing

• Syntax highlighting — headings, bold, italic, links, code blocks, tables, highlighted as you type
• Format shortcuts — ⌘B bold, ⌘I italic, ⌘K links
• Extended markdown — ==highlights==, ^superscript^, subscript, :emoji: shortcodes, [TOC] generation
• Scratchpad — menubar scratch pad with a global hotkey

Knowledge

• Wiki-links — link documents with [[wiki-links]], type [[ to autocomplete
• Backlinks — linked and unlinked mentions with one-click linking
• Tags — organize with #tags, browse in the sidebar
• Global search — full-text search across every document, ranked by relevance
• Document outline — navigable heading outline, click to jump
• File explorer — browse folders, bookmark locations, create and rename files

Preview

• GFM rendering — tables, task lists, footnotes, strikethrough
• KaTeX math — inline and block equations
• Mermaid diagrams — flowcharts, sequence diagrams from code blocks
• Code blocks — 27+ languages, line numbers, diff highlighting, one-click copy
• Callouts — NOTE, TIP, WARNING, and 15+ types, foldable
• Interactive — toggle checkboxes, zoom images, hover footnotes, double-click to jump to source

Integration

• AI / MCP server — built-in MCP server and clearly CLI expose your vault to AI agents. See clearly CLI and ClearlyMCP.
• QuickLook — preview .md files in Finder with Space
• PDF export — export or print, page breaks handled
• Copy formats — markdown, HTML, or rich text

Screenshots

Prerequisites

• macOS 14 (Sonoma) or later
• Xcode 16+ with command-line tools (xcode-select --install)
• Homebrew (brew.sh)
• xcodegen — brew install xcodegen

Dependencies (cmark-gfm, Sparkle, GRDB, MCP SDK) are pulled automatically by Xcode via Swift Package Manager.

Quick Start

git clone https://github.com/Shpigford/clearly.git
cd clearly
brew install xcodegen    # skip if already installed
xcodegen generate        # generates Clearly.xcodeproj from project.yml
open Clearly.xcodeproj   # opens in Xcode

Then hit ⌘R to build and run.

The Xcode project is generated from project.yml. If you change project.yml, re-run xcodegen generate. Don't edit the .xcodeproj directly.

CLI build

xcodebuild -scheme Clearly -configuration Debug build

Project Structure

Clearly/
├── ClearlyApp.swift                # @main — DocumentGroup + menu commands (⌘1/⌘2)
├── MarkdownDocument.swift          # FileDocument conformance for .md files
├── ContentView.swift               # Mode picker, Editor ↔ Preview switching
├── EditorView.swift                # NSViewRepresentable wrapping NSTextView
├── MarkdownSyntaxHighlighter.swift # Regex-based highlighting via NSTextStorageDelegate
├── PreviewView.swift               # NSViewRepresentable wrapping WKWebView
├── FileExplorerView.swift          # Sidebar file browser with bookmarks and recents
├── FileParser.swift                # Parses frontmatter, wiki-links, tags from documents
├── VaultIndex.swift                # SQLite + FTS5 index for search, backlinks, tags
├── CLIInstaller.swift              # Installs ~/.local/bin/clearly symlink from Settings
├── Theme.swift                     # Centralized colors (light/dark) and font constants
└── Info.plist

ClearlyQuickLook/
├── PreviewProvider.swift           # QLPreviewProvider for Finder previews
└── Info.plist

ClearlyCLI/                         # `clearly` CLI binary + MCP server
├── CLI/                            #   ArgumentParser subcommands + global options
├── Core/                           #   Pure-function tool implementations
└── MCP/                            #   MCP adapter (tool registry + dispatch)

ClearlyCLIIntegrationTests/         # XCTest suite driving MCP server in-process
├── FixtureVault/                   #   Sample .md files exercising every tool
└── *.swift                         #   Per-tool + schema + error + path-guard tests

Shared/
├── MarkdownRenderer.swift          # cmark-gfm → HTML + post-processing pipeline
├── PreviewCSS.swift                # CSS for in-app preview and QuickLook
├── MathSupport.swift               # KaTeX injection
├── MermaidSupport.swift            # Mermaid injection
├── SyntaxHighlightSupport.swift    # Highlight.js injection
├── EmojiShortcodes.swift           # :shortcode: → Unicode lookup
├── FrontmatterSupport.swift        # Shared YAML frontmatter parser
└── Resources/                      # Bundled JS/CSS, demo.md

website/                            # Static site deployed to clearly.md
scripts/                            # Release pipeline + CLI smoke test
project.yml                         # xcodegen config (source of truth)

Architecture

SwiftUI + AppKit, document-based app with four targets.

Targets

1. Clearly — main app. DocumentGroup with MarkdownDocument, editor and preview modes, file explorer, vault indexing.
2. ClearlyQuickLook — Finder extension for previewing .md files with Space.
3. ClearlyCLI — the clearly CLI binary and MCP server (same executable, different arg parser). Exposes 9 tools across read and write. See clearly CLI and ClearlyMCP.
4. ClearlyCLIIntegrationTests — XCTest suite driving the MCP server in-process via InMemoryTransport. Runs on every PR via .github/workflows/test.yml.

Editor

Wraps AppKit's NSTextView via NSViewRepresentable — not SwiftUI's TextEditor. This provides native undo/redo, the system find panel (⌘F), and NSTextStorageDelegate-based syntax highlighting on every keystroke.

Preview

PreviewView wraps WKWebView and renders HTML via MarkdownRenderer (cmark-gfm). Post-processing pipeline: math → highlight marks → superscript/subscript → emoji → callouts → TOC → tables → code highlighting.

Knowledge Graph

VaultIndex maintains a SQLite database with FTS5 for full-text search. FileParser extracts wiki-links, backlinks, and tags from documents. The index is built on a background thread via WorkspaceManager to avoid blocking the UI.

Dependencies

Package	Purpose
cmark-gfm	GitHub Flavored Markdown → HTML
Sparkle	Auto-updates (direct distribution only)
GRDB	SQLite + FTS5 for vault indexing
MCP	Model Context Protocol server
swift-argument-parser	CLI parsing for clearly

Key Decisions

• AppKit bridge — NSTextView over TextEditor for undo, find, and NSTextStorageDelegate syntax highlighting
• Dynamic theming — all colors through Theme.swift with NSColor(name:) for automatic light/dark
• Shared code — MarkdownRenderer and PreviewCSS compile into both the main app and QuickLook
• Dual distribution — Sparkle for direct, App Store without. All Sparkle code wrapped in #if canImport(Sparkle)
• No .inspector() — outline panel uses HStack due to fullscreen safe area bugs

Common Dev Tasks

Change syntax highlighting

Edit MarkdownSyntaxHighlighter.swift. Patterns are applied in order — code blocks first, then everything else.

Modify preview styling

Edit Shared/PreviewCSS.swift. Used by both in-app preview and QuickLook. Keep in sync with Theme.swift colors. Base styles must come before @media (prefers-color-scheme: dark) overrides.

Add a preview feature

Follow the MathSupport/MermaidSupport pattern: create a *Support.swift enum in Shared/ with a static method that returns a <script> block. Integrate into PreviewView.swift, PreviewProvider.swift, and PDFExporter.swift.

Testing

Automated:

xcodebuild test -scheme ClearlyCLIIntegrationTests -destination 'platform=macOS'
./scripts/cli-smoke.sh

CI runs both on every pull request (.github/workflows/test.yml).

Manual:

1. Build and run (⌘R)
2. Open a .md file — verify syntax highlighting
3. Switch to preview (⌘2) — verify rendered output
4. Test wiki-links, backlinks, search, tags
5. QuickLook: select a .md in Finder, press Space
6. Check both light and dark mode

clearly CLI

The clearly command-line binary is bundled with Clearly.app and operates on the same SQLite index the app maintains — no separate configuration, no data duplication.

Install

Open Clearly → Settings → Command Line → Install. Creates a symlink at ~/.local/bin/clearly pointing to the bundled binary inside Clearly.app/Contents/Resources/Helpers/ClearlyCLI. No admin password needed — everything stays in your home folder.

If ~/.local/bin isn't already on your shell PATH, add this to ~/.zprofile (or your shell's equivalent) and open a new terminal:

export PATH="$HOME/.local/bin:$PATH"

Upgrades (Sparkle or App Store) keep the symlink valid. Uninstall from the same Settings pane.

Legacy /usr/local/bin/clearly installs from Clearly ≤ 2.4.x keep working and are detected automatically — no action needed.

Subcommand reference

clearly
├── mcp                 Start the MCP stdio server (this is what MCP clients invoke)
├── search <query>      Full-text search; emits NDJSON hits
├── read <path>         Read a note + metadata (hash, size, mtime, frontmatter, headings, tags)
├── list                List notes as NDJSON (fresh filesystem walk)
├── headings <path>     Heading outline (level, text, line_number)
├── frontmatter <path>  Parsed YAML frontmatter (flat key-value)
├── backlinks <path>    Linked references + unlinked mentions
├── tags [<tag>]        All tags with counts, or files for one tag
├── create <path>       Create a new note from --content or --from-stdin
├── update <path>       Update with --mode replace|append|prepend
├── vaults [list]       List loaded vaults (name, path, file_count, last_indexed_at)
└── index [rebuild]     Rebuild the SQLite index from disk

Run clearly <subcommand> --help for flags, examples, and output-shape notes.

Exit codes

Code	Name	Meaning
0	success	Command completed; output on stdout
1	general	Generic failure (e.g. no vaults loaded, non-UTF8 file)
2	usage	Invalid arguments / missing required flags
3	notFound	Note or vault filter not found
4	permission	Path resolves outside vault (traversal, /absolute, unicode lookalikes)
5	conflict	Note already exists (on create) or ambiguous across vaults

Output contract

• JSON mode (default): every tool emits a stable structured shape documented per-tool in its --help. List-shaped commands (search, list, tags) emit NDJSON — one record per line — for stream-friendly piping. Keys are snake_case.
• Text mode (--format text): human-readable aligned output, no stability guarantees. Use for terminal eyeballing only; agents and scripts should stick with JSON.
• Errors always go to stderr as a structured JSON object with error (stable identifier), message (human text), and relevant context fields. See the error identifiers table.

Pipeline examples

# Top 20 tag counts, sorted
clearly tags | jq -s 'sort_by(-.count) | .[:20]'

# Grep every note under Projects/ for a term
clearly list --under Projects/ \
  | jq -r '.relative_path' \
  | xargs -I{} sh -c 'clearly read "{}" | jq -r ".content" | grep -l -e "OKR" /dev/stdin && echo "{}"'

# Cache invalidation by content hash
OLD=$(clearly read Notes/plan.md | jq -r '.content_hash')
# ...edit the file...
NEW=$(clearly read Notes/plan.md | jq -r '.content_hash')
[ "$OLD" != "$NEW" ] && echo "rebuild"

Troubleshooting

• Multi-vault ambiguity — pass --in-vault <name> on per-command calls, or --vault <path> on the global command to scope which vault(s) to load.
• Custom bundle id — --bundle-id com.sabotage.clearly.dev to point at the Debug build's vault store.
• Dev-build SIGKILL — the bundled ClearlyCLI inside Clearly Dev.app/Contents/Resources/Helpers/ gets SIGKILL'd by macOS when launched standalone (code-signature invalidation). Use the product binary at Build/Products/Debug/ClearlyCLI directly for local testing.

ClearlyMCP

Same binary, different arg — clearly mcp starts a stdio MCP server exposing 9 tools to any Model Context Protocol client.

Client config

Claude Desktop (~/Library/Application Support/Claude/claude_desktop_config.json):

{
  "mcpServers": {
    "clearly": {
      "command": "/Users/you/.local/bin/clearly",
      "args": ["mcp"]
    }
  }
}

Claude Code (~/.config/claude-code/mcp.json or via claude mcp add):

{
  "mcpServers": {
    "clearly": {
      "command": "/Users/you/.local/bin/clearly",
      "args": ["mcp"]
    }
  }
}

Cursor (~/.cursor/mcp.json):

{
  "mcpServers": {
    "clearly": {
      "command": "/Users/you/.local/bin/clearly",
      "args": ["mcp"]
    }
  }
}

Settings → Command Line → Copy MCP config in the Clearly app copies a ready-to-paste snippet with the correct path for your machine (flips to ~/.local/bin/clearly once the symlink is installed, or the legacy /usr/local/bin/clearly path if you're on an older install).

Tool reference

All tools use snake_case JSON keys on input and output. Every response also includes a structuredContent field on success and isError: true on failure — both mirror the text content exactly. Error responses include error (stable identifier) and message.

Tool	Annotations	Summary
search_notes	read-only, idempotent	Full-text search (BM25). Returns ranked hits with excerpts.
read_note	read-only, idempotent	Full content + hash, size, mtime, frontmatter, headings, tags. Optional line range.
list_notes	read-only, idempotent	Fresh filesystem walk. Optional under prefix.
get_headings	read-only, idempotent	Heading outline (level 1–6, text, line_number).
get_frontmatter	read-only, idempotent	Parsed YAML frontmatter as a flat map.
get_backlinks	read-only, idempotent	Linked references (via [[WikiLink]]) plus unlinked mentions.
get_tags	read-only, idempotent	All tags with counts, or files per tag.
create_note	destructive, non-idempotent	New note at a vault-relative path. Conflict on existing.
update_note	destructive, non-idempotent	replace / append / prepend modes. Prepend is frontmatter-aware.

Each tool registers its full JSON Schema via MCP outputSchema; clients that render schemas (MCP Inspector, the Claude API tool-call viewer) can introspect every field without reading source.

Example payloads

search_notes (NDJSON, one hit per line):

{"excerpts":[{"context_line":"# The Death of SaaS Pricing Pages","line_number":8},{"context_line":"Pricing pages are broken…","line_number":10}],"filename":"The Death of SaaS Pricing Pages","matches_filename":true,"relative_path":"Blog Posts/The Death of SaaS Pricing Pages.md","vault":"Documents","vault_path":"/Users/…/Documents"}

read_note:

{
  "content": "---\ntitle: Building in Public is a Lie\ndate: 2026-03-15\n---\n\n# Building in Public is a Lie\n…",
  "content_hash": "e9777e4a4e308a77ec7c5814f4d4204c978139249967deb064b4558bf4f2594a",
  "frontmatter": { "date": "2026-03-15", "status": "draft", "tags": "writing, transparency", "title": "Building in Public is a Lie" },
  "headings": [{ "level": 1, "line_number": 8, "text": "Building in Public is a Lie" }],
  "size_bytes": 1703,
  "modified_at": "2026-04-14T15:47:25.274Z",
  "relative_path": "Blog Posts/Building in Public is a Lie.md",
  "vault": "Documents"
}

get_backlinks:

{
  "linked": [
    { "display_text": "my piece on transparency", "line_number": 23, "relative_path": "Blog Posts/The Death of SaaS Pricing Pages.md", "vault": "Documents" }
  ],
  "unlinked": [],
  "relative_path": "Blog Posts/Building in Public is a Lie.md",
  "vault": "Documents"
}

get_tags (all tags, NDJSON):

{"count":1,"tag":"ai"}
{"count":33,"tag":"analysis"}

Error identifiers

Every error response — whether emitted by the CLI to stderr or by the MCP server as structuredContent with isError: true — uses one of these identifiers:

error	Where it fires	Context fields
missing_argument	Required flag/arg not provided	argument
invalid_argument	Bad value (e.g. --mode not one of replace/append/prepend)	argument, reason
invalid_encoding	File is not valid UTF-8	relative_path
note_not_found	Target note doesn't exist in any loaded vault	relative_path
path_outside_vault	Path resolves outside the vault (traversal, absolute, unicode lookalike)	relative_path
ambiguous_path	Multiple loaded vaults contain this path	relative_path, matches
note_exists	create_note against an existing path	relative_path
no_vaults	CLI-only: could not open any vault index	bundle_id
no_vault_match	--in-vault filter didn't match any loaded vault	filter
unknown_tool	MCP tools/call for an unregistered tool name	tool
internal_error	Uncategorized exception from a tool	error_type

The identifier is the stable contract — agent code should branch on error, not on message text.

License

FSL-1.1-MIT — see LICENSE. Code converts to MIT after two years.