AnchorMD

Persistent project context for AI coding agents using linked markdown plans with relationship tracking and hybrid search.

Prerequisites

AnchorMD requires Bun runtime.

curl -fsSL https://bun.sh/install | bash

macOS: For full search support (semantic + hybrid), install Homebrew SQLite:

brew install sqlite

This is needed because macOS ships with Apple's SQLite which doesn't support extension loading. Lexical search (BM25) works without it.

Install

bun add -g anchormd

Quick Start

# Initialize in your project
anchormd init

# Edit the project overview
anchormd write anchor

# Create a plan
echo '---
name: auth
description: Authentication system
status: planned
---
# Authentication

JWT-based auth. See [[database]] for schema.
Uses POST /api/auth/login endpoint.
Config in src/auth/config.ts.
' | anchormd write auth

# View project context
anchormd context

# List all plans
anchormd ls

# Read a specific plan
anchormd read auth

# Read a specific section
anchormd read auth#authentication

# View project stats
anchormd status

Commands

| Command | Description | |---------|-------------| | anchormd init [--no-qmd] | Initialize AnchorMD in the current project | | anchormd context | Print project overview and plan summary table | | anchormd write <name> [--from <file>] | Write or update a plan (reads from file, stdin, or editor) | | anchormd ls [--status <s>] [--json] | List all plans, optionally filtered by status | | anchormd read <name[#section]> | Read a plan or a specific section via deep link | | anchormd find <query> [--semantic] [--hybrid] [--limit <n>] [--json] | Search plans with deep links to matching sections | | anchormd reindex | Rebuild the index graph and search database | | anchormd status | Show plan count, links, weak edges, and QMD status |

How It Works

Plans

Plans are markdown files with YAML frontmatter stored in .anchor/plans/. Each plan has:

• name: identifier used in links
• description: short summary
• status: one of planned, in-progress, built, deprecated
• tags: optional array of tags

Links

Plans reference each other using wiki-style links:

• Strong links: [[plan-name]] creates an explicit edge in the graph
• Deep links: [[plan-name#section]] links to a specific section

Entities

AnchorMD extracts entity references from plan content:

• File paths: src/auth/config.ts, lib/utils.js
• Models: model User, UserSchema
• Routes: GET /api/users, POST /api/auth/login
• Scripts: deploy.sh, npm run build

Weak Edges

When two plans reference the same entity (e.g., both mention src/auth/config.ts), AnchorMD creates a weak edge between them. This surfaces implicit relationships that weren't explicitly linked.

Index Graph

The index graph (.anchor/index.json) tracks all plans, their links, entities, and weak edges. It's rebuilt automatically when plans are written, or manually via anchormd reindex.

Search

AnchorMD uses QMD for search. Three modes are available:

• Lexical (default): BM25 keyword search — fast, no dependencies beyond SQLite
• Semantic: Vector similarity search — requires sqlite-vec (brew install sqlite on macOS)
• Hybrid: Combined lexical + semantic with LLM reranking

Search results include deep links to the most relevant section:

$ anchormd find "sentiment analysis"
  1. [0.823] myproject/analytics-prd.md
     → analytics-prd#sentiment-tab

Use the deep link directly: anchormd read analytics-prd#sentiment-tab

Configuration

Configuration is stored in .anchor/config.json:

{
  "qmd": true,
  "collectionName": "my-project"
}

• qmd: Enable/disable QMD search integration (enabled by default)
• collectionName: Project's collection name in the central search database (auto-derived from directory name)

Central Search Database

AnchorMD stores all search data in a single central database at ~/.anchormd/anchormd.sqlite. Each project is registered as a named collection, enabling:

• No per-project SQLite files to gitignore
• Collection-scoped search (each project only sees its own plans)
• Future cross-project search capabilities

Upgrading from v0.1.x

If you used an earlier version with per-project .anchor/search.sqlite:

bun add -g anchormd@latest
anchormd reindex  # auto-migrates to central DB

The old .anchor/search.sqlite can be safely deleted.

Claude Code Integration

AnchorMD ships with a skill file at skill/SKILL.md for integration with Claude Code. The skill teaches Claude to:

1. Run anchormd context at session start
2. Search for relevant plans before starting tasks
3. Read plan details as needed
4. Update plans after implementing changes

Project Structure

.anchor/
  config.json       # Project configuration
  index.json        # Relationship graph
  plans/
    anchor.md       # Project overview (created on init)
    *.md            # Your plan files

~/.anchormd/
  anchormd.sqlite   # Central search database (shared across all projects)

License

MIT