legendary-mcp 0.1.0

Code-anchored, staleness-aware, git-native memory for coding agents.

Documentation  ·  Quickstart  ·  Concepts  ·  MCP tools  ·  Comparison

Coding agents are stateless: every session re-reads your repo, re-derives old decisions, and repeats debugging attempts that already failed. Memory frameworks remember conversations but are code-blind - a memory never knows it was about src/sync/worker.py:120 and never notices when that code changes.

legendary merges the two sides:

• Anchored - memories link to a file / symbol / line range at a commit
• Staleness-aware - when the anchored code changes, recall flags the memory stale; when it disappears, orphaned
• Typed - decision (why it is this way), episode (tried X, failed because Y), convention, reference
• Git-native - memories are markdown files in .legendary/memories/, committed with your code, diffable in PRs, shared with your whole team
• Local-first - no cloud, no accounts, no API keys, no embeddings; SQLite FTS5 does search

The 30-second demo

$ legendary recall "strip None"
strip() breaks on None   [fresh]

$ vim app.py     # edit the anchored function

$ legendary recall "strip None"
strip() breaks on None   [stale - parse changed since 8fa2c31]

That flag is the whole point. Every other memory system would still serve you that memory with full confidence.

Quick start

cd your-repo
uvx --from legendary-mcp legendary init   # scaffolds .legendary/, prints MCP + hook setup

Add the printed MCP snippet to your client (Claude Code, Cursor, any MCP host). Your agent now has five tools:

Optional auto-capture (Claude Code): the printed hooks run legendary inject at session start (context injection) and legendary extract at session end (LLM pass over the transcript, saved with source: auto-extract provenance).

CLI

legendary init | search <q> | reindex | doctor | extract [transcript] | inject | mcp

legendary mcp serves stdio by default; --transport http serves stateless streamable HTTP for containers and shared team deployments.

How staleness works

At write time each anchor stores a normalized content hash of the anchored region (symbol body, line range, or file). At recall time the region is re-resolved (symbols may move) and re-hashed. Changed hash => stale; missing file/region => orphaned. Stale memories still surface - the why often survives a refactor - but ranked lower and clearly flagged.

Whitespace-only changes do not invalidate a memory, and a symbol that merely moves down the file stays fresh, because anchors are re-resolved by symbol before hashing.

Architecture

flowchart TB
    subgraph host["MCP host - Claude Code / Cursor / Codex / any"]
        agent["Coding agent"]
    end

    subgraph legendary["legendary (uvx --from legendary-mcp)"]
        mcp["MCP server<br/>remember - recall - list_memories<br/>deprecate - stale_report"]
        cli["CLI<br/>init - search - reindex - doctor<br/>extract - inject"]
        svc["service layer"]
        subgraph core["core"]
            store["markdown store"]
            index["SQLite FTS5 index"]
            anchor["anchor resolve + hash"]
            stale["staleness verdicts"]
            rank["weighted ranking"]
        end
    end

    subgraph repodir[".legendary/ in your repo"]
        md["memories/*.md - committed"]
        db["index.db - gitignored"]
    end

    agent -- "MCP tools (stdio)" --> mcp
    agent -. "session hooks" .-> cli
    mcp --> svc
    cli --> svc
    svc --> store
    svc --> index
    svc --> anchor
    svc --> stale
    svc --> rank
    store --> md
    index --> db

stateDiagram-v2
    [*] --> fresh: remember() - region hashed at commit X
    fresh --> stale: anchored region edited
    stale --> fresh: memory re-anchored
    fresh --> orphaned: file / symbol deleted
    stale --> orphaned: file / symbol deleted
    fresh --> deprecated: deprecate(reason)
    stale --> deprecated: deprecate(reason)
    orphaned --> deprecated: doctor cleanup

What a memory looks like

---
id: mem-a1b2c3d4
type: episode
title: Retry logic in sync worker breaks under SQLite WAL
created: 2026-08-14T15:30:00Z
source: agent
status: active
anchors:
  - file: src/sync/worker.py
    symbol: SyncWorker.run
    lines: [120, 164]
    commit: 8fa2c31
    content_hash: sha256:9f8e...
tags: [sqlite, concurrency]
---
Tried wrapping retries in a transaction (attempt 1) - deadlocks under WAL.
Working approach: PRAGMA busy_timeout.

Human-readable, PR-reviewable, and it merges like code.

How this differs from other tools

Code-graph tools answer "what is this code?"; legendary answers "what do we already know about it, and is that still true?" Running both is a good setup.

Documentation

Full docs at ashhadahsan.github.io/legendary — quickstart, concepts, MCP tool reference, CLI reference, benchmark, and FAQ.

Contributing? See CONTRIBUTING.md.

License

MIT