King Crimson MCP Server

King Crimson Discography MCP Server

日本語版: README.ja.md

An MCP server that surfaces King Crimson record and live-performance data — including a curated incarnation (line-up era) model that shows how each song belongs to specific eras of the band.

What makes this different

Generic MusicBrainz/Discogs MCP servers can already fetch releases, credits, and pressings. This server does that too, but adds two things a band-agnostic discography tool structurally can't have:

• A cross-source integration layer keyed on MBID. MusicBrainz, Discogs, Cover Art Archive, and setlist.fm are stitched together so one release-group MBID gets you credits, physical editions, artwork, and live history without re-resolving identities per source.

• A King Crimson incarnation model. King Crimson's line-up turned over almost completely, many times, over five decades — the same song can mean a totally different band depending on the year. This server hand-curates eight line-up eras and cross-references every tracked song's live-performance history against them:

  Song	Incarnations it appears in
  "21st Century Schizoid Man"	Spread across every era — the band's signature
  "Starless"	Only the Larks' Tongues era and the Three-drummer era
  "Elephant Talk"	Born in the Discipline era, gone by the Three-drummer era

• A local, offline-first concert cache. Full concert history (1,200+ shows) is fetched once via refresh_setlist_cache and cached as JSON. Every subsequent song/tour/era query reads the cache — instant, and immune to setlist.fm's intermittent rate-limit failures during analysis.

Tools

The incarnation model

Eight line-up eras, split on membership changes:

Boundaries are dates, not just years — 1972 in particular splits into the Islands-era "Earthbound" spring tour (Transitional) and the Wetton-era autumn tour (Larks' Tongues), since the band's membership genuinely changed mid-year.

Line-up eras are a matter of fan interpretation, and this is one reasonable cut, not the only one. The full definition lives in KING_CRIMSON_INCARNATIONS in src/king_crimson_mcp/server.py — edit it (members, key releases, date boundaries) to match your own view; the aggregation logic doesn't need to change.

Quick start

You don't need to be a programmer. Three one-time steps, then it runs inside Claude.

Step 1 — Install uv (one time)

uv is a small tool that can fetch and run this server for you.

• macOS / Linux:

  curl -LsSf https://astral.sh/uv/install.sh | sh
  

• Windows (PowerShell):

  powershell -c "irm https://astral.sh/uv/install.ps1 | iex"
  

Close and reopen your terminal afterward. To check it worked:

uv --version

Step 2 — Get your free API keys

This server reads public music databases. Two of them need a free key:

• setlist.fm (live performance history) — apply for a key at https://api.setlist.fm/docs/1.0/index.html
• Discogs (physical editions) — create a token at Discogs → Settings → Developers → Generate token

You also set a contact email (MCP_CONTACT) — MusicBrainz requires this so their servers know who's calling. Any email you own is fine.

(MusicBrainz and Cover Art Archive need no key.)

Step 3 — Add it to Claude Desktop

Open Claude Desktop's config file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json

Add this (fill in your email and keys):

{
  "mcpServers": {
    "king-crimson": {
      "command": "uvx",
      "args": ["king-crimson-mcp"],
      "env": {
        "MCP_CONTACT": "you@example.com",
        "SETLISTFM_API_KEY": "your-setlistfm-key",
        "DISCOGS_TOKEN": "your-discogs-token"
      }
    }
  }
}

Restart Claude Desktop. King Crimson tools will appear automatically — you don't run anything in a terminal yourself.

Step 4 — First use

In Claude, ask something like "Refresh the King Crimson setlist cache" once (it downloads the full concert history, ~40 seconds). After that, try "Show me the performance history of Starless" or "Which incarnations played 21st Century Schizoid Man?"

Troubleshooting

• "uvx: command not found" / server won't start in Claude Desktop. uv isn't installed or isn't on your PATH. Redo Step 1, then fully quit and reopen Claude Desktop. On Windows you may need the full path to uvx in the command field.
• A warning appears if you run it manually in a terminal. Running uvx king-crimson-mcp directly just waits silently for a client — that's normal (it speaks over stdin/stdout). You don't need to run it by hand; Claude Desktop starts and stops it for you. Press Ctrl+C to stop.
• get_editions / setlist tools return an error about a missing key. That tool's API key isn't set in your config's env block. See Step 2.
• setlist data looks incomplete for older tours. setlist.fm is user-submitted; some historical shows or songs simply aren't logged there. This is a data limitation, not a bug.

Install from PyPI

For developers — the same package as Quick start above, without the Claude Desktop config:

# run directly without installing (recommended)
uvx king-crimson-mcp

# or install as a persistent tool
pipx install king-crimson-mcp
king-crimson-mcp

Secrets (MCP_CONTACT, DISCOGS_TOKEN, SETLISTFM_API_KEY) go either in a .env file in the directory you run the command from, or directly in the Claude Desktop config's env block (see below) — either is read. .env is loaded from the current working directory, since an installed package has no project directory of its own to keep one in.

Setup from source (development)

# Python 3.10+ required (3.12 recommended)
uv venv --python 3.12
source .venv/bin/activate
uv pip install -e .

# configure secrets
cp .env.example .env
# then edit .env

.env variables:

• MCP_CONTACT — required by MusicBrainz policy; identifies your app to their API via the User-Agent header.
• DISCOGS_TOKEN — needed for get_editions (Discogs personal access token).
• SETLISTFM_API_KEY — needed for get_live_history, refresh_setlist_cache, and song_performance_history.
• KC_CACHE_DIR — optional; overrides where the setlist cache is written (see below).

Running

# quick tool check via MCP Inspector
mcp dev src/king_crimson_mcp/server.py

Run refresh_setlist_cache once first — it fetches King Crimson's full concert history (~1,200 shows, ~40 seconds) and caches it locally under $XDG_CACHE_HOME/king-crimson-mcp (or ~/.cache/king-crimson-mcp; override with KC_CACHE_DIR). After that, song_performance_history reads from the cache and returns instantly.

Register with Claude Desktop

Using the published package:

{
  "mcpServers": {
    "king-crimson": {
      "command": "uvx",
      "args": ["king-crimson-mcp"],
      "env": {
        "MCP_CONTACT": "you@example.com",
        "DISCOGS_TOKEN": "...",
        "SETLISTFM_API_KEY": "..."
      }
    }
  }
}

Or, running from a local clone instead (after uv pip install -e ., which installs the same king-crimson-mcp console script into the venv):

{
  "mcpServers": {
    "king-crimson": {
      "command": "/absolute/path/to/.venv/bin/king-crimson-mcp",
      "env": { "MCP_CONTACT": "you@example.com" }
    }
  }
}

Secrets can live in .env (in the directory the command is run from) instead of the env block — either is read.

Data sources & attribution

This project is an unofficial client with no affiliation with or endorsement from MusicBrainz, the MetaBrainz Foundation, the Internet Archive, Discogs, or setlist.fm.

• MusicBrainz — free, no API key. Requires an identifying User-Agent with contact info (rate limit: 1 req/sec). Data is largely CC0; crediting MusicBrainz in your app is good practice.
• Cover Art Archive — a joint MusicBrainz / Internet Archive project. Images are contributed by individual uploaders; follow the same attribution etiquette as MusicBrainz.
• Discogs — requires a personal access token and a unique User-Agent (60 req/min authenticated). Use is subject to the Discogs API terms of service.
• setlist.fm — requires an API key (apply at api.setlist.fm). Any display of setlist.fm data must include an attribution link to the source setlist — every performance returned by this server includes its url for exactly that purpose; surface it wherever you show the data. setlist.fm data is user-submitted, so completeness and accuracy are not guaranteed.

Limitations

• setlist.fm data is user-submitted — some shows or songs may be missing or incorrect, especially from older tours.
• The incarnation boundaries are one interpretation of King Crimson's line-up history, not an official taxonomy.
• Performer credits depend on what MusicBrainz has cataloged for a given release; sparser releases yield sparser credits.

License

MIT — see LICENSE.