MCPTrello

An MCP (Model Context Protocol) server exposing a small, curated set of Trello tools — built to let an agent read and lightly update a Trello board without hand-pasted context, and as a learning exercise in how tool descriptions shape agent behavior (see DESIGN_NOTES.md for the reasoning behind each one).

Tools

Out of scope for this v1: full CRUD, remote/OAuth auth, rate limiting, MCP resources/prompts, a cc-init command, auto-creating checklists, editing or deleting existing comments, and caching board/list names between calls.

Related MCP server: trello-mcp-server

Setup

1. Get Trello credentials

1. Go to https://trello.com/power-ups/admin and create (or select) a Power-Up to get an API key.

2. From the same key page, generate a token by following the "Token" link — this authorizes the key to act as your Trello account.

2. Configure environment

cp .env.example .env

Fill in .env:

TRELLO_API_KEY=...
TRELLO_TOKEN=...
DEFAULT_BOARD_ID=...   # optional — id of the board to use when `board` is omitted

DEFAULT_BOARD_ID is optional. Without it, tools that need a board either require you to pass one explicitly or (for search_cards) search across every board you can access.

3. Install and build

Requires Node.js 18+.

npm install
npm run build

4. Register with Claude Code

claude mcp add trello -- node <absolute-path-to-repo>\dist\index.js

Verification

• npm run build — TypeScript build; run after any source change.

• npm run verify — launches the built server as a subprocess over stdio using the MCP SDK's own Client + StdioClientTransport, lists all tools, and calls each one (including at least one error/ambiguous case per tool) against your real Trello account. Requires a fully filled-in .env — it makes real API calls.

• MCP Inspector (npx @modelcontextprotocol/inspector --cli node dist/index.js --method tools/list) is a secondary, best-effort check. Every published Inspector version requires Node ≥22.7.5; on Node 18 it will fail to start. If you want to run it, use a separate Node 22+ installation (e.g. via nvm) rather than upgrading this project's runtime requirement.