WordPress Trac MCP server

A read-only Model Context Protocol server for the WordPress.org Trac instances, starting with WordPress Core Trac. It runs as a Cloudflare Worker and uses Trac's public HTML, CSV, RSS, and diff endpoints.

Live servers:

Production:

• Standard MCP: https://wordpress-trac-mcp-server-prod.a8c-aiops.workers.dev/mcp
• Search/fetch compatibility: https://wordpress-trac-mcp-server-prod.a8c-aiops.workers.dev/mcp/chatgpt
• Health check: https://wordpress-trac-mcp-server-prod.a8c-aiops.workers.dev/health

Staging:

• Standard MCP: https://mcp-server-wporg-trac-staging.a8c-aiops.workers.dev/mcp
• Search/fetch compatibility: https://mcp-server-wporg-trac-staging.a8c-aiops.workers.dev/mcp/chatgpt
• Health check: https://mcp-server-wporg-trac-staging.a8c-aiops.workers.dev/health

The former staging deployment at https://mcp-server-wporg-trac-staging.a8cai.workers.dev is deprecated and runs older code. Its a8cai.workers.dev subdomain differs from the active staging deployment's a8c-aiops.workers.dev subdomain.

Trac instances

Each Trac instance has its own endpoint. /mcp and /mcp/chatgpt serve Core.

Trac	Standard MCP	Search/fetch compatibility
WordPress Core	/mcp	/mcp/chatgpt
Making WordPress.org	/mcp/meta	/mcp/meta/chatgpt
Themes	/mcp/themes	/mcp/themes/chatgpt
Plugins	/mcp/plugins	/mcp/plugins/chatgpt
bbPress	/mcp/bbpress	/mcp/bbpress/chatgpt
BuddyPress	/mcp/buddypress	/mcp/buddypress/chatgpt
GlotPress	/mcp/glotpress	/mcp/glotpress/chatgpt
Google Summer of Code	/mcp/gsoc	/mcp/gsoc/chatgpt

The table is a discovery aid rather than an allowlist. Any <slug>.trac.wordpress.org resolves at /mcp/<slug>, so a Trac added later needs no change here. An instance is bound to the connection rather than chosen per tool call, so a client cannot read the wrong Trac by mistake.

Instances configure different fields. Themes has no components, and only some instances have severities. getTracInfo reports a field the instance does not configure as unavailable instead of failing. Ticket fields behave the same way: focuses exists only on Core and comes back empty elsewhere.

Filtering is stricter, because Trac answers a filter on a field it does not configure with the unfiltered result set rather than an error, and that reads as a real match count. searchTickets rejects such a filter and names the fields the instance does have. This covers both the separate arguments and the expressions inside query.

Connect to one instance per client entry. Use several entries to read several Tracs.

Tools

The standard /mcp endpoint provides:

Tool	Purpose
searchTickets	Search by keywords, ticket number, or structured filters
getTicket	Read a ticket, its attachments, changesets, recent human discussion, and linked pull requests
getChangeset	Read a changeset and an optional truncated diff
getTimeline	Read recent Trac activity
getTracInfo	List components, milestones, priorities, severities, types, or statuses

getChangeset expects the numeric revision argument, not rev:

{
  "revision": 58504,
  "includeDiff": false
}

The /mcp/chatgpt compatibility endpoint provides search and fetch. Use a bare number for a ticket and an r prefix for a changeset: 65739 and r58504.

No tool takes a Trac instance argument. The endpoint you connect to decides which Trac the tools read.

Search filters

searchTickets accepts plain keywords, ticket numbers, or filter expressions joined with &:

{
  "query": "milestone=6.9&status=closed&resolution=fixed",
  "limit": 50,
  "page": 2
}

It also accepts status, component, milestone, and resolution as separate arguments. A separate argument overrides the same field in query. Results include pagination metadata.

Tool errors

A failed tool call returns an MCP result with isError: true. Its JSON payload carries a machine-readable code alongside the human-readable error message. not_found errors also name the resource and id that were requested:

{
  "code": "not_found",
  "error": "Ticket 99999999 not found",
  "resource": "ticket",
  "id": 99999999
}

code	Meaning
not_found	The requested ticket or changeset does not exist
invalid_argument	An argument passed schema validation but cannot be used, such as an unsupported search filter field
rate_limited	Trac throttled the request and bounded retries did not clear it
upstream_error	Trac or a supporting service failed or returned unexpected content

Codes are stable API surface: branch on code, never on error wording. An existing code keeps its meaning and is only removed or renamed with a major version bump, while messages can change freely. New codes may be added over time, so treat an unrecognized code as upstream_error.

Arguments that fail schema validation are rejected earlier with a JSON-RPC -32602 invalid-params error and do not produce a tool error result.

Connect

Remote-capable MCP clients can connect directly to the standard endpoint. Clients that need a local bridge can use mcp-remote:

{
  "mcpServers": {
    "wordpress-trac": {
      "command": "npx",
      "args": [
        "mcp-remote",
        "https://wordpress-trac-mcp-server-prod.a8c-aiops.workers.dev/mcp"
      ]
    },
    "wordpress-meta-trac": {
      "command": "npx",
      "args": [
        "mcp-remote",
        "https://wordpress-trac-mcp-server-prod.a8c-aiops.workers.dev/mcp/meta"
      ]
    }
  }
}

For ChatGPT, add the compatibility endpoint as a custom app. See OpenAI's current MCP help because product labels and setup steps change.

After changing a configured server URL, reconnect the MCP server or restart the client once. Future deployments to the same URL do not require a client configuration change.

Develop

Requirements: Node.js 22 or later and pnpm 10.

pnpm install
pnpm dev

Open http://localhost:8787/ to view the local landing page. See docs/local-development.md for the full browser-preview workflow and troubleshooting.

Run the complete local quality gate:

pnpm check

This runs TypeScript, Biome, Vitest, and a Cloudflare Worker dry-run build. See docs/testing.md for manual protocol and live-data checks.

Deployment requires a configured Cloudflare account:

# Staging
pnpm run deploy

# Production
pnpm run deploy:production

Design and safety

• The server is read-only and has no Trac credentials.
• Tool inputs receive runtime validation before any upstream request.
• Upstream requests stay on *.trac.wordpress.org and the official linked-PR endpoint on api.wordpress.org. The instance slug comes from the URL path, is validated against a strict pattern before it reaches a request, and every request is checked against the resolved origin.
• Upstream redirects are never followed. *.trac.wordpress.org has wildcard DNS and redirects unknown subdomains to Core, so following one would answer for one instance with another's data. A redirect that leaves the instance origin is reported as an unknown instance; one that stays on it is reported as an upstream failure.
• Transient transport failures, rate limits, server errors, and Trac bot challenges receive bounded retries. Permanent 403 and 404 responses return immediately.
• Responses are parsed from public Trac pages and machine-readable formats.
• The Worker keeps no ticket cache or durable state.

Contribute

Keep tool schemas, runtime validation, tests, and documentation aligned. Run pnpm check before opening a pull request.

License

GPL-2.0-or-later.