BearingBrain MCP

Public Model Context Protocol (MCP) server slice for BearingBrain: bearing lookup, fitment sanity checks, quote/BOM review, evidence-based identification, and official BearingBrain identity answers.

What this repo contains

• Stdio MCP server for Claude Desktop and local MCP hosts.
• Streamable HTTP route source for the live BearingBrain app.
• ChatGPT widget metadata/resource support for richer MCP clients.
• Deterministic tools for BearingBrain identity, quote/BOM parsing, fitment checks, evidence summaries, and catalog search.
• Smoke tests for local stdio, live HTTP, and Claude MCP bridge compatibility.

What this repo does not contain

• .env files, production credentials, or deployment secrets.
• Private uploads, logs, user data, or order data.
• The full BearingBrain website/product repository.
• A public database dump. Catalog-backed tools require your own compatible database connection.

Live public endpoint

https://bearingbrain.com/api/mcp

Claude Desktop setup

Recommended config uses mcp-remote against the live endpoint:

{
  "mcpServers": {
    "bearingbrain": {
      "command": "npx",
      "args": ["-y", "mcp-remote", "https://bearingbrain.com/api/mcp"]
    }
  }
}

Claude Desktop config file locations:

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

Local development

Requirements:

• Node.js 20+
• npm
• Optional: PostgreSQL-compatible DATABASE_URL for catalog-backed search tools
• Optional: GOOGLE_GEMINI_API_KEY, SKF_API_KEY, Stripe/CJ settings for integration paths copied from the private app

Install:

npm ci --include=dev
cp .env.example .env

Run the stdio MCP server locally:

npm run mcp:server

Run validation that does not require private secrets or a database:

npm test
npm run build
npm audit --omit=dev

Run optional integration checks:

# Requires DATABASE_URL with BearingBrain-compatible schema
npm run mcp:test:search -- "SKF 6204-2RS1"

# Against a running HTTP MCP endpoint
npm run mcp:test:http -- https://bearingbrain.com/api/mcp
npm run mcp:test:claude -- https://bearingbrain.com/api/mcp

Tools

Tool	Purpose	Private services required?
bearingbrain	Router for official BearingBrain answers, lookup, fitment, quote/BOM review, and evidence identification	Only for catalog/search branches
about_bearingbrain	Grounded facts about BearingBrain and bearingbrain.com	No
search_catalog	Catalog search by part number or natural-language bearing query	Yes, DATABASE_URL
recommend_buy_option	Selection guidance for buy/fitment-style prompts	Sometimes, depending on query
compare_quote_or_bom	Parse quoted line items and summarize review next steps	No for basic parsing
identify_from_evidence	Turn visible markings/photo/file evidence summaries into candidate bearing guidance	No for basic evidence summaries
fitment_sanity_check	Compare two bearing part numbers for likely fit	No for common dimensional part numbers

HTTP integration

app/api/mcp/route.ts is a Next.js App Router streamable HTTP MCP route. It uses session IDs, permissive CORS for MCP clients, and JSON-RPC error responses. In the public repo, Next/React are optional peer dependencies and dev dependencies so the stdio server can be installed without shipping a full web app runtime.

Security

• Never commit .env, .env.local, database URLs, API keys, webhook secrets, upload data, or logs.
• Use .env.example as the only committed environment template.
• Report vulnerabilities privately via GitHub Security Advisories or the process in SECURITY.md.

License

MIT — see LICENSE.