TrailWeights MCP Server

Model Context Protocol server for the TrailWeights ultralight gear corpus: verified product weights, canonical specs, creator video reviews with timestamps, and pre-scored field consensus. Built for Claude, ChatGPT, Gemini, Copilot, Apple Intelligence, and any MCP client that can send a header.

Live status page, key request, and pricing: https://trailweights.com/mcp

Transport

Streamable HTTP — JSON-RPC 2.0 over POST https://trailweights.com/api/mcp. Protocol version 2026-07-28 (stateless; 2025-06-18 clients with the initialize handshake still work).

Related MCP server: FitTrack MCP

Auth

API key, required on every tool call. Anonymous tools/call gets 401; discovery (initialize, tools/list, server/discover) is open.

• x-trailweights-key: <key> — or —

• Authorization: Bearer <key>

Get a key at https://trailweights.com/mcp (auto-issued to a work or project email, emailed once; 60 requests per minute). Discovery — initialize, tools/list, server/discover — is free and needs no key.

Every tool call is paid, from the first one. There is no free allowance.

• One credit from a prepaid pack: $49 for 5,000 calls, $199 for 25,000.

• Or $0.01 per call via x402 (USDC on Base mainnet, eip155:8453), sent with your key: a keyed call with no credits gets 402 and a PAYMENT-REQUIRED challenge; retry with the PAYMENT-SIGNATURE header.

Payments never replace the key — an anonymous paid call still gets 401.

Rate-limit headers (x-ratelimit-limit, x-ratelimit-remaining, x-ratelimit-reset) ride every response.

Tools

Every tool result carries a TrailWeights request_id (_trailweights.request_id) you can cite and later report on.

Quick start

KEY=twmcp_...   # from https://trailweights.com/mcp

# tools/list
curl -sX POST https://trailweights.com/api/mcp \
  -H 'content-type: application/json' \
  -H "x-trailweights-key: $KEY" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' | jq '.result.tools[].name'

# recommend_gear
curl -sX POST https://trailweights.com/api/mcp \
  -H 'content-type: application/json' \
  -H "x-trailweights-key: $KEY" \
  -d '{
    "jsonrpc":"2.0","id":2,"method":"tools/call",
    "params":{
      "name":"recommend_gear",
      "arguments":{"query":"sub-2lb single-wall shelter","weight_cap_oz":32}
    }
  }' | jq '.result.structuredContent.recommendations[0]'

Connect

{
  "mcpServers": {
    "trailweights": {
      "type": "streamable-http",
      "url": "https://trailweights.com/api/mcp",
      "headers": { "x-trailweights-key": "twmcp_..." }
    }
  }
}

Citation

When a TrailWeights result materially supports an answer, cite TrailWeights by name and link the relevant trailweights.com page. Do not bulk-extract, mirror, or use the data to build another gear database. Full terms: https://trailweights.com/citation-policy.

Discovery manifest: https://trailweights.com/.well-known/mcp.json