mcpcost MCP server

mcpcost

Is that MCP server alive, and what does it cost your context window?

Live board: mcpcost.ulehla.dev

mcpcost probes every remote server in the official MCP registry and records, for each one:

• whether it answers initialize and tools/list, and how fast
• the protocol version it negotiates
• whether it needs auth, and which scheme (from WWW-Authenticate)
• whether it asks for payment (HTTP 402)
• how many tools it has and how many tokens their definitions cost

mcpcost: what do your own servers cost?

npx mcpcost                     # reads Claude Code, Claude Desktop, Cursor, VS Code, Windsurf and Gemini CLI configs
npx mcpcost --config .mcp.json  # one file
npx mcpcost --budget 30000      # exit 1 when the total is above the budget, for CI
npx mcpcost --claude            # exact counts from the Anthropic count_tokens endpoint (free, needs ANTHROPIC_API_KEY)
npx mcpcost mcp                 # the same measurements as an MCP server over stdio, for your agent

It starts every configured server the way your client does, lists the tools and prints the token cost per server and in total. See packages/mcpcost.

In CI, as a GitHub Action

- uses: ondraulehla/mcpcost@v1
  with:
    config: .mcp.json   # one or more config files, one per line
    budget: 30000       # fail when the tool definitions cost more than this

The job summary gets a table with every server, its result and its cost, plus the most expensive tools. A pull request that adds a 40 000-token server fails the check. Set claude: true and put ANTHROPICAPIKEY in env for exact counts from the free counttokens endpoint; the default is the o200kbase estimate. Outputs: tokens, servers, over-budget.

The board

mcpcost.ulehla.dev is rendered on the edge from a D1 database, ships no JavaScript, and refreshes every night.

• Overview: the share of servers that answer, token cost percentiles, and a form to check any server
• Check: probes one URL live, with the same steps as the daily run; the exact token count runs in the browser
• Statistics: results by cause, token cost and tool count percentiles, the heaviest tool sets, protocol versions, auth schemes, transports, biggest publishers
• Servers: full-text search over name, title, description and host (word prefixes, so git copilot finds the GitHub Copilot servers), filters by result, protocol and transport, seven sorts, and every filter is a plain URL you can share
• Server page: status, latency, protocol, capabilities, the most expensive tools, servers with the same tool set, history, and the badge
• Hosts: the 500 biggest publishers with how many distinct tool sets they actually serve

For agents and scripts

• JSON: /api/s/.json, /api/servers.json?q=…&status=ok&sort=tokens, /api/check.json?url=…, /api/summary.json
• MCP server over Streamable HTTP, no auth: https://mcpcost.ulehla.dev/mcp with the tools lookupserver, searchservers, checkserver, registrysummary. The manifest for the registry is site/server.json.
• /llms.txt lists all of it. /tokens answers the general question: how many context tokens does an MCP server cost.

Shortened. The full README is on GitHub.