50heads

50heads MCP

Ask fifty verified people a five-second question from Claude, ChatGPT, Cursor or your own agent, and see what they think. 50 answers at Tier 1: 1000 credits, priced in your account's currency.

There are two ways in, with the same tools:

• Hosted (recommended): https://mcp.50heads.com/mcp. Streamable HTTP, sign in with OAuth in the browser. Nothing to install.
• Local: npx -y @50heads/mcp, a stdio server for hosts that launch a command. Needs Node 20 or later and an API key (or a one-time login).

Install

Pick your host below. The hosted server needs nothing installed: add the URL and sign in with OAuth in the browser, which also sets the connection's daily spend cap. The local server (npx -y @50heads/mcp) needs Node 20 or later and an API key.

Make an API key, if you need one, on the Developers page of the dashboard: https://50heads.com/app/developers. Keys start fh_live_ and are shown once. Or run npx -y @50heads/mcp login once and leave the key out.

npx -y @50heads/mcp config [host] prints any of these. The same instructions are on https://50heads.com/en-us/docs/mcp.

Claude (claude.ai and Claude Desktop)

Hosted, sign in with OAuth. Settings, Connectors, Add custom connector. Paste the URL and sign in when asked. On Team and Enterprise plans an owner adds it for the organization first.

https://mcp.50heads.com/mcp

Or with an API key, in claude_desktop_config.json (macOS: ~/Library/Application Support/Claude/, Windows: %APPDATA%\Claude\).

{

"mcpServers": { "50heads": { "command": "npx", "args": [ "-y", "@50heads/mcp" ], "env": { "FIFTYHEADS_API_KEY": "fh_live_…" } } } }

Claude Code

Hosted, sign in with OAuth. Run in a terminal, then /mcp in Claude Code to sign in.

claude mcp add --transport http 50heads https://mcp.50heads.com/mcp

Or with an API key (CI and scripts):

claude mcp add --transport http 50heads https://mcp.50heads.com/mcp --header "Authorization: Bearer fh_live_…"

Cursor

Hosted, sign in with OAuth. ~/.cursor/mcp.json (or .cursor/mcp.json in a project). Cursor opens the sign-in page.

{

"mcpServers": { "50heads": { "url": "https://mcp.50heads.com/mcp" } } }

Or with an API key:

{

"mcpServers": { "50heads": { "url": "https://mcp.50heads.com/mcp", "headers": { "Authorization": "Bearer fh_live_…" } } } }

ChatGPT

Hosted, sign in with OAuth. Settings, Apps and Connectors, Advanced settings, turn on Developer mode, then Create. Paste the URL and choose OAuth. On Business and Enterprise plans an admin turns on Developer mode first.

https://mcp.50heads.com/mcp

VS Code

Hosted, sign in with OAuth. .vscode/mcp.json in the workspace, or MCP: Add Server from the command palette.

{

"servers": { "50heads": { "type": "http", "url": "https://mcp.50heads.com/mcp" } } }

Or from a terminal:

code --add-mcp '{"name":"50heads","type":"http","url":"https://mcp.50heads.com/mcp"}'

Windsurf

Local, with an API key. ~/.codeium/windsurf/mcp_config.json, or Windsurf Settings, Cascade, MCP servers, View raw config.

{

"mcpServers": { "50heads": { "command": "npx", "args": [ "-y", "@50heads/mcp" ], "env": { "FIFTYHEADS_API_KEY": "fh_live_…" } } } }

Or the hosted server with an API key:

{

"mcpServers": { "50heads": { "serverUrl": "https://mcp.50heads.com/mcp", "headers": { "Authorization": "Bearer fh_live_…" } } } }

Any other host

Local, with an API key. Hosts that launch a local command. Needs Node 20 or later and an API key from the dashboard.

FIFTYHEADS_API_KEY=fh_live_… npx -y @50heads/mcp

Hosts that speak Streamable HTTP: https://mcp.50heads.com/mcp with the header "Authorization: Bearer fh_live_…", or OAuth.

{

"mcpServers": { "50heads": { "url": "https://mcp.50heads.com/mcp", "headers": { "Authorization": "Bearer fh_live_…" } } } }

Check it works

Ask your host to "use 50heads to estimate asking fifty people which of two names they prefer". estimate (action quote) is free and never spends credits. In Claude Code, /mcp lists the server and its tools; elsewhere, look for 50heads in the host's tools or connectors list.

Signing in on the command line

npx -y @50heads/mcp login     # opens the browser; the token goes in your keychain

npx -y @50heads/mcp status npx -y @50heads/mcp logout

login uses the OAuth device flow against https://auth.50heads.com. Tokens are kept in the macOS Keychain or the Secret Service on Linux, else in ~/.config/50heads/credentials.json (mode 600). An API key in FIFTYHEADS_API_KEY wins when both are present.

--proxy forwards stdio to the hosted server instead of running the tools locally.

Tools (9, each takes an action)

There are nine tools, never more than ten. Each tool takes an action and that action's own arguments, validated per action (the input is a discriminated union on action), and tools/list documents every action in the tool's description. Scopes belong to actions, not tools: a connection that lacks the scope for an action is refused with insufficient_scope for that action alone, and a read-only grant never reaches an action that changes something. Tool annotations are true of every action in the tool: estimate, results, organization and audit are read-only (readOnlyHint: true); questions, projects and webhooks each hold a cancel or delete, so they carry destructiveHint: true; ask and help change something but destroy nothing. Each tool's _meta["com.50heads/scopes"] lists the scope of each action.

Actions and scopes

| webhooks | events | `webh