For AI assistants and developers

Use 50heads from an AI assistant.

Connect 50heads to a compatible AI assistant so it can ask verified people a question and receive the result. It costs from 20 credits per answer. It works through MCP, the standard that lets an assistant use outside tools, so it runs in Claude, Cursor, ChatGPT and any host that supports MCP.

Add it to your host

Claude

In Claude, open Settings, then Connectors, and add a custom connector with this URL. You'll sign in and set a daily spend cap.

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

Claude Code

Run this in a terminal. Claude Code opens a browser for you to sign in and set a daily spend cap.

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

Cursor

Add this to ~/.cursor/mcp.json, then sign in when Cursor asks.

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

ChatGPT

In ChatGPT, open Settings, then Apps and connectors, then Advanced settings, and turn on Developer mode. Choose Create, paste this URL and pick OAuth.

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

VS Code

Add this to .vscode/mcp.json in your workspace, or run MCP: Add Server. VS Code opens the sign-in page.

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

Windsurf

Add this to ~/.codeium/windsurf/mcp_config.json, with an API key from the portal.

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

Other (npx)

For hosts that launch a local command. Needs Node 20 or later and an API key from the portal.

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

Where to find 50heads

Each of these gives your AI assistant the same tools. Use the one it supports.

Hosted server: https://mcp.50heads.com/mcp Available now. Nothing to install: add the address and sign in.
npm package: npx -y @50heads/mcp Available now, for assistants that run a local command. Needs Node 20 or later and an API key.
Official MCP Registry: com.50heads/mcp Available now. Assistants and directories that read the registry will find 50heads there.
Directories: Coming soon to the Claude, ChatGPT and Cursor directories, Smithery, Glama, PulseMCP and mcp.so. Until then, add the hosted server yourself.

The basic flow is three steps

Estimate is free and never spends. Ask reserves the credits. Wait for results: 50heads holds the wait, so your assistant makes one call instead of checking again and again.

> estimate({ action: "quote", question: { type: "single_choice", text: "Which menu would you order from tonight?",
             options: [{ label: "Menu A" }, { label: "Menu B" }], n: 50, tier: 1 } })
  20 credits × 50 = 1000 credits

> ask({ action: "ask", ...same question, idempotency_key: "4f9c…" })
  task q_8k2f · working · 0 of 50 answered

> results({ action: "get", question_id: "q_8k2f" })   # or action "wait" on older hosts
  complete · winner "Menu B" · margin 36 points · confidence high

Ask for a go or a no go

Set a line on a yes-or-no question, such as Yes above 60%. You get a verdict with a range: go, no go or unclear. The line costs nothing extra.

Available tools

estimate: Price, time and validation for a question. Never spends.
ask: Posts a question. Needs an idempotency key: retrying with the same key cannot create a second question or a second charge.
results: The results so far, single answers, files and your recent questions, so an agent can reuse a result before re-asking. Can wait on our side for the answers.
questions: Stops a live question and refunds the answers not given, adds more answers, flags a poor answer, or files a question.
projects: Projects and labels that keep questions findable.
webhooks: Webhook endpoints, their deliveries and recent events, so a script does not have to keep checking.
organization: Read-only: the organisation, its domains, SCIM, service accounts and the Slack and Zapier connections.
audit: Read-only: the organisation's audit log, listed or exported.
help: Searches the help centre and sends feedback to support.

Controls for unattended use

Every connection has a daily spend cap, 5,000 credits unless you change it. The server refuses an ask that would go over it.
Ask needs an idempotency key. Retrying with the same key cannot create a second question or a second charge.
Questions pass the same content rules as everyone else's. A refused question costs nothing.
Results never identify a head.

Your data is not training data

We don't use your questions, the answers you buy or the reasons heads write to train AI models, and we don't sell them. AI and your data

Or call the API

Everything the MCP server does is a plain HTTPS call. Keys start fh_live_ and are shown once.

curl https://api.50heads.com/v1/billing/estimate \
  -H "Content-Type: application/json" \
  -d '{"draft":{"type":"single_choice","text":"Which menu would you order from tonight?",
       "options":[{"label":"Menu A"},{"label":"Menu B"}],"n":50,"tier":1}}'

curl https://api.50heads.com/v2/questions \
  -H "Authorization: Bearer $FIFTYHEADS_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{"draft":{"type":"single_choice","text":"Which menu would you order from tonight?",
       "options":[{"label":"Menu A"},{"label":"Menu B"}],"n":50,"tier":1,"language":"en"}}'

curl "https://api.50heads.com/v2/questions/q_8k2f/wait?seconds=25" \
  -H "Authorization: Bearer $FIFTYHEADS_API_KEY"

Use 50heads from Zapier

No code needed. In Zapier you can ask a question, add heads, cancel, and get results with the go or no-go verdict. Zaps can also start when a question finishes. Zapier connects with OAuth like any other app, with the same scopes and daily cap.

Zapier in the developer docs

Let your AI assistant ask verified people.

API docs MCP setup Webhooks