TuringCorp — MCP server
A decision model for the calls that don't have a right answer. Your agent has two defensible options and has to pick one. Send both: a panel of models judges them together and returns the better one, how far apart it judged them (a calibrated confidence), and why.
- Endpoint (canonical):
https://mcp.turingcorp.net/mcp - Aliases:
https://mcp.turingcorp.net/andhttps://mcp.turingcorp.net/mcp/ - Health:
https://mcp.turingcorp.net/healthz - Transport: Streamable HTTP, stateless (no session, no Durable Object).
GET /mcp→ 405 is normal. - Protocol: MCP
2026-07-28(modern) and2025-06-18(legacy) — one route serves both. - Discovery methods (
server/discover,tools/list) need no credentials — directory scanners can read the full tool list unauthenticated, by design.
Making a decision: decide
| In | task (string), optionA (string), optionB (string) — all required |
| Out | job_id (string), betterOption ("option_A" | "option_B"), confidence (percentage string, e.g. "76.7%"), reason (string) |
| Annotations | readOnlyHint: true · openWorldHint: false · idempotentHint: false |
| Timeout | Reserve 180–300 seconds — a decision is a long call. The timeout is a client/host setting, not a tool parameter: there is nothing to pass in the call. A 60s default cuts it off before the answer arrives; if that happens, do not call again — retrieve by job_id. |
| Long calls | A client that declares the io.modelcontextprotocol/tasks extension gets a task handle back instead of holding one connection open for minutes, and polls tasks/get — see Retrieving a result. Clients that do not declare it see no change at all. |
A successful call returns the decision inline. job_id, betterOption, confidence and reason all arrivein the same tool result — there is nothing to poll and nothing to fetch afterwards. The job_id is only for thecase where the call never came back (timeout, dropped connection, client gave up waiting).
confidence is this service's own judgement of how far apart the two options were — a reference for your decision-making, not an instruction, not a result, and not a prediction of how the choice turns out. As a rough reading: ≥90% clearly apart · 80–90% apart, less clearly · 70–80% a closer call · <70% close to evenly matched. These ranges are descriptive only. Choose your own threshold for your own use case; for high-stakes or irreversible decisions apply your own review policy. Observed accuracy for each range, and how it was measured, is published at https://api.turingcorp.net — that page is the authority on the bands and their measured accuracy.
⚠️ idempotentHint: false is an honest declaration: a retried call is a new call. Record the job_id the result returns — a decision you have already paid for can be collected for 7 days with the same credential (GET https://api.turingcorp.net/v1/jobs?job_id=<id>; without the id, GET https://api.turingcorp.net/v1/jobs lists the job ids for that credential). Retrieve instead of retrying.
When not to use it
- More than two options. It compares exactly A and B — there is no third slot, and it will not rank a list.
- Anything you can compute or verify. A spec, a test, a price, a document: if something objective decides it, use that. This is for choices where no objective rule does.
- Factual questions. It picks between two candidates; it does not look anything up.
- Speed-critical paths. A decision is a long call and a paid one. Do not put it behind a request that has to answer in seconds.
- High-stakes irreversible calls without review. Route on the confidence and keep your own review policy.
How to fill the three arguments
task— state the decision neutrally, without leaning toward either side: "Which email do I send?", not "Should I send the honest one?"optionA/optionB— one concrete option each, plus the case for it. Plain text or Markdown, any length; keep the two sides roughly comparable so the comparison is fair.- One option = one plan. Do not bundle alternatives into a single side ("go indoors or postpone"): it compares the two slots, it does not split one of them for you.
{
"task": "Which version of the delivery-slip email do I send to a client we want to keep?",
"optionA": "Short and direct: the integration took longer than planned, delivery moves to the 24th, everything else is unchanged.",
"optionB": "Warmer and longer: thank them for the kickoff, explain that dependencies took more time, offer to walk through the details."
}
More patterns — choosing the version you send, thresholding on the confidence, and writing the two options sothe comparison is fair: docs/COOKBOOK.md.
Retrieving a result
Every call returns a job_id. A call that is allowed to finish returns the decision inline — the job_id is onlyfor the case where it never came back.
⚠️ How to retrieve — use get_result. Retrieval needs the Agent Pass, and inside an MCP host the agentusually does not have it — so retrieval is a tool call, not a REST call: get_result is authenticated by thehost, which attaches the pass for you. An agent never handles the pass, and the credential is deliberately not atool argument (it would end up in prompts and transcripts).
get_resultwith ajob_id— that job's status, and once it succeeded, the same decision body the originalcall returned.get_resultwith no argument — the job ids this credential created in the last 7 days. This is the case thatmatters most: when a call is cut off, you never received an id.- Read-only and free — it starts no new work and costs nothing, so it is safe to retry(
readOnlyHint: true,idempotentHint: true). - A host that declares the
io.modelcontextprotocol/tasksextension can polltasks/getinstead. Most clients donot declare it yet, which is whyget_resultexists.
Operator/host, with the pass (the same data over REST):
- With the id —
GET https://api.turingcorp.net/v1/jobs?job_id=<id>using the same Agent Pass. - Without it —
GET https://api.turingcorp.net/v1/jobslists the job ids that credential created in the last 7days; then fetch one as above. The list carries only the job id, the product and a timestamp. - Nothing yet — an empty list is not an error, and there is no
job_id=0placeholder:{"object":"list","window_seconds":604800,"data":[]}. Asking for0returns404 No such job.
Retrieval returns the job's status and, once it succeeded, the same body the call itself would have returned. A jobthat is not yours, or older than 7 days, is reported as unavailable. GET https://api.turingcorp.net/v1/accountreturns {"account_id":"…"}.
The practical answer is not to need retrieval: reserve 180–300 seconds so the call is allowed to finish.
See it decide first
There is no free tier, so we publish the evidence instead: 27 real decisions, recorded verbatim — the question, both options, which one was preferred, the confidence reported, and the reason. Nine domains, three cases each: Writing · Tech · Business · Research · Career · Money · People · Travel · Everyday.
→ https://github.com/TuringCorp-net/poe-demo-public — dataset: examples.json
Read the confidence column first. On ordinary, closely matched questions it reports 70–90%, not 99% — and that is the point of a calibrated number rather than a decorative one: a high value means the comparison was decisive and the pick can be acted on, a low value means the two options really are close and the choice stays yours. In this set the range is 27.3%–88.3%, median 74.0%, none above 90%, because these are everyday close calls, not easy ones. What the bands deliver when they are decisive is published at https://api.turingcorp.net.
Authentication
Send an Agent Pass: Authorization: Bearer <pass>.
Issued at https://agent-pass.turingcorp.net — self-service signup (email verification) → top up → get a pass. A pass is valid for 7 days and can be re-rolled. If a call is refused as an invalid credential, sign in there again and re-roll.
Errors fall into two classes, and they arrive in different places:
Credential problems are rejected before the call (HTTP 401 +
WWW-Authenticate). Business failures come back as a tool result withisError: trueplus a JSON block{error, http_status, action_url, message}—http_statusis the upstream status; the tool call itself is HTTP 200.
| Class | What comes back | Examples |
|---|---|---|
| Credential | HTTP 401 + WWW-Authenticate — no tool result is produced |
no credential · expired or invalid pass (invalid_credential, with a re-login URL in the message) |
| Business | HTTP 200, tool result isError: true, plus a JSON block |
insufficient balance (http_status 402, action_url pointing at top-up) · over quota (http_status 429) |
Branch on the HTTP status first: a 401 will not succeed on retry without a new credential, whereas a business failure was a call that ran and was declined — read the block for the reason and the next step. The detailed contract is under Errors are machine-readable below.
Entry rate limit: 120 requests / 60 s / client IP. This is flood damping, not a quota — the real per-key quota is enforced separately. The counter is approximate: it is maintained per edge location and is eventually consistent, so a brief overshoot is possible.
Two ways in — and they are not the same
- Through an MCP client or host (Claude Code, Cursor, VS Code, Codex, TRAE, Coze…). The host holds the credential and attaches it for you: you do not set an
Authorizationheader yourself, and in most hosts you cannot. The timeout is a host setting, not something you pass in the call. - Directly against the REST API (https://api.turingcorp.net). Here you do send
Authorization: Bearer <Agent Pass>yourself, and you can retrieve a job by id.
⚠️ The part that catches people out: being able to call the tool through a host does not mean you can reach theREST API. The host may never hand you the underlying Agent Pass, so a job-retrieval call you make on your own cancome back 401. If your host declares the Tasks extension, retrieve through the tool surface instead (seeRetrieving a result); if it does not, retrieval may simply not be reachable from where you are.
Quickstart
You need an Agent Pass to call the tool. Discovery (tools/list) works without one — calling decide does not.
🔑 Where the pass lives matters. If your client can keep it out of the file, do that — VS Code's${input:…}, Codex's bearer_token_env_var. A pass written in plain text inside mcp.json or any client configis readable by every agent and process that can read that file, and assistants do read their own config — onecan print your pass straight into its output. Treat a client config as public within your machine.
1. Get an Agent Pass
Self-service at https://agent-pass.turingcorp.net: sign up with an email address, verify it, add credit. The pass is shown once; it is valid for 7 days and can be re-rolled at any time. Agents can do the same thing over the API — see that site's /llms.txt.
2. Point your client at the endpoint
Any client that reads a JSON config — Cursor, Windsurf, Claude Desktop:
{
"mcpServers": {
"TuringCorp": {
"type": "http",
"url": "https://mcp.turingcorp.net/mcp",
"headers": { "Authorization": "Bearer <your Agent Pass>" }
}
}
}
Keep the "type": "http" line: a client that reads a url entry with no type treats it as a local stdioserver and skips it.
Cline needs a different type — "streamableHttp" (camelCase, no hyphen). Anything else, or omitting it,makes Cline fall back to SSE, which this server does not speak, and the connection fails with 405. Thesettings file is cline_mcp_settings.json (MCP Servers icon → Configure tab → Configure MCP Servers):
{
"mcpServers": {
"TuringCorp": {
"type": "streamableHttp",
"url": "https://mcp.turingcorp.net/mcp",
"headers": { "Authorization": "Bearer <your Agent Pass>" },
"disabled": false,
"autoApprove": [],
"timeout": 300
}
}
}
timeout is in seconds — leave it at 300 or higher. Cline has had a bug(#2296, closed 2025-06-23) where requests died after about a minuteregardless of that setting; if a call is cut off at ~60 s, suspect that rather than the server, and retrieve byjob_id instead of retrying (a retry is a second paid call).
A client that only speaks stdio needs a bridge, and the credential must go in through --header —mcp-remote does not read an AUTHORIZATION environment variable, so a config that only sets one connects,lists tools, and then fails on the first call with 401. The missing space after Authorization: is deliberate:some clients mangle spaces inside args.
{
"mcpServers": {
"TuringCorp": {
"command": "npx",
"args": ["-y", "mcp-remote", "https://mcp.turingcorp.net/mcp",
"--header", "Authorization:${AGENT_PASS}"],
"env": { "AGENT_PASS": "Bearer <your Agent Pass>" }
}
}
}
⚠️ A bare
npx -y mcp-remote@latest https://mcp.turingcorp.net/mcpwith no credential will connect and list tools, then fail on the first call with 401. That is expected — discovery is open, execution is not.
Claude Code:
claude mcp add --transport http TuringCorp https://mcp.turingcorp.net/mcp \
--header "Authorization: Bearer <your Agent Pass>"
3. Sanity-check it yourself
Discovery — no credentials needed:
curl -s -X POST https://mcp.turingcorp.net/mcp \
-H 'content-type: application/json' \
-H 'accept: application/json, text/event-stream' \
-H 'mcp-protocol-version: 2026-07-28' \
-H 'mcp-method: tools/list' \
--data '{"jsonrpc":"2.0","id":1,"method":"tools/list","params":{"_meta":{"io.modelcontextprotocol/protocolVersion":"2026-07-28","io.modelcontextprotocol/clientCapabilities":{}}}}'
Calling the tool additionally needs mcp-name: decide and the credential:
curl -s -X POST https://mcp.turingcorp.net/mcp \
-H 'content-type: application/json' \
-H 'accept: application/json, text/event-stream' \
-H 'mcp-protocol-version: 2026-07-28' \
-H 'mcp-method: tools/call' \
-H 'mcp-name: decide' \
-H "authorization: Bearer $AGENT_PASS" \
--data '{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"decide","arguments":{"task":"Pick a launch date","optionA":"Ship now","optionB":"Wait two weeks"},"_meta":{"io.modelcontextprotocol/protocolVersion":"2026-07-28","io.modelcontextprotocol/clientCapabilities":{}}}}'
Versions
Two version numbers exist and they are not meant to match:
| meaning | |
|---|---|
Registry version (server.json) |
the listing version - the metadata record (endpoint, auth declaration, icon, links). Advances when the listing changes. |
serverInfo.version (from the live endpoint) |
the runtime version of the deployed server. Advances when behavior changes. |
A listing-only change (for example a corrected link) advances the registry version withouttouching the runtime, so the two can legitimately differ.
Protocol details worth knowing
Acceptmust contain bothapplication/jsonandtext/event-stream, or you get 406.- Protocol versions: one route serves both generations.
- Modern
2026-07-28— noinitializehandshake; useserver/discoverand_meta. - Legacy — standard
initializehandshake. Measured negotiation: a client asking for2025-11-25,2025-06-18, or2025-03-26is answered with exactly the version it asked for; a modern2026-07-28initialize(which is not part of that generation) is answered with2025-11-25. - Server capability discovery via
tools/listandserver/discoverneeds no credentials.
- Modern
- Errors are machine-readable. There are two distinct kinds, and they arrive differently — so branch on the right thing:
| What failed | How you see it | What to branch on |
|---|---|---|
| Credential missing or invalid | HTTP 401 with a WWW-Authenticate challenge (carrying error="invalid_token" and resource_metadata); the body is a standard JSON-RPC error with error.code = -32001. No tool result is produced. |
the HTTP status code |
| Business failure — insufficient balance, quota, upstream error | a normal tool result (isError: true) whose second content block is a single JSON object you can JSON.parse, e.g. {"error":"insufficient_balance","http_status":"402","action_url":"…","message":"…"} |
the error field inside that block |
In short: credential problems are rejected before the tool runs, so they never appear as a tool result; everything else that fails after that does, with a machine-readable block attached.
- Authorization discovery:
401responses carry aresource_metadatapointing at/.well-known/oauth-protected-resource. Note that this server uses a static bearer credential, not OAuth — that document says so explicitly rather than sending you into an OAuth flow that does not exist.
Not for browser clients
This endpoint deliberately does not serve browser-based (cross-origin) MCP clients: requests carrying a browser Origin header other than localhost are rejected with 403, and no CORS headers are returned. Browser tooling such as the MCP Inspector works by proxying through a local process, which sends no Origin — that path works normally. If you need a browser page to reach this server, run a proxy you control rather than calling it cross-origin.
What this is not
- No other tiers. Other TuringCorp capabilities are not reachable through this endpoint.
- No SLA. No availability commitment is offered, and none should be inferred.
- Not an autopilot. Decider is a component you call. How you gate on it — thresholds, human review, retries — is your policy and stays yours.
decidehas no idempotency key — record the job id instead. A retried decision is a new paid call; collect the original withget_result.
Use it from a coding agent: the Agent Skill
There is an Agent Skill for coding agents (Claude Code, Codex, and anything thatreads the same skill convention). It teaches an agent when a two-option judgement is the right tool, how towrite the two options so the comparison is fair, and how to read the confidence without over-reading it.
Install it by pointing your agent at this repository, or copy skills/decider/ into your skills directory andadd the MCP server to your client (see Quickstart).
About this repository
This repository carries the discovery metadata for the server above — what directory services and clients read to find and describe it.
server.json— the official MCP Registry manifestdocs/DIRECTORIES.md— where this server is listed, and what each directory requiresdocs/COOKBOOK.md— worked patterns for handingdecidethe right kind of callskills/decider/— the Agent Skill
This server is also listed on Smithery: https://smithery.ai/servers/turingcorp/mcp
The server itself is a hosted remote endpoint; nothing here needs to be installed or run.
License
See LICENSE.