> ## Documentation Index > Fetch the complete documentation index at: https://developers.meshapi.ai/llms.txt > Use this file to discover all available pages before exploring further. # Make a structured decision > Get a typed answer with a calibrated probability, instead of prose to parse. Send your application `state` plus named `questions`. Each question declares its own `type`: `choice` picks one of your options and reports a probability for each, `score` rates against an ordered scale, and `noul` returns a single probability. `noul` is a **probability in [0, 1]**, not a true/false — despite the name. The answers come back keyed by your own question names. This endpoint is **beta**: it rides an upstream path we do not control, so the contract may change. ## OpenAPI ````yaml /api/openapi.json post /v1/evaluate openapi: 3.1.0 info: title: MeshAPI description: One key, all AI models. version: 0.1.0 servers: - url: https://api.meshapi.ai security: - BearerAuth: [] paths: /v1/evaluate: post: tags: - Evaluate summary: Make a structured decision description: >- Get a typed answer with a calibrated probability, instead of prose to parse. Send your application `state` plus named `questions`. Each question declares its own `type`: `choice` picks one of your options and reports a probability for each, `score` rates against an ordered scale, and `noul` returns a single probability. `noul` is a **probability in [0, 1]**, not a true/false — despite the name. The answers come back keyed by your own question names. This endpoint is **beta**: it rides an upstream path we do not control, so the contract may change. operationId: create_evaluation parameters: - in: header name: X-Mesh-Version required: false schema: type: string enum: - 2026-08 - 2026-09 default: 2026-08 example: 2026-09 description: >- Dated version of the API contract to pin this request to. Omit it and the request is served under `2026-08` — the oldest supported version, so an existing integration is never moved by a release. A malformed or unsupported value is rejected with `400 invalid_api_version` rather than falling back silently. The version actually served is echoed as `X-Mesh-Version` on every response, including errors. requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/EvaluateRequest' responses: '200': description: Typed answers, one per question content: application/json: schema: $ref: '#/components/schemas/EvaluateResponse' example: id: eval_2f9c4a1b8d3e5f7a6c0b9d2e model: typesafe/jev-1.13 answers: department: type: choice choice: billing probabilities: billing: 1 technical: 0 confidence: 1 urgency: type: score score: 1.3 legend: '0': Can wait a week '1': Within a day '2': Immediately probabilities: '0': 0.01 '1': 0.68 '2': 0.31 confidence: 0.53 needs_human: type: noul noul: 0.8 usage: input_tokens: 396 output_tokens: 64 total_tokens: 460 '400': description: The model does not exist, or cannot serve this request '401': description: Missing or invalid API key '402': description: Insufficient credits '403': description: API key is suspended, or lacks the evaluate:write scope '422': description: Request validation failed '429': description: Rate limit exceeded (RPM or RPD) '500': description: Mesh-internal error — do not retry '503': description: Upstream provider error, or credentials not configured '504': description: Upstream provider did not respond in time security: - BearerAuth: [] components: schemas: EvaluateRequest: properties: model: type: string title: Model description: Which model decides. Use an id from GET /v1/models. state: anyOf: - type: string - additionalProperties: true type: object - items: {} type: array title: State description: >- The application state to judge — free text, or any JSON object or array. Every question is answered against this same state. questions: patternProperties: ^[A-Za-z0-9_-]{1,64}$: oneOf: - $ref: '#/components/schemas/NoulQuestion' - $ref: '#/components/schemas/ChoiceQuestion' - $ref: '#/components/schemas/ScoreQuestion' discriminator: propertyName: type mapping: choice: '#/components/schemas/ChoiceQuestion' noul: '#/components/schemas/NoulQuestion' score: '#/components/schemas/ScoreQuestion' type: object minProperties: 1 title: Questions description: >- The questions to answer, keyed by your own name for each. Those names are the keys of the answers you get back. tags: anyOf: - additionalProperties: type: string type: object - type: 'null' title: Tags description: >- Your own labels for this request, echoed back on the usage row and available as a filter and a group-by dimension in the usage API. String keys to string values. Never put personal or sensitive data here — tags are stored with the usage record and are not redacted. examples: - env: prod feature: summariser safety_identifier: anyOf: - type: string maxLength: 256 - type: 'null' title: Safety Identifier description: >- A stable, anonymised identifier for the end user making this request, recorded on the usage row and available as a filter and a group-by dimension in the usage API. Supersedes the deprecated `user` field. Use an opaque id, not an email address or a name. additionalProperties: false type: object required: - model - state - questions title: EvaluateRequest description: Request body for ``POST /v1/evaluate``. example: model: typesafe/jev-1.13 questions: department: criteria: billing: Payments, refunds and invoices technical: Bugs, outages and integration problems instructions: Which team should handle this ticket? type: choice needs_human: instructions: Probability that this needs a human reply. type: noul urgency: criteria: - Can wait a week - Within a day - Immediately instructions: How urgently does this need a reply? type: score state: plan: pro subject: Refund for order 4821 never arrived EvaluateResponse: properties: id: type: string title: Id description: This evaluation's id, `eval_` followed by 24 hex. model: type: string title: Model description: The model id you asked for, not the provider's. answers: patternProperties: ^[A-Za-z0-9_-]{1,64}$: oneOf: - $ref: '#/components/schemas/ChoiceAnswer' - $ref: '#/components/schemas/ScoreAnswer' - $ref: '#/components/schemas/NoulAnswer' discriminator: propertyName: type mapping: choice: '#/components/schemas/ChoiceAnswer' noul: '#/components/schemas/NoulAnswer' score: '#/components/schemas/ScoreAnswer' type: object title: Answers description: One answer per question, keyed by the names you sent. usage: anyOf: - $ref: '#/components/schemas/EvaluateUsage' - type: 'null' type: object required: - id - model - answers title: EvaluateResponse description: Response body for ``POST /v1/evaluate``. EvaluateUsage: properties: input_tokens: anyOf: - type: integer - type: 'null' title: Input Tokens output_tokens: anyOf: - type: integer - type: 'null' title: Output Tokens total_tokens: anyOf: - type: integer - type: 'null' title: Total Tokens type: object title: EvaluateUsage description: Tokens as the provider reported them — what the request is billed on. securitySchemes: BearerAuth: type: http scheme: bearer description: >- Enter your MeshAPI key (`rsk_...`) or, for the admin-keys endpoints, a dashboard session token — sent as `Authorization: Bearer `. ````