Decision ModelsDecision Models
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Migration guide

Move the endpoint. Review the differences.

Decision Models is a separate service for open-weight model alternatives. The shared state and questions structure is familiar; surrounding service behavior is different. s1-pro accepts up to three text questions per request; s1-fast and s1-vision accept one. Exceeding the model limit returns non-retryable HTTP 400 request_limit_exceeded.

  1. Use the Decision Models API base URL

    When available, the base URL is https://api.decisionmodels.io. Do not use this website as an API endpoint; API requests go to the API host.

  2. Create a Decision Models API key

    Decision Models keys, account balances, prepaid credits and model availability are separate from TypeSafe Jev.

  3. Choose a processing tier

    Use the key default or S1-Region: eu|global where the account permits it. EU requests run only on contracted operators inside the EU; inference data never leaves the EU.

  4. Check the live catalogue

    Confirm current model IDs, modalities, prices and supported question shapes from GET /v1/models.

  5. Observe each model’s question limit

    s1-pro accepts up to three text questions; s1-fast and s1-vision accept one. Exceeding the model limit returns HTTP 400 request_limit_exceeded with retryable: false; the service does not split or discard questions.

  6. Handle retries deliberately

    A request keeps only a keyed body digest, request ID, status and usage receipt for 24 hours; no answer or request content is stored for replay. While it is running, the same key and body return 202 in_progress. After settlement, or while settlement is uncertain, the same key returns 409 idempotency_replay_unavailable with a receipt and no second charge. A confirmed failure with no answer and no charge releases the key so the same key and body can retry. Reusing a key with a different body returns 409 idempotency_conflict. Use a fresh key only for a deliberately new inference.

Compatibility boundary

Shared request shape; separate service contract

Decision Models follows the shared state/questions structure, with up to three text questions for s1-pro, and one for s1-fast and s1-vision. Exceeding the model limit returns non-retryable HTTP 400 request_limit_exceeded. Score rubrics carry an ordered criteria array of at least two levels; TypeSafe’s published schema also accepts a single level, which launch requests must not use. Model IDs, tiers, auth, billing, other limits, metadata and error behavior are Decision Models-specific. Byte-for-byte compatibility is not claimed until the documented-schema integration test passes.

Jev is a trademark of TypeSafe AI. Decision Models is not affiliated with TypeSafe AI and does not resell Jev.

https://api.system1models.ai keeps working.