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These guides take one task at a time and walk it through end to end: the request to send, the response to read, the limits that apply, and what to do when a call is refused. Read them once you have made a first call with the quickstart and want to build a real integration against https://api.opentype.dev. Every example sends a key from the OPENTYPE_API_KEY environment variable. Create one on the API keys page of the console.

Decision runs

Ask typed questions about a JSON state and get a probability for every answer, in one call to Neon 1.1.

Decision runs

Every request field, the response, stages, costs, and the limits that shape a question set.

Yes/no questions (noul)

Read P(yes) and turn it into an action with thresholds you choose.

Choice questions

Pick one of 2 to 20 named options, with a probability for each.

Score questions

Rate on an ordered scale and read the expected level.

Conditional questions

Order questions with depends_on and ask them only when ask_if holds.

Verdict runs

The schema-validated JSON contract, and why Neon 1.1 does not serve it today.

Model Router

Pick the best model for a prompt from a benchmark catalog, with Neon 1.1 classifying the task.

Model Router

Send a task, choose a policy and filters, and read the ranked shortlist.

Task types and policies

The 27 task types, their families, and the benchmarks each one is ranked on.

Reliable requests

Send runs that survive timeouts, retries and restarts without paying twice.

Idempotency

The required Idempotency-Key header, replays, and when to mint a new key.

Error handling

Branch on code, decide what to retry, and log the request_id.

Polling

Recover a run you lost track of with GET /v1/runs/{run_id}.

Streaming

Observe a run’s stored state over server-sent events.

Pagination

Walk the run list with limit and offset, and size usage ledger reads.

Spend and billing

Pay for runs with prepaid credit and keep track of where it goes.

Credits and billing

How credit is bought, held for a run, and drawn down.

Auto-recharge

Top up automatically when the balance falls below a threshold.

Handling insufficient credits

What a 402 insufficient_credits means and how to recover.

Usage reporting

Totals, the per-call ledger, and one run’s cost.

Spend limits and quotas

The per-request ceiling and the period quotas that refuse with 429.

Go to production

Prepare keys and code for real traffic.

Key rotation

Rotate a key and roll the new secret out to your services.

Production checklist

What to check before real traffic reaches OpenType.

Code examples

Ready-to-adapt requests in curl, TypeScript and Python.
  • Quickstart - make a first decision run before you start on a guide.
  • Decision questions - the concepts behind noul, choice and score questions.
  • Errors - every error code the API returns and what it means.
  • API reference - the full request and response contract for every route.