Each request runs in one of three service tiers. The tier sets the order in which a model serves requests and the price.
| Tier | Price | When the model is busy | Use it for |
|---|---|---|---|
priority | Highest | Served first. A 503 is the least likely. | Traffic that a user waits for |
standard | Middle | Served after priority. This is the default. | Most traffic |
flex | Lowest | Served last, and refused first with a 503. | Evaluations, batch jobs, backfills |
The model, its output and zero data retention are the same in each tier. When the model has free capacity, all three tiers run at the same speed.
Choose a tier
Send the munito-service-tier header with priority, standard or flex:
curl https://api.munito.ai/inference/v1/chat/completions \
-H "Authorization: Bearer $MUNITO_API_KEY" \
-H "munito-service-tier: flex" \
-H "Content-Type: application/json" \
-d '{"model": "qwen/qwen3.8-27b", "messages": [{"role": "user", "content": "Hello"}]}'Chat Completions and Responses also accept the OpenAI service_tier field: priority, flex, or default for standard. When a request sends both, the header wins. Messages reads only the header.
The munito-service-tier response header names the tier that is billed. A chat completion also names it in the service_tier field, with default for standard.
Limits of each tier
- Priority needs a paid account. On the free tier, a priority request gets
403. - Flex gets a
503sooner than the other tiers, and overflow does not apply to it. Send flex work as a background request, so that it waits in line for capacity:Prefer: respond-asyncon Chat Completions, orbackground: trueon Responses. - A request above your rate limit can still run on spare capacity. The response then carries
x-ratelimit-over-limit: yes, and you pay the price of the tier that you asked for.