Request Body
Request Body Parameters
Reference for the /v1/chat/completions POST body.
| Parameter | Type | Required | Default | Description |
|---|---|---|---|---|
model | string | YES | - | Model ID. Call GET /v1/models for available options. |
messages | object[] | YES | - | Conversation messages. Each has role (system/user/assistant/tool), content (string), optional name (a-z, A-Z, 0-9, dashes, underscores, max 64). |
thinking | object|null | No | null | Object with type: "enabled" or "disabled". At UMVA, default is disabled. |
reasoning_effort | string | No | "high" | Values: "high", "max". "low"/"medium" map to "high", "xhigh" maps to "max". |
max_tokens | int|null | No | model default | Max tokens to generate. |
response_format | object|null | No | {"type":"text"} | Output format: "text" or "json_object". For JSON, instruct model via system/user message. |
stop | string|string[]|null | No | null | Up to 16 stop sequences. |
stream | bool|null | No | false | If true, SSE streaming. Terminated by data: [DONE]. |
stream_options | object|null | No | null | Use {"include_usage":true} for token usage before [DONE]. |
temperature | number|null | No | 1 | Sampling 0-2. Higher=random, lower=deterministic. Alter this or top_p. |
top_p | number|null | No | 1 | Nucleus sampling. 0.1 = top 10% mass. Alter this or temperature. |
tools | object[]|null | No | null | Function calling tools. Only "function" type. Each has name, description, parameters (JSON Schema). Max 128. |
tool_choice | string|object|null | No | "none"/"auto" | "none" (no tools), "auto" (model decides), "required" (must call), or object to force a specific tool. |
logprobs | bool|null | No | false | Return log probabilities of output tokens. |
top_logprobs | int|null | No | null | 0-20. Most likely tokens per position. Requires logprobs: true. |
user_id | string | No | null | Custom identifier. Chars: [a-zA-Z0-9\-_], max 512. For content safety, KVCache isolation. |
Deprecated Parameters
frequency_penalty and presence_penalty are no longer supported. Passing them has no effect.