Chat Completions API request shape

POST /v1/chat/completions accepts the OpenAI Chat Completions request body. Kindo validates the core fields and forwards the rest verbatim, which keeps the endpoint forward-compatible with new OpenAI request fields.

Required fields

Field	Type	Notes
`model`	string	A model ID from `GET /v1/models`.
`messages`	array	Must contain at least one entry. See Messages array.

Standard fields

Field	Type	Forwarded?	Notes
`stream`	boolean	—	Consumed by the route handler to switch into SSE mode.
`temperature`	number	Yes	Sampling temperature.
`max_tokens`	integer	Yes	Max tokens to generate.
`top_p`	number	Yes	Nucleus sampling.
`frequency_penalty`	number	Yes
`presence_penalty`	number	Yes
`stop`	string \| array	Yes	Stop sequences.
`tools`	array	Yes	OpenAI tool definitions (see Tool use).
`tool_choice`	string \| object	Yes	`"auto"`, `"none"`, `"required"`, or `{type: "function", function: {name: "..."}}`.
`response_format`	object	Yes	E.g. `{type: "json_object"}` or `{type: "json_schema", ...}`.
`user`	string	Yes	End-user identifier.
`seed`	integer	Yes	Determinism hint, where the upstream model supports it.
`logprobs`	boolean / object	Yes	Forwarded to the upstream model.

Anything not listed above passes through Kindo’s schema verbatim because the validator uses passthrough(). Refer to OpenAI’s Chat Completions spec for full field semantics.

Stripped-on-ingress fields

Kindo strips these fields from the outgoing upstream request so clients can’t spoof governance metadata:

metadata
litellm_metadata
proxy_server_request

Messages array

Each message has the following shape:

Field	Required	Notes
`role`	Yes	`system`, `developer`, `user`, `assistant`, or `tool`.
`content`	No	String, array of content blocks, or `null` (for assistant messages with only `tool_calls`). Arrays are forwarded verbatim and support multimodal blocks.
`name`	No	Author name.
`tool_calls`	No	Tool calls generated by the model (present on assistant messages).
`tool_call_id`	No	Required on `role: "tool"` messages — the ID of the tool call this message is responding to.

developer is treated identically to system and matches OpenAI’s own semantics.

Kindo extension fields

/v1/chat/completions is stock OpenAI — Kindo does not accept a kindo request block on this surface. Kindo’s opt-in extensions (curated system prompt, hosted tools, stateful conversations) are available on /v1/responses; see the Chat Actions guide.

Worked example

{
  "model": "claude-sonnet-4-5-20250929",
  "messages": [
    { "role": "system", "content": "You are a concise security assistant." },
    { "role": "user", "content": "Summarize CVE-2024-3094." }
  ],
  "tools": [
    {
      "type": "function",
      "function": {
        "name": "lookup_cve",
        "description": "Fetch CVE metadata.",
        "parameters": {
          "type": "object",
          "properties": { "id": { "type": "string" } },
          "required": ["id"]
        }
      }
    }
  ],
  "tool_choice": "auto",
  "max_tokens": 512,
  "temperature": 0.2
}

This is stock OpenAI Chat Completions. Kindo accepts it identically to OpenAI’s /v1/chat/completions.