II.
ModelTransportProtocol overview
Reference · livemodel-transport:openai-chat-completions
OpenAI Chat Completions overview
Inspect the raw attributes, linked wiki pages, and inbound or outbound graph edges for model-transport:openai-chat-completions.
Attributes
displayName
OpenAI Chat Completions
vendor
OpenAI
specUrl
streamingFraming
sse
toolUseSchema
Tool calls appear in the assistant message's `tool_calls` array with
`id`, `type: "function"`, and `function: { name, arguments }`. Tool
results are submitted as messages with `role: "tool"` and
`tool_call_id` referencing the original call.
thinkingChannel
none
cacheControl
implicit
firstSpecVersion
2023-06-13
currentSpecVersion
2024-10-01
status
standard
requestBodyShape
POST /v1/chat/completions
JSON body (top-level fields):
- `model` (required, string)
- `messages` (required, array of `{role: "system"|"user"|"assistant"|"tool", content, name?, tool_call_id?, tool_calls?}`)
- `tools` (optional, array of `{type: "function", function: {name, description, parameters}}`)
- `tool_choice` (optional, "auto"|"none"|"required"|`{type:"function", function:{name}}`)
- `temperature`, `top_p`, `n`, `stop`, `max_tokens`, `max_completion_tokens` (optional)
- `stream` (optional, bool)
- `stream_options` (optional, `{include_usage: bool}`)
- `response_format` (optional, json_schema / json_object / text)
- `prompt_cache_key` (optional, string)
- `user` (optional, string — abuse-monitoring tag)
responseBodyShape
Non-streaming response (HTTP 200 application/json):
{
"id": "chatcmpl-...",
"object": "chat.completion",
"created": int,
"model": "...",
"choices": [
{ "index": 0,
"message": { "role": "assistant", "content": string|null,
"tool_calls"?: [...], "refusal"?: string|null },
"finish_reason": "stop"|"length"|"tool_calls"|"content_filter" }
],
"usage": {
"prompt_tokens": int, "completion_tokens": int, "total_tokens": int,
"prompt_tokens_details": { "cached_tokens": int },
"completion_tokens_details": { "reasoning_tokens"?: int }
}
}
streamingEventTypes
- chat.completion.chunk
- [DONE]
toolCallWireFormat
On the assistant message:
"tool_calls": [
{ "id": "call_...",
"type": "function",
"function": { "name": "<tool_name>", "arguments": "<JSON-encoded string>" } }
]
toolResultWireFormat
A subsequent message with role=tool:
{ "role": "tool",
"tool_call_id": "call_...",
"content": "<string>" }
errorEnvelope
Non-2xx response, `application/json`:
{ "error": { "type": string, "code": string|null, "message": string,
"param": string|null } }
Same envelope as the Responses API.
cacheControlWireFormat
Implicit automatic prompt caching for prompts >= 1024 tokens; cache
state reported in `usage.prompt_tokens_details.cached_tokens`.
Optional explicit scoping via top-level `prompt_cache_key`.
rateLimitSignaling
Same as OpenAI Responses: `x-ratelimit-{limit,remaining,reset}-{requests,tokens}`
headers on every response; `retry-after` on HTTP 429.
reasoningWireFormat
No first-class reasoning channel on Chat Completions. For reasoning
models served via this surface, internal reasoning tokens are
surfaced only as a count in `usage.completion_tokens_details.reasoning_tokens`;
the reasoning text itself is not returned. Use the Responses API for
reasoning summaries / encrypted reasoning state.
authHeaderFormat
`Authorization: Bearer <OPENAI_API_KEY>`
Optional: `OpenAI-Organization`, `OpenAI-Project`.
versioningHeader
No general API version header; surface version is implied by the
`/v1/chat/completions` path.
Outgoing edges
realizes1
- layer:3-transport·LayerTransport
served_by1
- provider:openai·ModelProviderProductOpenAI
spoken_by1
- model:gpt-5@current·ModelVersionGPT-5
Incoming edges
alias_of1
- model-transport:openai-compat·ModelTransportProtocolOpenAI-compatible chat completions
speaks15
- agent-core-impl:a5c.core@current·AgentCoreImpla5c Unified Core (current) — unified agent loop
- agent-core-impl:codex-sdk.core@current·AgentCoreImplCodex SDK Core (current)
- agent-core-impl:langgraph.core@current·AgentCoreImplLangGraph Graph Core (current)
- agent-core-impl:qwen.core@current·AgentCoreImplQwen Code Core (current)
- model:gpt-4o-mini@current·ModelVersionGPT-4o Mini
- model:gpt-4o@current·ModelVersionGPT-4o
- model:gpt-5-mini@current·ModelVersionGPT-5 Mini
- model:gpt-5.4-mini@current·ModelVersionGPT-5.4 Mini
- model:gpt-5.4-nano@current·ModelVersionGPT-5.4 Nano
- model:gpt-5.4@current·ModelVersionGPT-5.4
- model:gpt-5.5-pro@current·ModelVersionGPT-5.5 Pro
- model:gpt-5.5@current·ModelVersionGPT-5.5
- model:gpt-5@current·ModelVersionGPT-5
- model:o1@current·ModelVersiono1
- model:o3@current·ModelVersiono3