> For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://docs.nvidia.com/nemo/relay/v0.5.0/reference/api/rust-library-reference/nemo-relay/codec/openai_responses/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.nvidia.com/nemo/relay/_mcp/server. # Module openai_responses > Built-in codec for the OpenAI Responses API. Generated from `cargo doc --no-deps -p nemo-relay -p nemo-relay-adaptive -p nemo-relay-pii-redaction -p nemo-relay-ffi -p nemo-relay-types -p nemo-relay-plugin -p nemo-relay-worker-proto -p nemo-relay-worker`. Built-in codec for the OpenAI Responses API. Implements [`LlmCodec`](/reference/api/rust-library-reference/nemo-relay/codec/traits/trait-llmcodec) (request decode/encode) and [`LlmResponseCodec`](/reference/api/rust-library-reference/nemo-relay/codec/traits/trait-llmresponsecodec) (response decode) for the OpenAI Responses API format. The Responses API differs significantly from Chat Completions: * **Response**: Heterogeneous `output` array (message, function\_call, reasoning) instead of `choices[0].message`. * **Finish reason**: Derived from `status` + `incomplete_details.reason` instead of `finish_reason` field. * **Request**: Uses `input` (string or array) instead of `messages`, and `instructions` (top-level) instead of system message. * **Max tokens**: `max_output_tokens` instead of `max_tokens`. ## Structs * [OpenAIResponsesCodec](/reference/api/rust-library-reference/nemo-relay/codec/openai_responses/struct-openairesponsescodec): Built-in codec for the OpenAI Responses API. * [OpenAIResponsesStreamingCodec](/reference/api/rust-library-reference/nemo-relay/codec/openai_responses/struct-openairesponsesstreamingcodec): Streaming counterpart to [`OpenAIResponsesCodec`](/reference/api/rust-library-reference/nemo-relay/codec/openai_responses/struct-openairesponsescodec). > Built-in codec for the OpenAI Responses API. ## Docs - [Struct OpenAI Responses Codec](https://docs.nvidia.com/nemo/relay/v0.5.0/reference/api/rust-library-reference/nemo-relay/codec/openai_responses/struct-openairesponsescodec.md): Built-in codec for the OpenAI Responses API. - [Struct OpenAI Responses Streaming Codec](https://docs.nvidia.com/nemo/relay/v0.5.0/reference/api/rust-library-reference/nemo-relay/codec/openai_responses/struct-openairesponsesstreamingcodec.md): Streaming counterpart to `OpenAIResponsesCodec`.