src/openai_patch.ts

/*
 * This file patches OpenAI SDK types for OpenResponses spec compliance.
 *
 * The OpenAI SDK uses event type names like "response.reasoning_text.delta",
 * but the OpenResponses spec uses "response.reasoning.delta" (without "_text").
 * We maintain custom event types here to match the OpenResponses specification.
 *
 * Once the OpenAI SDK aligns with OpenResponses spec, this file can be simplified.
 */
import type {
	ResponseReasoningItem as OpenAIResponseReasoningItem,
	ResponseStreamEvent as OpenAIResponseStreamEvent,
	ResponseOutputRefusal,
	ResponseOutputText,
	ResponseContentPartAddedEvent,
	ResponseContentPartDoneEvent,
	ResponseTextDeltaEvent,
	ResponseTextDoneEvent,
} from "openai/resources/responses/responses";

import type { ChatCompletionChunk } from "openai/resources/chat/completions";

export interface ReasoningTextContent {
	type: "reasoning_text";
	text: string;
}

export type PatchedResponseReasoningItem = OpenAIResponseReasoningItem & {
	// Raw CoT returned in reasoning item (in addition to the summary)
	content: ReasoningTextContent[];
};

// Custom event types for OpenResponses spec (differs from SDK's "response.reasoning_text.*")
interface PatchedResponseReasoningDeltaEvent {
	type: "response.reasoning.delta";
	sequence_number: number;
	item_id: string;
	output_index: number;
	content_index: number;
	delta: string;
}

interface PatchedResponseReasoningDoneEvent {
	type: "response.reasoning.done";
	sequence_number: number;
	item_id: string;
	output_index: number;
	content_index: number;
	text: string;
}

export type PatchedResponseStreamEvent =
	| OpenAIResponseStreamEvent
	| PatchedResponseReasoningDeltaEvent
	| PatchedResponseReasoningDoneEvent
	| PatchedResponseContentPartAddedEvent
	| PatchedResponseContentPartDoneEvent
	| PatchedResponseOutputTextDeltaEvent
	| PatchedResponseOutputTextDoneEvent;

export type PatchedResponseContentPart = ResponseOutputText | ResponseOutputRefusal | ReasoningTextContent;

export interface PatchedResponseOutputTextDeltaEvent extends ResponseTextDeltaEvent {
	logprobs: unknown[];
}

export interface PatchedResponseOutputTextDoneEvent extends ResponseTextDoneEvent {
	logprobs: unknown[];
}

interface PatchedResponseContentPartAddedEvent {
	content_index: number;
	item_id: string;
	output_index: number;
	part: PatchedResponseContentPart;
	sequence_number: number;
	type: "response.content_part.added";
}

interface PatchedResponseContentPartDoneEvent {
	content_index: number;
	item_id: string;
	output_index: number;
	part: PatchedResponseContentPart;
	sequence_number: number;
	type: "response.content_part.done";
}

export type PatchedDeltaWithReasoning = ChatCompletionChunk.Choice.Delta & {
	reasoning?: string;
	reasoning_content?: string;
};