Function convertToOpenAiMessages

src/api/transform/openai-format.ts:322–597

(
	anthropicMessages: Anthropic.Messages.MessageParam[],
	options?: ConvertToOpenAiMessagesOptions,
)

}

export function convertToOpenAiMessages(
	anthropicMessages: Anthropic.Messages.MessageParam[],
	options?: ConvertToOpenAiMessagesOptions,
): OpenAI.Chat.ChatCompletionMessageParam[] {
	const openAiMessages: OpenAI.Chat.ChatCompletionMessageParam[] = []

	const mapReasoningDetails = (details: unknown): any[] | undefined => {
		if (!Array.isArray(details)) {
			return undefined
		}

		return details.map((detail: any) => {
			// Strip `id` from openai-responses-v1 blocks because OpenAI's Responses API
			// requires `store: true` to persist reasoning blocks. Since we manage
			// conversation state client-side, we don't use `store: true`, and sending
			// back the `id` field causes a 404 error.
			if (detail?.format === "openai-responses-v1" && detail?.id) {
				const { id, ...rest } = detail
				return rest
			}
			return detail
		})
	}

	// Use provided normalization function or identity function
	const normalizeId = options?.normalizeToolCallId ?? ((id: string) => id)

	for (const anthropicMessage of anthropicMessages) {
		if (typeof anthropicMessage.content === "string") {
			// Some upstream transforms (e.g. [`Task.buildCleanConversationHistory()`](src/core/task/Task.ts:4048))
			// will convert a single text block into a string for compactness.
			// If a message also contains reasoning_details (Gemini 3 / xAI / o-series, etc.),
			// we must preserve it here as well.
			const messageWithDetails = anthropicMessage as AssistantMessageWithReasoning
			const baseMessage: OpenAI.Chat.ChatCompletionMessageParam & ReasoningPassthroughFields = {
				role: anthropicMessage.role,
				content: anthropicMessage.content,
			}

			if (anthropicMessage.role === "assistant") {
				const mapped = mapReasoningDetails(messageWithDetails.reasoning_details)
				if (mapped) {
					baseMessage.reasoning_details = mapped
				}
				// Pass through reasoning_content for DeepSeek / Z.ai thinking mode.
				if (typeof messageWithDetails.reasoning_content === "string" && messageWithDetails.reasoning_content) {
					baseMessage.reasoning_content = messageWithDetails.reasoning_content
				}
			}

			openAiMessages.push(baseMessage)
		} else {
			// image_url.url is base64 encoded image data
			// ensure it contains the content-type of the image: data:image/png;base64,
			/*
        { role: "user", content: "" | { type: "text", text: string } | { type: "image_url", image_url: { url: string } } },
         // content required unless tool_calls is present
        { role: "assistant", content?: "" | null, tool_calls?: [{ id: "", function: { name: "", arguments: "" }, type: "function" }] },