Function chatStream

packages/openai-base/src/adapters/responses-text.ts:64–166

(
    options: TextOptions<TProviderOptions>,
  )

  }

  async *chatStream(
    options: TextOptions<TProviderOptions>,
  ): AsyncIterable<StreamChunk> {
    // Track tool call metadata by unique ID
    // Responses API streams tool calls with deltas — first chunk has ID/name,
    // subsequent chunks only have args.
    // We assign our own indices as we encounter unique tool call IDs.
    const toolCallMetadata = new Map<
      string,
      {
        index: number
        name: string
        started: boolean
        // Set once TOOL_CALL_END has been emitted (via args.done or the
        // output_item.done backfill) so the two paths don't double-emit.
        ended?: boolean
        // Set when args.done arrives before TOOL_CALL_START could fire
        // (output_item.added lacked a name). output_item.done picks these
        // up to emit the missing END. Allow explicit `undefined` so the
        // emission paths can re-clear the slot after handing it off.
        pendingArguments?: string
      }
    >()

    // AG-UI lifecycle tracking
    const aguiState = {
      runId: generateId(this.name),
      threadId: options.threadId ?? generateId(this.name),
      messageId: generateId(this.name),
      hasEmittedRunStarted: false,
    }

    try {
      // mapOptionsToRequest can throw on caller-side validation failures
      // (empty user content, unsupported parts, webSearchTool() rejection in
      // the OpenRouter override). Keep it inside the try so those failures
      // surface as RUN_ERROR events instead of iterator throws.
      const requestParams = this.mapOptionsToRequest(options)
      options.logger.request(
        `activity=chat provider=${this.name} model=${this.model} messages=${options.messages.length} tools=${options.tools?.length ?? 0} stream=true`,
        { provider: this.name, model: this.model },
      )
      const response = await this.client.responses.create(
        {
          ...requestParams,
          stream: true,
        },
        extractRequestOptions(options.request),
      )

      yield* this.processStreamChunks(
        response,
        toolCallMetadata,
        options,
        aguiState,
      )
    } catch (error: unknown) {
      // Narrow before logging: raw SDK errors can carry request metadata