Method streamWithRetry

src/core/agent.ts:584–612

* Consume a model stream, automatically re-establishing the request up to * MAX_STREAM_RETRIES times on a transient/connection failure. A user abort is * never retried. * * Before the first chunk of an attempt nothing has streamed, so the retry is * always clean. Once chunks have streamed,

(
		makeStream: () => ReturnType<LLMClient["createMessage"]>,
		signal: AbortSignal,
		onRestart?: () => boolean,
	)

	 * propagates.
	 */
	private async *streamWithRetry(
		makeStream: () => ReturnType<LLMClient["createMessage"]>,
		signal: AbortSignal,
		onRestart?: () => boolean,
	): ReturnType<LLMClient["createMessage"]> {
		for (let attempt = 0; ; attempt++) {
			let produced = false
			try {
				for await (const chunk of makeStream()) {
					produced = true
					yield chunk
				}
				return
			} catch (error) {
				if (signal.aborted || (error as Error).name === "AbortError") throw error
				if (attempt >= MAX_STREAM_RETRIES || !isRetryableStreamError(error)) throw error
				// Output already streamed this attempt: only retry if the caller can
				// cleanly roll it back, otherwise a restart would duplicate it.
				if (produced && !(onRestart?.() ?? false)) throw error
				const delayMs = retryBackoffMs(attempt)
				this.options.callbacks.onEvent({
					type: "system",
					message: `Connection to the model failed (${(error as Error).message}). Retrying ${attempt + 1}/${MAX_STREAM_RETRIES} in ${Math.ceil(delayMs / 1000)}s…`,
					isError: false,
				})
				await interruptibleDelay(delayMs, signal)
			}
		}
	}

	/** Run one model request + tool execution round. Returns true when the turn is over. */
	private async runStep(): Promise<boolean> {