fix(bedrock): throw APIError for error events delivered in chunk frames#1021
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When a Bedrock response stream wraps an Anthropic-format error payload
({"type":"error","error":{...}}) inside a chunk frame, the iterator now
throws an APIError instead of yielding the payload to MessageStream,
which would otherwise fail with "Unexpected event order, got error
before message_start" and discard the underlying error.
Closes #387
Refs anthropics/anthropic-sdk-python#1472
cameron-mcateer
approved these changes
Apr 30, 2026
felixfbecker
approved these changes
Apr 30, 2026
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When a Bedrock response stream delivers an Anthropic-format error payload (
{"type":"error","error":{...}}) inside achunkevent-stream frame, the iterator previously yielded it as a regular message event. Downstream,MessageStream.#accumulateMessagewould then throwUnexpected event order, got error before "message_start"— discarding the underlying error type and message.This change detects
type: "error"in chunk payloads and throwsAPIErrorwith the error type preserved (matching the base SDK SSE handling), so consumers see the actual error and retry logic can engage.Adds
tests/streaming.test.tsexercising the fullde_ResponseStream→ iterator path with real event-stream encoding.Closes #387
Refs anthropics/anthropic-sdk-python#1472 (same issue, Python SDK)