- Translate Gemini `MALFORMED_FUNCTION_CALL` responses into Claude API error payloads instead of refusal stop reasons.
- Capture translated stream errors in Gemini and Vertex executors to ensure proper error propagation, usage reporting, and state management.
Closes: #6606
- Buffer and publish observed upstream usage when apply patch transformation or translation encounters an error in Meta and xAI executors
- Add stream usage buffer helpers to report failure metrics with captured upstream token usage
Closes: #6427
- Track pending completion state in OpenAI-to-Responses translator when item output is complete and a finish reason is received
- Synthesize terminal `[DONE]` event on clean EOF when response completion is pending instead of failing the stream
Closes: #6381
- Handle apply_patch custom tool call streaming deltas and snapshots for Responses API translation
- Track and resolve step indexes, function call identities, and error states across stream events
- Propagate apply_patch tool input errors and upstream failure states in stream and non-stream responses
