- Gate MetaExecutor signature sanitization by baseURL so custom/third-party meta-api-key endpoints replay router-suffixed Meta Muse envelopes while native api.meta.ai stays native-only
- Pass resolved target model (with requested-model fallback for aliased deployments) through Codex, Codex WebSocket, and OpenAI-compat Responses sanitization paths
- Broaden Meta Muse model-id boundary matching (muse, meta/muse, muse_*, meta-muse-*) and allow Meta envelopes in the Codex reasoning replay cache
- Reuse CodexReplaySignatureForTarget in Claude-to-Codex request translation and avoid duplicating streamed thought summaries on Interactions reasoning done events
- Filter `response.subscription_usage` events and associated metadata across Meta streaming and non-streaming executors.
- Ensure subscription telemetry is stripped from OpenAI Responses SSE streams and WebSocket forwarders.
- Track delivery of terminal response events in Meta stream execution.
- Prevent client cancellation errors from being marked as API failures if the terminal event was already delivered.
- Add unit tests for Meta stream client disconnection behavior before and after terminal events.
Closes: #6688
- 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
- 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
- Introduced `MetaExecutor` to support native Meta (Muse Code) API operations, including `Execute`, `ExecuteStream`, and `CountTokens`.
- Added logic to handle Meta-specific `responses` endpoint, including request preparation, enriched authentication, header management, and response translation.
- Implemented token counting functionality with custom `CountTokens` logic.
- Updated `meta_executor` to process streamed and non-streamed responses, maintaining compatibility with the Codex schema.
- Added utility functions to handle events, errors, and enriched metadata common to Meta API requests.
- Extended `models.json` to include Meta's updated configuration with additional thinking levels like "minimal" and "max."
- Introduced comprehensive tests to validate Meta-specific execution, streaming, header assignments, and response formatting.
