[pacocartones]

Summary

• A non-streaming Claude response only translated end_turn, tool_use and max_tokens (responseTranslator.ts, the Claude branch of translateNonStreamingResponse). refusal, model_context_window_exceeded, stop_sequence and pause_turn stayed raw.
• For an OpenAI client, sanitizeOpenAIResponse normalises them later. A Gemini client has no such step: OPENAI_TO_GEMINI_FINISH_REASON falls back to STOP, so a refusal or a context-window stop reached it as a clean STOP. Measured on e23fb0f: refusal -> STOP, model_context_window_exceeded -> STOP.
• The branch now uses normalizeOpenAICompatibleFinishReasonString, which already holds the same mapping as the streaming convertStopReason: refusal -> content_filter, max_tokens and model_context_window_exceeded -> length, stop_sequence and pause_turn -> stop. A Gemini client now gets SAFETY and MAX_TOKENS.

Related Issues

• Follow-up to fix(sse): map refusal and context-window stop reasons to OpenAI finish reasons #16453, which mapped these stop reasons on the streaming path.

Target Branch

• Base is the active release/v3.8.x branch (the highest open release/v*), not main
• New feature? From 3.8.55 on it is held with the v4-feature label for the v4 channel

Validation

• Change type: other (translator)
• Focused tests and category gates from the golden path
• npm run lint (eslint on the changed files: clean)
• Reconciled with the current active release base; focused checks rerun afterward
• Production-code changes include a new or updated automated test in this PR

Tests Added Or Updated

• tests/unit/claude-nonstream-stop-reasons.test.ts (new): 6 tests. On the base 5 fail and 1 passes; with the fix all 6 pass. One of them checks that end_turn, tool_use and max_tokens keep their mappings for both OpenAI and Gemini clients.

Coverage Notes

• The 28 test files that import responseTranslator: 375/375 pass with the fix.

Reviewer Notes

• It does not conflict with fix(translator): give Claude clients refusal and max_tokens instead of raw or clean stop reasons #16501, fix(translator): a truncated non-streaming Responses turn finishes with length for Chat clients #16507 or fix(responses): a truncated non-streaming Chat turn reaches a Responses client as incomplete #16517, which touch other functions in the same file.