otel: support gen_ai.response.time_to_first_chunk in sqlite store#312938
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The CLI runtime is migrating from the vendor-prefixed github.copilot.time_to_first_chunk attribute to the OTel GenAI semconv attribute gen_ai.response.time_to_first_chunk. Both encode TTFT in seconds. The sqlite store's _ttftMs() now reads either name (preferring the new one) so we keep populating ttft_ms before, during, and after the runtime rollout. Adds two unit tests: one for the new attribute alone, one verifying the new attribute wins when both are present. Refs: open-telemetry/semantic-conventions#3607 github/copilot-agent-runtime#6949
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dmitrivMS
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Summary
The CLI agent runtime is migrating from the vendor-prefixed attribute
github.copilot.time_to_first_chunkto the new OTel GenAI semantic-conventions attributegen_ai.response.time_to_first_chunk. Both encode time-to-first-chunk in seconds. To stay green before, during, and after the runtime rollout, the OTel sqlite store's_ttftMs()now reads either attribute (preferring the new one) when denormalizing TTFT into thettft_mscolumn.Changes
extensions/copilot/src/platform/otel/node/sqlite/otelSqliteStore.ts—_ttftMs()checksgen_ai.response.time_to_first_chunkfirst, falls back togithub.copilot.time_to_first_chunk.extensions/copilot/src/platform/otel/node/sqlite/test/otelSqliteStore.spec.ts— Adds two unit tests:ttft_ms(ms).gen_ai.request.stream(the other new attribute in the upstream PR) has no current consumer here, so no shim is needed — it flows through as a normal span attribute.Verification
References