PR #23177 real dev runtime verification main: 32ecd71726; PR: 596fa17d70cecdf4bf23b713b9fdc5fec6e1ec58 Playwright 1.60.0 + /usr/bin/google-chrome; one isolated dev server at a time. MAIN: authenticated omitted-field export returned 204; saved spans = 0. MAIN: decoder warnings: payload.resourceSpans is not iterable; scope omitted: attributes lookup threw TypeError. PR: identical authenticated omitted-field export returned 204; span saved, status=0, events=[], links=[]. Diagnostics visibly lists it. CONTROL: populated OTLP record is deeply equal on main and PR, including IDs, times, scope, status and attributes. PR: omitted resource/scope/span lists and empty status accepted; nested event/link attributes and empty array/kvlist values normalized correctly. MAIN: real OpenTelemetry JS SDK 2.12.0 exporter span persisted. SDK emits populated defaults, so it does not reproduce the omitted-field bug. PR: real OpenTelemetry JS SDK 2.12.0 exporter span persisted. SDK emits populated defaults, so it does not reproduce the omitted-field bug. PR: no browser OTLP decode warnings. MAIN: real Codex gpt-6.1-sol app-server turn ran a command in the real repo and returned @t3tools/monorepo. PR: real Codex gpt-6.1-sol app-server turn ran a command in the real repo and returned @t3tools/monorepo. NEIGHBOR: unauthenticated POST /api/observability/v1/traces -> HTTP 401 (checked separately with curl). BLACKSMITH: check:changed passed: format, lint, knip, typecheck (28 packages), observability.test.ts (19 tests). Not verified: native desktop/mobile, macOS/Windows, external collector forwarding, other providers, relay/tunnel/multi-environment sessions.