agent-ecosystem/docs/research/codex-native-runtime-phase-0-signoff-evidence.md

Codex Native Runtime - Phase 0 Sign-off Evidence

Captured on 2026-04-19.

This file is the repo-visible evidence package referenced by:

• codex-native-runtime-phase-0-implementation-spec.md

Verdict

Phase 0 sign-off evidence is now captured.

What this proves:

• the codex-native lane executes through the raw codex exec --json seam
• persisted transcript projection remains parseable by current claude_team readers
• ephemeral and persistent runs keep different history-completeness truth
• thread status, warning attribution, executable identity, and usage authority survive end-to-end
• old Codex lane fallback truth remains covered by targeted regression tests

What this does not mean:

• codex-native should be unlocked for general runtime selection
• auto should start resolving to codex-native
• broader plugin or interactive capability claims are now safe

Command Package

agent_teams_orchestrator

Executed:

bun test src/services/codexNative/signOffHarness.test.ts \
  src/services/codexNative/statusAuthority.test.ts \
  src/services/codexNative/transcriptProjector.test.ts \
  src/services/codexNative/turnExecutor.test.ts \
  src/services/codexNative/execRunner.test.ts \
  src/services/codexNative/jsonlMapper.test.ts \
  src/services/runtimeBackends/codexBackendResolver.test.ts \
  src/services/runtimeBackends/registry.agentTeams.test.ts

Observed result:

• 27 pass
• 0 fail

claude_team

Executed:

pnpm exec vitest run \
  test/main/utils/jsonl.test.ts \
  test/main/services/parsing/SessionParser.test.ts \
  test/main/services/team/BoardTaskExactLogStrictParser.test.ts \
  test/main/ipc/configValidation.test.ts \
  test/main/services/runtime/ProviderConnectionService.test.ts \
  test/main/services/runtime/providerAwareCliEnv.test.ts \
  test/main/services/runtime/ClaudeMultimodelBridgeService.test.ts \
  test/renderer/components/runtime/providerConnectionUi.test.ts \
  test/renderer/components/runtime/ProviderRuntimeSettingsDialog.test.ts \
  test/renderer/components/cli/CliStatusVisibility.test.ts

Observed result:

• 134 pass
• 0 fail

Diff cleanliness

Executed:

git diff --check

Observed result:

• clean in both worktrees

Live Native Run Evidence

Common live-run facts

Observed from both runs:

• native binary path: /usr/local/bin/codex
• native binary source: system-path
• native binary version: codex-cli 0.117.0
• credential input source for the sign-off harness: OPENAI_API_KEY
• credential source observed by the runner: explicit-api-key
• capability profile: headless-limited
• final assistant text: OK

Ephemeral run

Executed:

bun run ./scripts/codex-native-phase0-signoff.ts \
  --cwd /tmp \
  --prompt 'Reply only with OK' \
  --ephemeral

Observed result:

• thread id: 019da680-6f43-7e10-824c-4d985bcdca12
• completion policy: ephemeral
• final history completeness: live-only
• final usage authority: live-turn-completed
• assistant usage:
  • input tokens: 23616
  • cached input tokens: 0
  • output tokens: 42

History authority proof:

• projected warning subtype: codex_native_warning
• projected warning source: history
• observed warning text contained:
  • thread/read failed while backfilling turn items for turn completion
  • ephemeral threads do not support includeTurns

This is the explicit proof that ephemeral live stream does not equal canonical hydrated history.

Persistent run

Executed:

bun run ./scripts/codex-native-phase0-signoff.ts \
  --cwd /tmp \
  --prompt 'Reply only with OK' \
  --persistent

Observed result:

• thread id: 019da680-6f42-77c0-94f1-4e450a69d1f1
• completion policy: persistent
• final history completeness: explicit-hydration-required
• final usage authority: live-turn-completed
• assistant usage:
  • input tokens: 23616
  • cached input tokens: 0
  • output tokens: 33

This is the explicit proof that persistent native runs keep a different history-completeness contract from ephemeral runs.

Warning Attribution Proof

The live runs produced both:

• process/runtime warnings
• history-completeness warnings

Observed process-attributed warnings included:

• plugin cache / featured plugins unauthorized warnings
• state DB migration mismatch warnings
• shell snapshot timeout warnings
• MCP process-group termination warnings

Observed history-attributed warning included:

• thread/read failed while backfilling turn items for turn completion: ... ephemeral threads do not support includeTurns

This proves the lane now keeps process and history warning truth distinct in projected transcript rows.

Thread-status Proof

Observed projected system rows included:

• codex_native_thread_status
  • running
  • completed

This proves the lane now writes native thread-status authority into persisted transcript-compatible rows instead of forcing UI and replay consumers to infer health from provider-global process truth.

Parser And Exact-log Proof

Covered by green targeted tests:

• test/main/utils/jsonl.test.ts
• test/main/services/parsing/SessionParser.test.ts
• test/main/services/team/BoardTaskExactLogStrictParser.test.ts

These tests prove:

• projected assistant usage remains parseable
• projected warning/source metadata remains parseable
• projected execution-summary/history metadata remains parseable
• exact-log readers do not drop the native authority rows

Degraded Old-lane Fallback Proof

Covered by green targeted tests:

• src/services/runtimeBackends/codexBackendResolver.test.ts
• src/services/runtimeBackends/registry.agentTeams.test.ts

Those tests prove:

• auto still does not silently resolve to codex-native
• native lane remains unavailable without:
  • feature flag
  • binary
  • CODEX_API_KEY
• old Codex lane remains the truthful fallback when native is absent or degraded

Sign-off Conclusion

✅ The Phase 0 code path is implementation-complete and evidence-backed.

⚠️ The lane should still remain:

• feature-flagged
• non-default
• non-auto-resolved
• non-selectable for normal runtime switching

That remaining lock is now a rollout-policy choice, not a missing-code problem.