fix(server): keep events during thread subscription startup by t3dotgg · Pull Request #9521 · pingdotgg/t3code

t3dotgg · 2026-09-04T00:04:34Z

A thread can lose its first live events while the initial snapshot or replay starts. A missed assistant-text event can leave an empty reply until the client reloads, even though the server saved the text.

Start the thread's live consumer immediately before reading state, as the shell subscription already does.

The existing snapshot test now publishes without a delay and waits for the synchronization marker. It fails before the fix and passes after it. Eleven focused subscription/coalescer tests and the server typecheck pass. Targeted lint reports only existing unused-parameter warnings in the test file.

Created with GPT-6 Astra (preview) in Codex.

Note

Medium Risk
Changes real-time orchestration WebSocket delivery during subscription startup; incorrect behavior could still drop or reorder early thread events for clients.

Overview
Fixes a race where thread WebSocket subscriptions could drop the first live events while the initial snapshot or replay was still loading—matching behavior subscribeShell already had via startImmediately: true on the scoped fork that feeds the live event coalescer.

The integration test no longer relies on a publish delay or TestClock.withLive; it publishes as soon as the snapshot hook runs, enables requestCompletionMarker, and reads until a synchronized frame so snapshot, event, and completion are all asserted.

^{Reviewed by Cursor Bugbot for commit f4642cf. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Start live-event consumer immediately in `ws.subscribeThread` subscription handler

The scoped fork that consumes the live thread-event stream now starts immediately, so live delivery is attached before the handler proceeds with snapshot or catch-up processing. This prevents events from being missed between the fork and snapshot/replay.
Updates the subscription test in server.test.ts to request a synchronization marker, collect items up to that marker, and assert the sequence contains snapshot, event, and synchronized items.

^{Macroscope summarized f4642cf.}

github-actions · 2026-09-04T00:07:42Z

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.7 KiB	13.8 KiB	+10 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+5 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.7 KiB	6.7 KiB	+5 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.5 KiB	58.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.5 KiB	−75 B (−0.5%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	−71 B (−1.1%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.9 KiB	57.8 KiB	−88 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	8	−2 (−20.0%)	21	✅

Baseline: f8a14b2 · PR result: f4642cf · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

Codex decoded thread snapshot: 113.8 KiB
Claude decoded thread snapshot: 114.5 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

macroscopeapp · 2026-09-04T00:08:36Z

Approvability

Verdict: Approved at f4642cf

Macroscope's review found this PR approvable — This is a narrowly scoped server bug fix that starts the existing thread event consumer before snapshot or replay loading, preventing early events from being lost. The accompanying test deterministically verifies snapshot, event, and synchronization delivery without changing production interfaces or defaults.

^{You can add or adjust custom eligibility rules. Learn more.}

t3dotgg · 2026-09-04T00:04:34Z

A thread can lose its first live events while the initial snapshot or replay starts. A missed assistant-text event can leave an empty reply until the client reloads, even though the server saved the text.

Start the thread's live consumer immediately before reading state, as the shell subscription already does.

The existing snapshot test now publishes without a delay and waits for the synchronization marker. It fails before the fix and passes after it. Eleven focused subscription/coalescer tests and the server typecheck pass. Targeted lint reports only existing unused-parameter warnings in the test file.

Created with GPT-6 Astra (preview) in Codex.

Note

Medium Risk
Changes real-time orchestration WebSocket delivery during subscription startup; incorrect behavior could still drop or reorder early thread events for clients.

Overview
Fixes a race where thread WebSocket subscriptions could drop the first live events while the initial snapshot or replay was still loading—matching behavior subscribeShell already had via startImmediately: true on the scoped fork that feeds the live event coalescer.

The integration test no longer relies on a publish delay or TestClock.withLive; it publishes as soon as the snapshot hook runs, enables requestCompletionMarker, and reads until a synchronized frame so snapshot, event, and completion are all asserted.

^{Reviewed by Cursor Bugbot for commit f4642cf. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Start live-event consumer immediately in `ws.subscribeThread` subscription handler

The scoped fork that consumes the live thread-event stream now starts immediately, so live delivery is attached before the handler proceeds with snapshot or catch-up processing. This prevents events from being missed between the fork and snapshot/replay.
Updates the subscription test in server.test.ts to request a synchronization marker, collect items up to that marker, and assert the sequence contains snapshot, event, and synchronized items.

^{Macroscope summarized f4642cf.}

github-actions · 2026-09-04T00:07:42Z

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.7 KiB	13.8 KiB	+10 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+5 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.7 KiB	6.7 KiB	+5 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.5 KiB	58.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.5 KiB	−75 B (−0.5%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	−71 B (−1.1%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.9 KiB	57.8 KiB	−88 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	8	−2 (−20.0%)	21	✅

Baseline: f8a14b2 · PR result: f4642cf · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

Codex decoded thread snapshot: 113.8 KiB
Claude decoded thread snapshot: 114.5 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

macroscopeapp · 2026-09-04T00:08:36Z

Approvability

Verdict: Approved at f4642cf

Macroscope's review found this PR approvable — This is a narrowly scoped server bug fix that starts the existing thread event consumer before snapshot or replay loading, preventing early events from being lost. The accompanying test deterministically verifies snapshot, event, and synchronization delivery without changing production interfaces or defaults.

^{You can add or adjust custom eligibility rules. Learn more.}

t3dotgg · 2026-09-04T00:04:34Z

A thread can lose its first live events while the initial snapshot or replay starts. A missed assistant-text event can leave an empty reply until the client reloads, even though the server saved the text.

Start the thread's live consumer immediately before reading state, as the shell subscription already does.

The existing snapshot test now publishes without a delay and waits for the synchronization marker. It fails before the fix and passes after it. Eleven focused subscription/coalescer tests and the server typecheck pass. Targeted lint reports only existing unused-parameter warnings in the test file.

Created with GPT-6 Astra (preview) in Codex.

Note

Medium Risk
Changes real-time orchestration WebSocket delivery during subscription startup; incorrect behavior could still drop or reorder early thread events for clients.

Overview
Fixes a race where thread WebSocket subscriptions could drop the first live events while the initial snapshot or replay was still loading—matching behavior subscribeShell already had via startImmediately: true on the scoped fork that feeds the live event coalescer.

The integration test no longer relies on a publish delay or TestClock.withLive; it publishes as soon as the snapshot hook runs, enables requestCompletionMarker, and reads until a synchronized frame so snapshot, event, and completion are all asserted.

^{Reviewed by Cursor Bugbot for commit f4642cf. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Start live-event consumer immediately in `ws.subscribeThread` subscription handler

The scoped fork that consumes the live thread-event stream now starts immediately, so live delivery is attached before the handler proceeds with snapshot or catch-up processing. This prevents events from being missed between the fork and snapshot/replay.
Updates the subscription test in server.test.ts to request a synchronization marker, collect items up to that marker, and assert the sequence contains snapshot, event, and synchronized items.

^{Macroscope summarized f4642cf.}

github-actions · 2026-09-04T00:07:42Z

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.7 KiB	13.8 KiB	+10 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+5 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.7 KiB	6.7 KiB	+5 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.5 KiB	58.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.5 KiB	−75 B (−0.5%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	−71 B (−1.1%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.9 KiB	57.8 KiB	−88 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	8	−2 (−20.0%)	21	✅

Baseline: f8a14b2 · PR result: f4642cf · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

Codex decoded thread snapshot: 113.8 KiB
Claude decoded thread snapshot: 114.5 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

macroscopeapp · 2026-09-04T00:08:36Z

Approvability

Verdict: Approved at f4642cf

Macroscope's review found this PR approvable — This is a narrowly scoped server bug fix that starts the existing thread event consumer before snapshot or replay loading, preventing early events from being lost. The accompanying test deterministically verifies snapshot, event, and synchronization delivery without changing production interfaces or defaults.

^{You can add or adjust custom eligibility rules. Learn more.}

t3dotgg · 2026-09-04T00:04:34Z

A thread can lose its first live events while the initial snapshot or replay starts. A missed assistant-text event can leave an empty reply until the client reloads, even though the server saved the text.

Start the thread's live consumer immediately before reading state, as the shell subscription already does.

The existing snapshot test now publishes without a delay and waits for the synchronization marker. It fails before the fix and passes after it. Eleven focused subscription/coalescer tests and the server typecheck pass. Targeted lint reports only existing unused-parameter warnings in the test file.

Created with GPT-6 Astra (preview) in Codex.

Note

Medium Risk
Changes real-time orchestration WebSocket delivery during subscription startup; incorrect behavior could still drop or reorder early thread events for clients.

Overview
Fixes a race where thread WebSocket subscriptions could drop the first live events while the initial snapshot or replay was still loading—matching behavior subscribeShell already had via startImmediately: true on the scoped fork that feeds the live event coalescer.

The integration test no longer relies on a publish delay or TestClock.withLive; it publishes as soon as the snapshot hook runs, enables requestCompletionMarker, and reads until a synchronized frame so snapshot, event, and completion are all asserted.

^{Reviewed by Cursor Bugbot for commit f4642cf. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Start live-event consumer immediately in `ws.subscribeThread` subscription handler

The scoped fork that consumes the live thread-event stream now starts immediately, so live delivery is attached before the handler proceeds with snapshot or catch-up processing. This prevents events from being missed between the fork and snapshot/replay.
Updates the subscription test in server.test.ts to request a synchronization marker, collect items up to that marker, and assert the sequence contains snapshot, event, and synchronized items.

^{Macroscope summarized f4642cf.}

github-actions · 2026-09-04T00:07:42Z

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.7 KiB	13.8 KiB	+10 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+5 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.7 KiB	6.7 KiB	+5 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.5 KiB	58.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.5 KiB	−75 B (−0.5%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	−71 B (−1.1%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.9 KiB	57.8 KiB	−88 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	8	−2 (−20.0%)	21	✅

Baseline: f8a14b2 · PR result: f4642cf · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

Codex decoded thread snapshot: 113.8 KiB
Claude decoded thread snapshot: 114.5 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

macroscopeapp · 2026-09-04T00:08:36Z

Approvability

Verdict: Approved at f4642cf

Macroscope's review found this PR approvable — This is a narrowly scoped server bug fix that starts the existing thread event consumer before snapshot or replay loading, preventing early events from being lost. The accompanying test deterministically verifies snapshot, event, and synchronization delivery without changing production interfaces or defaults.

^{You can add or adjust custom eligibility rules. Learn more.}

t3dotgg · 2026-09-04T00:04:34Z

A thread can lose its first live events while the initial snapshot or replay starts. A missed assistant-text event can leave an empty reply until the client reloads, even though the server saved the text.

Start the thread's live consumer immediately before reading state, as the shell subscription already does.

The existing snapshot test now publishes without a delay and waits for the synchronization marker. It fails before the fix and passes after it. Eleven focused subscription/coalescer tests and the server typecheck pass. Targeted lint reports only existing unused-parameter warnings in the test file.

Created with GPT-6 Astra (preview) in Codex.

Note

Medium Risk
Changes real-time orchestration WebSocket delivery during subscription startup; incorrect behavior could still drop or reorder early thread events for clients.

Overview
Fixes a race where thread WebSocket subscriptions could drop the first live events while the initial snapshot or replay was still loading—matching behavior subscribeShell already had via startImmediately: true on the scoped fork that feeds the live event coalescer.

The integration test no longer relies on a publish delay or TestClock.withLive; it publishes as soon as the snapshot hook runs, enables requestCompletionMarker, and reads until a synchronized frame so snapshot, event, and completion are all asserted.

^{Reviewed by Cursor Bugbot for commit f4642cf. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Start live-event consumer immediately in `ws.subscribeThread` subscription handler

The scoped fork that consumes the live thread-event stream now starts immediately, so live delivery is attached before the handler proceeds with snapshot or catch-up processing. This prevents events from being missed between the fork and snapshot/replay.
Updates the subscription test in server.test.ts to request a synchronization marker, collect items up to that marker, and assert the sequence contains snapshot, event, and synchronized items.

^{Macroscope summarized f4642cf.}

github-actions · 2026-09-04T00:07:42Z

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.7 KiB	13.8 KiB	+10 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+5 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.7 KiB	6.7 KiB	+5 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.5 KiB	58.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.5 KiB	−75 B (−0.5%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	−71 B (−1.1%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.9 KiB	57.8 KiB	−88 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	8	−2 (−20.0%)	21	✅

Baseline: f8a14b2 · PR result: f4642cf · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

Codex decoded thread snapshot: 113.8 KiB
Claude decoded thread snapshot: 114.5 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

macroscopeapp · 2026-09-04T00:08:36Z

Approvability

Verdict: Approved at f4642cf

Macroscope's review found this PR approvable — This is a narrowly scoped server bug fix that starts the existing thread event consumer before snapshot or replay loading, preventing early events from being lost. The accompanying test deterministically verifies snapshot, event, and synchronization delivery without changing production interfaces or defaults.

^{You can add or adjust custom eligibility rules. Learn more.}

t3dotgg · 2026-09-04T00:04:34Z

A thread can lose its first live events while the initial snapshot or replay starts. A missed assistant-text event can leave an empty reply until the client reloads, even though the server saved the text.

Start the thread's live consumer immediately before reading state, as the shell subscription already does.

The existing snapshot test now publishes without a delay and waits for the synchronization marker. It fails before the fix and passes after it. Eleven focused subscription/coalescer tests and the server typecheck pass. Targeted lint reports only existing unused-parameter warnings in the test file.

Created with GPT-6 Astra (preview) in Codex.

Note

Medium Risk
Changes real-time orchestration WebSocket delivery during subscription startup; incorrect behavior could still drop or reorder early thread events for clients.

Overview
Fixes a race where thread WebSocket subscriptions could drop the first live events while the initial snapshot or replay was still loading—matching behavior subscribeShell already had via startImmediately: true on the scoped fork that feeds the live event coalescer.

The integration test no longer relies on a publish delay or TestClock.withLive; it publishes as soon as the snapshot hook runs, enables requestCompletionMarker, and reads until a synchronized frame so snapshot, event, and completion are all asserted.

^{Reviewed by Cursor Bugbot for commit f4642cf. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Start live-event consumer immediately in `ws.subscribeThread` subscription handler

The scoped fork that consumes the live thread-event stream now starts immediately, so live delivery is attached before the handler proceeds with snapshot or catch-up processing. This prevents events from being missed between the fork and snapshot/replay.
Updates the subscription test in server.test.ts to request a synchronization marker, collect items up to that marker, and assert the sequence contains snapshot, event, and synchronized items.

^{Macroscope summarized f4642cf.}

github-actions · 2026-09-04T00:07:42Z

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.7 KiB	13.8 KiB	+10 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+5 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.7 KiB	6.7 KiB	+5 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.5 KiB	58.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.5 KiB	−75 B (−0.5%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	−71 B (−1.1%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.9 KiB	57.8 KiB	−88 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	8	−2 (−20.0%)	21	✅

Baseline: f8a14b2 · PR result: f4642cf · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

Codex decoded thread snapshot: 113.8 KiB
Claude decoded thread snapshot: 114.5 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

macroscopeapp · 2026-09-04T00:08:36Z

Approvability

Verdict: Approved at f4642cf

Macroscope's review found this PR approvable — This is a narrowly scoped server bug fix that starts the existing thread event consumer before snapshot or replay loading, preventing early events from being lost. The accompanying test deterministically verifies snapshot, event, and synchronization delivery without changing production interfaces or defaults.

^{You can add or adjust custom eligibility rules. Learn more.}

t3dotgg · 2026-09-04T00:04:34Z

A thread can lose its first live events while the initial snapshot or replay starts. A missed assistant-text event can leave an empty reply until the client reloads, even though the server saved the text.

Start the thread's live consumer immediately before reading state, as the shell subscription already does.

The existing snapshot test now publishes without a delay and waits for the synchronization marker. It fails before the fix and passes after it. Eleven focused subscription/coalescer tests and the server typecheck pass. Targeted lint reports only existing unused-parameter warnings in the test file.

Created with GPT-6 Astra (preview) in Codex.

Note

Medium Risk
Changes real-time orchestration WebSocket delivery during subscription startup; incorrect behavior could still drop or reorder early thread events for clients.

Overview
Fixes a race where thread WebSocket subscriptions could drop the first live events while the initial snapshot or replay was still loading—matching behavior subscribeShell already had via startImmediately: true on the scoped fork that feeds the live event coalescer.

The integration test no longer relies on a publish delay or TestClock.withLive; it publishes as soon as the snapshot hook runs, enables requestCompletionMarker, and reads until a synchronized frame so snapshot, event, and completion are all asserted.

^{Reviewed by Cursor Bugbot for commit f4642cf. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Start live-event consumer immediately in `ws.subscribeThread` subscription handler

The scoped fork that consumes the live thread-event stream now starts immediately, so live delivery is attached before the handler proceeds with snapshot or catch-up processing. This prevents events from being missed between the fork and snapshot/replay.
Updates the subscription test in server.test.ts to request a synchronization marker, collect items up to that marker, and assert the sequence contains snapshot, event, and synchronized items.

^{Macroscope summarized f4642cf.}

github-actions · 2026-09-04T00:07:42Z

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.7 KiB	13.8 KiB	+10 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+5 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.7 KiB	6.7 KiB	+5 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.5 KiB	58.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.5 KiB	−75 B (−0.5%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	−71 B (−1.1%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.9 KiB	57.8 KiB	−88 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	8	−2 (−20.0%)	21	✅

Baseline: f8a14b2 · PR result: f4642cf · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

Codex decoded thread snapshot: 113.8 KiB
Claude decoded thread snapshot: 114.5 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

macroscopeapp · 2026-09-04T00:08:36Z

Approvability

Verdict: Approved at f4642cf

Macroscope's review found this PR approvable — This is a narrowly scoped server bug fix that starts the existing thread event consumer before snapshot or replay loading, preventing early events from being lost. The accompanying test deterministically verifies snapshot, event, and synchronization delivery without changing production interfaces or defaults.

^{You can add or adjust custom eligibility rules. Learn more.}

t3dotgg · 2026-09-04T00:04:34Z

A thread can lose its first live events while the initial snapshot or replay starts. A missed assistant-text event can leave an empty reply until the client reloads, even though the server saved the text.

Start the thread's live consumer immediately before reading state, as the shell subscription already does.

The existing snapshot test now publishes without a delay and waits for the synchronization marker. It fails before the fix and passes after it. Eleven focused subscription/coalescer tests and the server typecheck pass. Targeted lint reports only existing unused-parameter warnings in the test file.

Created with GPT-6 Astra (preview) in Codex.

Note

Medium Risk
Changes real-time orchestration WebSocket delivery during subscription startup; incorrect behavior could still drop or reorder early thread events for clients.

Overview
Fixes a race where thread WebSocket subscriptions could drop the first live events while the initial snapshot or replay was still loading—matching behavior subscribeShell already had via startImmediately: true on the scoped fork that feeds the live event coalescer.

The integration test no longer relies on a publish delay or TestClock.withLive; it publishes as soon as the snapshot hook runs, enables requestCompletionMarker, and reads until a synchronized frame so snapshot, event, and completion are all asserted.

^{Reviewed by Cursor Bugbot for commit f4642cf. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Start live-event consumer immediately in `ws.subscribeThread` subscription handler

The scoped fork that consumes the live thread-event stream now starts immediately, so live delivery is attached before the handler proceeds with snapshot or catch-up processing. This prevents events from being missed between the fork and snapshot/replay.
Updates the subscription test in server.test.ts to request a synchronization marker, collect items up to that marker, and assert the sequence contains snapshot, event, and synchronized items.

^{Macroscope summarized f4642cf.}

github-actions · 2026-09-04T00:07:42Z

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.7 KiB	13.8 KiB	+10 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+5 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.7 KiB	6.7 KiB	+5 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.5 KiB	58.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.5 KiB	−75 B (−0.5%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	−71 B (−1.1%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.9 KiB	57.8 KiB	−88 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	8	−2 (−20.0%)	21	✅

Baseline: f8a14b2 · PR result: f4642cf · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

Codex decoded thread snapshot: 113.8 KiB
Claude decoded thread snapshot: 114.5 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

macroscopeapp · 2026-09-04T00:08:36Z

Approvability

Verdict: Approved at f4642cf

Macroscope's review found this PR approvable — This is a narrowly scoped server bug fix that starts the existing thread event consumer before snapshot or replay loading, preventing early events from being lost. The accompanying test deterministically verifies snapshot, event, and synchronization delivery without changing production interfaces or defaults.

^{You can add or adjust custom eligibility rules. Learn more.}

fix(server): keep events during thread subscription startup
f4642cf

github-actionsBot added vouch:trusted PR author is trusted by repo permissions or the VOUCHED list. size:XS 0-9 changed lines (additions + deletions). labels Sep 4, 2026

macroscopeappBot approved these changes Sep 4, 2026
View reviewed changes

t3dotgg merged commit 9c9ae3d into mainSep 4, 2026
22 checks passed

t3dotgg deleted the t3code/thread-subscription-gap branch September 4, 2026 00:08

berghtho mentioned this pull request Sep 4, 2026
chore(upstream): sync 2026-09-04 berghtho/t3code#26
Draft