fix(server): stop titling linked PR threads from local git history

[t3dotgg]

When a user starts a thread with a PR link and a generic action such as "take over", the title generator tries to read the PR with gh. That call fails inside the Codex read-only sandbox, which has no network. The model then falls back to git log in the checkout and titles the thread after whatever it finds there. On a fresh takeover branch that is the tip of main, so the title names an unrelated change that already merged.

Real examples from this machine:

Thread message	Generated title	Actual PR
$takeover https://github.com/pingdotgg/t3code/pull/8588	Open Projects in Desktop App	fix(desktop): show newest changes in nightly previews
https://github.com/pingdotgg/t3code/pull/8235 Take over this PR.	Limit OpenCode Native Attachments	feat(server): accept PDF, ZIP, and other file uploads

The fix adds two rules to both the initial and regeneration title prompts. Local git history is not evidence of what a linked PR is about. When the linked item cannot be read, the title falls back to the user's action plus the PR number, such as "Take Over PR 8588".

Testing

I ran the real prompt through codex exec with the same flags the server uses, from this worktree, with the exact messages above.

Before: 1 of 4 runs for PR 8235 produced "Fix automatic thread title generation" from unrelated commits in the checkout. Other runs varied between "Support 50MB File Uploads" (found via a local ref) and "Take Over PR 8235".

After: 5 of 5 runs for PR 8235 returned "Take Over PR 8235". 5 of 5 runs for PR 8588 returned "Take Over PR 8588" (one said "Taking Over"). 8 of 8 runs in a synthetic repo whose branch tip is a merge from main returned takeover titles with no git log calls.

vp test run apps/server/src/textGeneration/TextGenerationPrompts.test.ts passes.

Written by Claude Fable 5.1 through Claude Code in T3 Code.

---

Note

Low Risk
Prompt-only change to automatic thread titles with no auth, data, or API behavior changes; risk is limited to title wording quality.

Overview
Thread title prompts now tell the model not to infer linked PR or issue subjects from local git history (branch names, commits on main, etc.) when gh or other tools cannot fetch the link—common in read-only sandboxes.

When the linked item still cannot be read, titles should fall back to the user’s stated action plus the PR/issue number (e.g. Take Over PR 8588), which is explicitly allowed as the only case where a number belongs in the title. The same rules were added to initial and regeneration title prompts, with a small tweak to prefer inspecting URLs/attachments directly instead of guessing.

Parameterized tests assert both prompt paths include the new guidance for takeover-style messages.

^{Reviewed by Cursor Bugbot for commit 06061e9. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Stop using local git history for linked-PR thread titles in buildThreadTitlePrompt

• Updates buildThreadTitlePrompt and regenerateThreadTitlePrompt to instruct the model to inspect URL or attachment sources directly instead of using local checkout history (branch names, commit messages, merged commits)
• Adds an action-plus-PR-number fallback title (e.g. a takeover title) when the linked resource cannot be read
• Adds parameterized test coverage in TextGenerationPrompts.test.ts for both initial and regeneration prompts
• Behavioral Change: thread titles for linked PR/issue threads may now differ from previous outputs since the model is told to ignore local git history

^{Macroscope summarized 06061e9.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.4 KiB	13.5 KiB	+17 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	6.9 KiB	6.9 KiB	+9 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	+8 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.2 KiB	13.2 KiB	+6 B (+0.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	6.9 KiB	6.9 KiB	+5 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.3 KiB	6.3 KiB	+1 B (+0.0%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	56.3 KiB	56.3 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	8	8	0 (0.0%)	21	✅

Baseline: dd6879f · PR result: 06061e9 · 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: 109.4 KiB
• Claude decoded thread snapshot: 110.1 KiB

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

[macroscopeapp]

Approvability

Verdict: Approved at 06061e9

Macroscope's review found this PR approvable — This is a small, self-contained prompt fix with tests covering both title-generation paths. Runtime impact is limited to improving titles for unreadable linked PRs or issues, with no API, schema, security, billing, or deployment changes.

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

[t3dotgg]

When a user starts a thread with a PR link and a generic action such as "take over", the title generator tries to read the PR with gh. That call fails inside the Codex read-only sandbox, which has no network. The model then falls back to git log in the checkout and titles the thread after whatever it finds there. On a fresh takeover branch that is the tip of main, so the title names an unrelated change that already merged.

Real examples from this machine:

Thread message	Generated title	Actual PR
$takeover https://github.com/pingdotgg/t3code/pull/8588	Open Projects in Desktop App	fix(desktop): show newest changes in nightly previews
https://github.com/pingdotgg/t3code/pull/8235 Take over this PR.	Limit OpenCode Native Attachments	feat(server): accept PDF, ZIP, and other file uploads

The fix adds two rules to both the initial and regeneration title prompts. Local git history is not evidence of what a linked PR is about. When the linked item cannot be read, the title falls back to the user's action plus the PR number, such as "Take Over PR 8588".

Testing

I ran the real prompt through codex exec with the same flags the server uses, from this worktree, with the exact messages above.

Before: 1 of 4 runs for PR 8235 produced "Fix automatic thread title generation" from unrelated commits in the checkout. Other runs varied between "Support 50MB File Uploads" (found via a local ref) and "Take Over PR 8235".

After: 5 of 5 runs for PR 8235 returned "Take Over PR 8235". 5 of 5 runs for PR 8588 returned "Take Over PR 8588" (one said "Taking Over"). 8 of 8 runs in a synthetic repo whose branch tip is a merge from main returned takeover titles with no git log calls.

vp test run apps/server/src/textGeneration/TextGenerationPrompts.test.ts passes.

Written by Claude Fable 5.1 through Claude Code in T3 Code.

---

Note

Low Risk
Prompt-only change to automatic thread titles with no auth, data, or API behavior changes; risk is limited to title wording quality.

Overview
Thread title prompts now tell the model not to infer linked PR or issue subjects from local git history (branch names, commits on main, etc.) when gh or other tools cannot fetch the link—common in read-only sandboxes.

When the linked item still cannot be read, titles should fall back to the user’s stated action plus the PR/issue number (e.g. Take Over PR 8588), which is explicitly allowed as the only case where a number belongs in the title. The same rules were added to initial and regeneration title prompts, with a small tweak to prefer inspecting URLs/attachments directly instead of guessing.

Parameterized tests assert both prompt paths include the new guidance for takeover-style messages.

^{Reviewed by Cursor Bugbot for commit 06061e9. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Stop using local git history for linked-PR thread titles in buildThreadTitlePrompt

• Updates buildThreadTitlePrompt and regenerateThreadTitlePrompt to instruct the model to inspect URL or attachment sources directly instead of using local checkout history (branch names, commit messages, merged commits)
• Adds an action-plus-PR-number fallback title (e.g. a takeover title) when the linked resource cannot be read
• Adds parameterized test coverage in TextGenerationPrompts.test.ts for both initial and regeneration prompts
• Behavioral Change: thread titles for linked PR/issue threads may now differ from previous outputs since the model is told to ignore local git history

^{Macroscope summarized 06061e9.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.4 KiB	13.5 KiB	+17 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	6.9 KiB	6.9 KiB	+9 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	+8 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.2 KiB	13.2 KiB	+6 B (+0.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	6.9 KiB	6.9 KiB	+5 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.3 KiB	6.3 KiB	+1 B (+0.0%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	56.3 KiB	56.3 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	8	8	0 (0.0%)	21	✅

Baseline: dd6879f · PR result: 06061e9 · 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: 109.4 KiB
• Claude decoded thread snapshot: 110.1 KiB

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

[macroscopeapp]

Approvability

Verdict: Approved at 06061e9

Macroscope's review found this PR approvable — This is a small, self-contained prompt fix with tests covering both title-generation paths. Runtime impact is limited to improving titles for unreadable linked PRs or issues, with no API, schema, security, billing, or deployment changes.

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

[t3dotgg]

When a user starts a thread with a PR link and a generic action such as "take over", the title generator tries to read the PR with gh. That call fails inside the Codex read-only sandbox, which has no network. The model then falls back to git log in the checkout and titles the thread after whatever it finds there. On a fresh takeover branch that is the tip of main, so the title names an unrelated change that already merged.

Real examples from this machine:

Thread message	Generated title	Actual PR
$takeover https://github.com/pingdotgg/t3code/pull/8588	Open Projects in Desktop App	fix(desktop): show newest changes in nightly previews
https://github.com/pingdotgg/t3code/pull/8235 Take over this PR.	Limit OpenCode Native Attachments	feat(server): accept PDF, ZIP, and other file uploads

The fix adds two rules to both the initial and regeneration title prompts. Local git history is not evidence of what a linked PR is about. When the linked item cannot be read, the title falls back to the user's action plus the PR number, such as "Take Over PR 8588".

Testing

I ran the real prompt through codex exec with the same flags the server uses, from this worktree, with the exact messages above.

Before: 1 of 4 runs for PR 8235 produced "Fix automatic thread title generation" from unrelated commits in the checkout. Other runs varied between "Support 50MB File Uploads" (found via a local ref) and "Take Over PR 8235".

After: 5 of 5 runs for PR 8235 returned "Take Over PR 8235". 5 of 5 runs for PR 8588 returned "Take Over PR 8588" (one said "Taking Over"). 8 of 8 runs in a synthetic repo whose branch tip is a merge from main returned takeover titles with no git log calls.

vp test run apps/server/src/textGeneration/TextGenerationPrompts.test.ts passes.

Written by Claude Fable 5.1 through Claude Code in T3 Code.

---

Note

Low Risk
Prompt-only change to automatic thread titles with no auth, data, or API behavior changes; risk is limited to title wording quality.

Overview
Thread title prompts now tell the model not to infer linked PR or issue subjects from local git history (branch names, commits on main, etc.) when gh or other tools cannot fetch the link—common in read-only sandboxes.

When the linked item still cannot be read, titles should fall back to the user’s stated action plus the PR/issue number (e.g. Take Over PR 8588), which is explicitly allowed as the only case where a number belongs in the title. The same rules were added to initial and regeneration title prompts, with a small tweak to prefer inspecting URLs/attachments directly instead of guessing.

Parameterized tests assert both prompt paths include the new guidance for takeover-style messages.

^{Reviewed by Cursor Bugbot for commit 06061e9. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Stop using local git history for linked-PR thread titles in buildThreadTitlePrompt

• Updates buildThreadTitlePrompt and regenerateThreadTitlePrompt to instruct the model to inspect URL or attachment sources directly instead of using local checkout history (branch names, commit messages, merged commits)
• Adds an action-plus-PR-number fallback title (e.g. a takeover title) when the linked resource cannot be read
• Adds parameterized test coverage in TextGenerationPrompts.test.ts for both initial and regeneration prompts
• Behavioral Change: thread titles for linked PR/issue threads may now differ from previous outputs since the model is told to ignore local git history

^{Macroscope summarized 06061e9.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.4 KiB	13.5 KiB	+17 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	6.9 KiB	6.9 KiB	+9 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	+8 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.2 KiB	13.2 KiB	+6 B (+0.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	6.9 KiB	6.9 KiB	+5 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.3 KiB	6.3 KiB	+1 B (+0.0%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	56.3 KiB	56.3 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	8	8	0 (0.0%)	21	✅

Baseline: dd6879f · PR result: 06061e9 · 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: 109.4 KiB
• Claude decoded thread snapshot: 110.1 KiB

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

[macroscopeapp]

Approvability

Verdict: Approved at 06061e9

Macroscope's review found this PR approvable — This is a small, self-contained prompt fix with tests covering both title-generation paths. Runtime impact is limited to improving titles for unreadable linked PRs or issues, with no API, schema, security, billing, or deployment changes.

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

[t3dotgg]

When a user starts a thread with a PR link and a generic action such as "take over", the title generator tries to read the PR with gh. That call fails inside the Codex read-only sandbox, which has no network. The model then falls back to git log in the checkout and titles the thread after whatever it finds there. On a fresh takeover branch that is the tip of main, so the title names an unrelated change that already merged.

Real examples from this machine:

Thread message	Generated title	Actual PR
$takeover https://github.com/pingdotgg/t3code/pull/8588	Open Projects in Desktop App	fix(desktop): show newest changes in nightly previews
https://github.com/pingdotgg/t3code/pull/8235 Take over this PR.	Limit OpenCode Native Attachments	feat(server): accept PDF, ZIP, and other file uploads

The fix adds two rules to both the initial and regeneration title prompts. Local git history is not evidence of what a linked PR is about. When the linked item cannot be read, the title falls back to the user's action plus the PR number, such as "Take Over PR 8588".

Testing

I ran the real prompt through codex exec with the same flags the server uses, from this worktree, with the exact messages above.

Before: 1 of 4 runs for PR 8235 produced "Fix automatic thread title generation" from unrelated commits in the checkout. Other runs varied between "Support 50MB File Uploads" (found via a local ref) and "Take Over PR 8235".

After: 5 of 5 runs for PR 8235 returned "Take Over PR 8235". 5 of 5 runs for PR 8588 returned "Take Over PR 8588" (one said "Taking Over"). 8 of 8 runs in a synthetic repo whose branch tip is a merge from main returned takeover titles with no git log calls.

vp test run apps/server/src/textGeneration/TextGenerationPrompts.test.ts passes.

Written by Claude Fable 5.1 through Claude Code in T3 Code.

---

Note

Low Risk
Prompt-only change to automatic thread titles with no auth, data, or API behavior changes; risk is limited to title wording quality.

Overview
Thread title prompts now tell the model not to infer linked PR or issue subjects from local git history (branch names, commits on main, etc.) when gh or other tools cannot fetch the link—common in read-only sandboxes.

When the linked item still cannot be read, titles should fall back to the user’s stated action plus the PR/issue number (e.g. Take Over PR 8588), which is explicitly allowed as the only case where a number belongs in the title. The same rules were added to initial and regeneration title prompts, with a small tweak to prefer inspecting URLs/attachments directly instead of guessing.

Parameterized tests assert both prompt paths include the new guidance for takeover-style messages.

^{Reviewed by Cursor Bugbot for commit 06061e9. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Stop using local git history for linked-PR thread titles in buildThreadTitlePrompt

• Updates buildThreadTitlePrompt and regenerateThreadTitlePrompt to instruct the model to inspect URL or attachment sources directly instead of using local checkout history (branch names, commit messages, merged commits)
• Adds an action-plus-PR-number fallback title (e.g. a takeover title) when the linked resource cannot be read
• Adds parameterized test coverage in TextGenerationPrompts.test.ts for both initial and regeneration prompts
• Behavioral Change: thread titles for linked PR/issue threads may now differ from previous outputs since the model is told to ignore local git history

^{Macroscope summarized 06061e9.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.4 KiB	13.5 KiB	+17 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	6.9 KiB	6.9 KiB	+9 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	+8 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.2 KiB	13.2 KiB	+6 B (+0.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	6.9 KiB	6.9 KiB	+5 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.3 KiB	6.3 KiB	+1 B (+0.0%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	56.3 KiB	56.3 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	8	8	0 (0.0%)	21	✅

Baseline: dd6879f · PR result: 06061e9 · 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: 109.4 KiB
• Claude decoded thread snapshot: 110.1 KiB

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

[macroscopeapp]

Approvability

Verdict: Approved at 06061e9

Macroscope's review found this PR approvable — This is a small, self-contained prompt fix with tests covering both title-generation paths. Runtime impact is limited to improving titles for unreadable linked PRs or issues, with no API, schema, security, billing, or deployment changes.

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

[t3dotgg]

When a user starts a thread with a PR link and a generic action such as "take over", the title generator tries to read the PR with gh. That call fails inside the Codex read-only sandbox, which has no network. The model then falls back to git log in the checkout and titles the thread after whatever it finds there. On a fresh takeover branch that is the tip of main, so the title names an unrelated change that already merged.

Real examples from this machine:

Thread message	Generated title	Actual PR
$takeover https://github.com/pingdotgg/t3code/pull/8588	Open Projects in Desktop App	fix(desktop): show newest changes in nightly previews
https://github.com/pingdotgg/t3code/pull/8235 Take over this PR.	Limit OpenCode Native Attachments	feat(server): accept PDF, ZIP, and other file uploads

The fix adds two rules to both the initial and regeneration title prompts. Local git history is not evidence of what a linked PR is about. When the linked item cannot be read, the title falls back to the user's action plus the PR number, such as "Take Over PR 8588".

Testing

I ran the real prompt through codex exec with the same flags the server uses, from this worktree, with the exact messages above.

Before: 1 of 4 runs for PR 8235 produced "Fix automatic thread title generation" from unrelated commits in the checkout. Other runs varied between "Support 50MB File Uploads" (found via a local ref) and "Take Over PR 8235".

After: 5 of 5 runs for PR 8235 returned "Take Over PR 8235". 5 of 5 runs for PR 8588 returned "Take Over PR 8588" (one said "Taking Over"). 8 of 8 runs in a synthetic repo whose branch tip is a merge from main returned takeover titles with no git log calls.

vp test run apps/server/src/textGeneration/TextGenerationPrompts.test.ts passes.

Written by Claude Fable 5.1 through Claude Code in T3 Code.

---

Note

Low Risk
Prompt-only change to automatic thread titles with no auth, data, or API behavior changes; risk is limited to title wording quality.

Overview
Thread title prompts now tell the model not to infer linked PR or issue subjects from local git history (branch names, commits on main, etc.) when gh or other tools cannot fetch the link—common in read-only sandboxes.

When the linked item still cannot be read, titles should fall back to the user’s stated action plus the PR/issue number (e.g. Take Over PR 8588), which is explicitly allowed as the only case where a number belongs in the title. The same rules were added to initial and regeneration title prompts, with a small tweak to prefer inspecting URLs/attachments directly instead of guessing.

Parameterized tests assert both prompt paths include the new guidance for takeover-style messages.

^{Reviewed by Cursor Bugbot for commit 06061e9. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Stop using local git history for linked-PR thread titles in buildThreadTitlePrompt

• Updates buildThreadTitlePrompt and regenerateThreadTitlePrompt to instruct the model to inspect URL or attachment sources directly instead of using local checkout history (branch names, commit messages, merged commits)
• Adds an action-plus-PR-number fallback title (e.g. a takeover title) when the linked resource cannot be read
• Adds parameterized test coverage in TextGenerationPrompts.test.ts for both initial and regeneration prompts
• Behavioral Change: thread titles for linked PR/issue threads may now differ from previous outputs since the model is told to ignore local git history

^{Macroscope summarized 06061e9.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.4 KiB	13.5 KiB	+17 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	6.9 KiB	6.9 KiB	+9 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	+8 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.2 KiB	13.2 KiB	+6 B (+0.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	6.9 KiB	6.9 KiB	+5 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.3 KiB	6.3 KiB	+1 B (+0.0%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	56.3 KiB	56.3 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	8	8	0 (0.0%)	21	✅

Baseline: dd6879f · PR result: 06061e9 · 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: 109.4 KiB
• Claude decoded thread snapshot: 110.1 KiB

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

[macroscopeapp]

Approvability

Verdict: Approved at 06061e9

Macroscope's review found this PR approvable — This is a small, self-contained prompt fix with tests covering both title-generation paths. Runtime impact is limited to improving titles for unreadable linked PRs or issues, with no API, schema, security, billing, or deployment changes.

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

[t3dotgg]

When a user starts a thread with a PR link and a generic action such as "take over", the title generator tries to read the PR with gh. That call fails inside the Codex read-only sandbox, which has no network. The model then falls back to git log in the checkout and titles the thread after whatever it finds there. On a fresh takeover branch that is the tip of main, so the title names an unrelated change that already merged.

Real examples from this machine:

Thread message	Generated title	Actual PR
$takeover https://github.com/pingdotgg/t3code/pull/8588	Open Projects in Desktop App	fix(desktop): show newest changes in nightly previews
https://github.com/pingdotgg/t3code/pull/8235 Take over this PR.	Limit OpenCode Native Attachments	feat(server): accept PDF, ZIP, and other file uploads

The fix adds two rules to both the initial and regeneration title prompts. Local git history is not evidence of what a linked PR is about. When the linked item cannot be read, the title falls back to the user's action plus the PR number, such as "Take Over PR 8588".

Testing

I ran the real prompt through codex exec with the same flags the server uses, from this worktree, with the exact messages above.

Before: 1 of 4 runs for PR 8235 produced "Fix automatic thread title generation" from unrelated commits in the checkout. Other runs varied between "Support 50MB File Uploads" (found via a local ref) and "Take Over PR 8235".

After: 5 of 5 runs for PR 8235 returned "Take Over PR 8235". 5 of 5 runs for PR 8588 returned "Take Over PR 8588" (one said "Taking Over"). 8 of 8 runs in a synthetic repo whose branch tip is a merge from main returned takeover titles with no git log calls.

vp test run apps/server/src/textGeneration/TextGenerationPrompts.test.ts passes.

Written by Claude Fable 5.1 through Claude Code in T3 Code.

---

Note

Low Risk
Prompt-only change to automatic thread titles with no auth, data, or API behavior changes; risk is limited to title wording quality.

Overview
Thread title prompts now tell the model not to infer linked PR or issue subjects from local git history (branch names, commits on main, etc.) when gh or other tools cannot fetch the link—common in read-only sandboxes.

When the linked item still cannot be read, titles should fall back to the user’s stated action plus the PR/issue number (e.g. Take Over PR 8588), which is explicitly allowed as the only case where a number belongs in the title. The same rules were added to initial and regeneration title prompts, with a small tweak to prefer inspecting URLs/attachments directly instead of guessing.

Parameterized tests assert both prompt paths include the new guidance for takeover-style messages.

^{Reviewed by Cursor Bugbot for commit 06061e9. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Stop using local git history for linked-PR thread titles in buildThreadTitlePrompt

• Updates buildThreadTitlePrompt and regenerateThreadTitlePrompt to instruct the model to inspect URL or attachment sources directly instead of using local checkout history (branch names, commit messages, merged commits)
• Adds an action-plus-PR-number fallback title (e.g. a takeover title) when the linked resource cannot be read
• Adds parameterized test coverage in TextGenerationPrompts.test.ts for both initial and regeneration prompts
• Behavioral Change: thread titles for linked PR/issue threads may now differ from previous outputs since the model is told to ignore local git history

^{Macroscope summarized 06061e9.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.4 KiB	13.5 KiB	+17 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	6.9 KiB	6.9 KiB	+9 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	+8 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.2 KiB	13.2 KiB	+6 B (+0.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	6.9 KiB	6.9 KiB	+5 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.3 KiB	6.3 KiB	+1 B (+0.0%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	56.3 KiB	56.3 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	8	8	0 (0.0%)	21	✅

Baseline: dd6879f · PR result: 06061e9 · 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: 109.4 KiB
• Claude decoded thread snapshot: 110.1 KiB

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

[macroscopeapp]

Approvability

Verdict: Approved at 06061e9

Macroscope's review found this PR approvable — This is a small, self-contained prompt fix with tests covering both title-generation paths. Runtime impact is limited to improving titles for unreadable linked PRs or issues, with no API, schema, security, billing, or deployment changes.

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

[t3dotgg]

When a user starts a thread with a PR link and a generic action such as "take over", the title generator tries to read the PR with gh. That call fails inside the Codex read-only sandbox, which has no network. The model then falls back to git log in the checkout and titles the thread after whatever it finds there. On a fresh takeover branch that is the tip of main, so the title names an unrelated change that already merged.

Real examples from this machine:

Thread message	Generated title	Actual PR
$takeover https://github.com/pingdotgg/t3code/pull/8588	Open Projects in Desktop App	fix(desktop): show newest changes in nightly previews
https://github.com/pingdotgg/t3code/pull/8235 Take over this PR.	Limit OpenCode Native Attachments	feat(server): accept PDF, ZIP, and other file uploads

The fix adds two rules to both the initial and regeneration title prompts. Local git history is not evidence of what a linked PR is about. When the linked item cannot be read, the title falls back to the user's action plus the PR number, such as "Take Over PR 8588".

Testing

I ran the real prompt through codex exec with the same flags the server uses, from this worktree, with the exact messages above.

Before: 1 of 4 runs for PR 8235 produced "Fix automatic thread title generation" from unrelated commits in the checkout. Other runs varied between "Support 50MB File Uploads" (found via a local ref) and "Take Over PR 8235".

After: 5 of 5 runs for PR 8235 returned "Take Over PR 8235". 5 of 5 runs for PR 8588 returned "Take Over PR 8588" (one said "Taking Over"). 8 of 8 runs in a synthetic repo whose branch tip is a merge from main returned takeover titles with no git log calls.

vp test run apps/server/src/textGeneration/TextGenerationPrompts.test.ts passes.

Written by Claude Fable 5.1 through Claude Code in T3 Code.

---

Note

Low Risk
Prompt-only change to automatic thread titles with no auth, data, or API behavior changes; risk is limited to title wording quality.

Overview
Thread title prompts now tell the model not to infer linked PR or issue subjects from local git history (branch names, commits on main, etc.) when gh or other tools cannot fetch the link—common in read-only sandboxes.

When the linked item still cannot be read, titles should fall back to the user’s stated action plus the PR/issue number (e.g. Take Over PR 8588), which is explicitly allowed as the only case where a number belongs in the title. The same rules were added to initial and regeneration title prompts, with a small tweak to prefer inspecting URLs/attachments directly instead of guessing.

Parameterized tests assert both prompt paths include the new guidance for takeover-style messages.

^{Reviewed by Cursor Bugbot for commit 06061e9. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Stop using local git history for linked-PR thread titles in buildThreadTitlePrompt

• Updates buildThreadTitlePrompt and regenerateThreadTitlePrompt to instruct the model to inspect URL or attachment sources directly instead of using local checkout history (branch names, commit messages, merged commits)
• Adds an action-plus-PR-number fallback title (e.g. a takeover title) when the linked resource cannot be read
• Adds parameterized test coverage in TextGenerationPrompts.test.ts for both initial and regeneration prompts
• Behavioral Change: thread titles for linked PR/issue threads may now differ from previous outputs since the model is told to ignore local git history

^{Macroscope summarized 06061e9.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.4 KiB	13.5 KiB	+17 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	6.9 KiB	6.9 KiB	+9 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	+8 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.2 KiB	13.2 KiB	+6 B (+0.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	6.9 KiB	6.9 KiB	+5 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.3 KiB	6.3 KiB	+1 B (+0.0%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	56.3 KiB	56.3 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	8	8	0 (0.0%)	21	✅

Baseline: dd6879f · PR result: 06061e9 · 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: 109.4 KiB
• Claude decoded thread snapshot: 110.1 KiB

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

[macroscopeapp]

Approvability

Verdict: Approved at 06061e9

Macroscope's review found this PR approvable — This is a small, self-contained prompt fix with tests covering both title-generation paths. Runtime impact is limited to improving titles for unreadable linked PRs or issues, with no API, schema, security, billing, or deployment changes.

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

[t3dotgg]

When a user starts a thread with a PR link and a generic action such as "take over", the title generator tries to read the PR with gh. That call fails inside the Codex read-only sandbox, which has no network. The model then falls back to git log in the checkout and titles the thread after whatever it finds there. On a fresh takeover branch that is the tip of main, so the title names an unrelated change that already merged.

Real examples from this machine:

Thread message	Generated title	Actual PR
$takeover https://github.com/pingdotgg/t3code/pull/8588	Open Projects in Desktop App	fix(desktop): show newest changes in nightly previews
https://github.com/pingdotgg/t3code/pull/8235 Take over this PR.	Limit OpenCode Native Attachments	feat(server): accept PDF, ZIP, and other file uploads

The fix adds two rules to both the initial and regeneration title prompts. Local git history is not evidence of what a linked PR is about. When the linked item cannot be read, the title falls back to the user's action plus the PR number, such as "Take Over PR 8588".

Testing

I ran the real prompt through codex exec with the same flags the server uses, from this worktree, with the exact messages above.

Before: 1 of 4 runs for PR 8235 produced "Fix automatic thread title generation" from unrelated commits in the checkout. Other runs varied between "Support 50MB File Uploads" (found via a local ref) and "Take Over PR 8235".

After: 5 of 5 runs for PR 8235 returned "Take Over PR 8235". 5 of 5 runs for PR 8588 returned "Take Over PR 8588" (one said "Taking Over"). 8 of 8 runs in a synthetic repo whose branch tip is a merge from main returned takeover titles with no git log calls.

vp test run apps/server/src/textGeneration/TextGenerationPrompts.test.ts passes.

Written by Claude Fable 5.1 through Claude Code in T3 Code.

---

Note

Low Risk
Prompt-only change to automatic thread titles with no auth, data, or API behavior changes; risk is limited to title wording quality.

Overview
Thread title prompts now tell the model not to infer linked PR or issue subjects from local git history (branch names, commits on main, etc.) when gh or other tools cannot fetch the link—common in read-only sandboxes.

When the linked item still cannot be read, titles should fall back to the user’s stated action plus the PR/issue number (e.g. Take Over PR 8588), which is explicitly allowed as the only case where a number belongs in the title. The same rules were added to initial and regeneration title prompts, with a small tweak to prefer inspecting URLs/attachments directly instead of guessing.

Parameterized tests assert both prompt paths include the new guidance for takeover-style messages.

^{Reviewed by Cursor Bugbot for commit 06061e9. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Stop using local git history for linked-PR thread titles in buildThreadTitlePrompt

• Updates buildThreadTitlePrompt and regenerateThreadTitlePrompt to instruct the model to inspect URL or attachment sources directly instead of using local checkout history (branch names, commit messages, merged commits)
• Adds an action-plus-PR-number fallback title (e.g. a takeover title) when the linked resource cannot be read
• Adds parameterized test coverage in TextGenerationPrompts.test.ts for both initial and regeneration prompts
• Behavioral Change: thread titles for linked PR/issue threads may now differ from previous outputs since the model is told to ignore local git history

^{Macroscope summarized 06061e9.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.4 KiB	13.5 KiB	+17 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	6.9 KiB	6.9 KiB	+9 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	+8 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.2 KiB	13.2 KiB	+6 B (+0.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	6.9 KiB	6.9 KiB	+5 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.3 KiB	6.3 KiB	+1 B (+0.0%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	56.3 KiB	56.3 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	8	8	0 (0.0%)	21	✅

Baseline: dd6879f · PR result: 06061e9 · 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: 109.4 KiB
• Claude decoded thread snapshot: 110.1 KiB

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

[macroscopeapp]

Approvability

Verdict: Approved at 06061e9

Macroscope's review found this PR approvable — This is a small, self-contained prompt fix with tests covering both title-generation paths. Runtime impact is limited to improving titles for unreadable linked PRs or issues, with no API, schema, security, billing, or deployment changes.

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