# Manual web reproduction

Both runs: real app dev server and Codex provider, separate fresh T3 homes with automatic seeding disabled, synthetic Git project created by seed.py, local self-remote with dev branch, Chromium at 1280 x 800 CSS pixels, light theme. Runtime model selection was identical and its button was hidden with CSS in both recordings for privacy. No lifecycle status or transcript content was altered. Each server ran the exact named commit.

Base: 3a8c250cb0c8056f2f563091fd412fe5db809fa1
Head: cc1cd4d68cadfc4df69895f243b8394da828d1a5

1. Start each checkout separately with T3CODE_DEV_SEED=0, a fresh --home-dir, and a loopback web dev server; configure Codex identically. Run seed.py CHECKOUT ISOLATED_T3_HOME.
2. Pair the browser, open the new thread in handoff-demo, and close the thread details panel.
3. Fill [data-testid="composer-editor"] with the following exact prompt, start recording, and press Enter:

> Call t3_worktree_handoff with branch "handoff-proof", baseRef "dev", startFromOrigin true, runSetupScript false, and continuationPrompt "Run pwd and git branch --show-current, verify the cwd is the new worktree and branch is handoff-proof, then report HANDOFF CONTINUATION COMPLETE and the branch. Keep the absolute directory private." Do not ask questions. Do not call any stop tool.

4. Never press Stop during the handoff. Wait for the continuation's final response and the submit button to replace Stop generation. Blur the composer and capture the settled conversation. Two captures over 500 ms apart matched pixel for pixel on each side.
5. Base: continuation succeeded on handoff-proof, but the previous run showed Run interrupted / Stopped by the provider. Head: both runs completed, the previous run showed Worked for, and there was no interrupted divider. inspect-runtime.py confirms both head checkpoints are ready and their Git refs exist. Base also captured checkpoints in this reproduction; the demonstrated regression is its false interrupted status.
6. Head-only Stop control: send "Stop control check: run sleep 120 and wait for that command. Do not do other work." Once Running sleep appears, click Stop generation. It shows Run interrupted / Stopped by user. Record and capture this separately.

The supplied reproduction mentioned an absolute sibling path. Neither commit's tool schema accepts a path; both use the managed worktree directory. This proof exercises that supported handoff path. The agent ran pwd but was instructed to keep its absolute output private.

Scenarios were tried twice before this manual run. The first attempt matched an offscreen notification instead of the thread; the second expected a link absent from the CLI response. Neither attempt was used as proof.

AI-assisted; verified with the tests and tools listed above.