Environment for every capture: Linux Chromium browser, web development app compiled by Vite from each isolated checkout, 1280x800 CSS viewport, dark theme. Each server used its own database created with T3CODE_DEV_SEED=0. No live database was copied. Provider: the included synthetic image-capable ACP agent; its deterministic acknowledgement passes through the real provider adapter, turn orchestration, fork, delete, cleanup worker, asset endpoint and client.

Base: 43915a4064b341cd040f24c1b906d87222e403de
Head: 0917124ec702e43f44995b929dac569f79e14b8c

Both sides: attach diagram.png and notes.txt, send the same acknowledgement prompt, wait for the response, Fork from this response, return to the source, send notes.txt again after the fork point, delete the source, reload the fork, try its image and open its text attachment, then delete the final fork. The base image has no preview control after it fails; clicking its filename placeholder does nothing. The driver follows that unavailable state without changing the reproduction.

Observed base: image placeholder; text viewer says Attachment was not found; all three files removed at source deletion.
Observed head: full image preview and readable text; source-only text removed at source deletion; inherited image and text retained until final fork deletion, then removed. file-inventory.json records read-only inventories from the real server's attachment directory at each milestone.

before.mp4 and after.mp4 are the same driver executed on both sides, normal playback speed. Only the environment name is visibly redacted in the brief fork details panel and the final empty state; the file inventory confirms cleanup completion. The comparison stills are from the initial manual run of the same sequence. Each still was compared byte-for-byte with a second browser screenshot taken more than 500ms later, and was opened for visual inspection. Recordings were opened as contact sheets and inspected at full size around attachment previews and redaction.

The bundled Replay provider advertises image:false. The included synthetic agent advertises image:true and returns the same acknowledgement each time; no product code was changed. No production model/provider behavior is claimed.

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