Record Browser Gif

Record Browser GIF

Produce a short, truthful UI demonstration as a local GIF, and — only when the task includes attaching it to a pull request — publish it through the assets-branch workflow at the end of this skill. Drive interaction with the repository's browser-control skill when available, otherwise the repository-declared Playwright dependency, and encode with the bundled encoder for repeatable timing, dimensions, and size.

Every GUI pull request includes a GIF

A pull request that changes product-user-visible GUI behavior MUST include a demonstration GIF recorded with this skill and embedded in the pull request body via the assets-branch workflow.

The recording itself is part of the evidence: use a real server booted from that pull request's branch tree, real credentials, and real data flow (real model rounds where the app is model-backed). Never substitute fixture queries, mock transports, synthetic event injection, or test-only hooks unless the user explicitly asked for a fixture recording. Next to the embed, state the exact demonstrated commit SHA, the tree and origin that served it, any mode flags or browser-state exceptions, and whether a real model round ran, so reviewers know exactly what the recording proves.

Keep recording separate from publication

• Recording produces frame images and one local .gif artifact only; it never mutates remote state.
• Publication — pushing the GIF to an assets branch and embedding it in a pull request body — is the separate final step, performed only when the task includes attaching the GIF to a pull request. It never touches the pull request's own branch.
• Preserve the requested recording conditions. A real-server or real-credential demo must not use fixture queries, mock transports, synthetic event injection, or test-only hooks. If credentials or the server are unavailable, report that limitation instead of substituting a fixture.
• Never read or expose credential values. Use the application's normal configuration path and a benign demonstration prompt.

Stage the application

A GIF for a specific pull request demonstrates that pull request's tree, so stage per pull request:

1. Require a clean worktree, record its exact commit with git rev-parse HEAD, then build that recorded tree with the repository's build commands for the recorded tree. A GIF recorded against another commit's build misattributes the evidence.
2. Boot one server per port from that tree with the application's fresh state roots, workspace, and session state. Give the browser a fresh isolated context or profile as well; if the browser workflow cannot create one, clear that origin's cookies and site storage before navigation so persisted client state cannot affect the evidence. Source credentials through the application's normal configuration path; never echo them.
3. Treat one storyboard as one evidence run: every published frame comes from that server and those state roots, workspace, session, and data-flow scenario run. If capture automation fails, discard its frames and rerun from fresh roots; never splice frames from separate runs.
4. When switching between pull requests, stop the old server by PID or an exact match on its command line. A broad pkill -f pattern can match and kill the shell that launched it — including your own.

Record the flow

1. Invoke the repository's browser-control skill when available, and follow its setup, interaction, and cleanup instructions. Use the user's existing browser state only when requested or required; state that exception in the provenance and do not claim fresh client state. If browser control is unavailable, use the repository-declared Playwright dependency in an isolated headless browser; do not install another driver or launch the user's browser. State that fallback in the provenance.
2. Before recording, identify the exact origin, whether the app is built or in development, the transport, and any fixture or mock mode. Record only claims that the observed setup supports.
3. When a production default opens a native operating-system surface that headless automation cannot drive, select an official browser-operable production backend through the application's normal configuration. State the override in the provenance; a fixture, mock transport, or test-only hook is not an acceptable substitute.
4. Choose three to six states that tell one story, such as typed, running, settled, and detail. Prefer semantic state changes over continuous capture; omit loading churn that does not help the viewer.
5. Keep one viewport and crop for every frame, and name frames lexically: 00-initial.png, 01-typed.png, and so on.
6. Store frames under the repository's gitignored browser-tool screenshots directory (for example .playwright-mcp/), since browser-tool screenshots can only be written under the tool's allowed roots and relative filenames resolve against the repository root. Create the frame subdirectory first (mkdir -p <screenshots-dir>/gif-frames-<label>); writing into a missing directory fails with ENOENT at capture time.
7. Before each screenshot, wait for a concrete UI condition such as a unique label, enabled control, changed document title, or completed response. Require the locator to resolve exactly one element; for Playwright accessible-name locators, use exact: true when equality is intended because descendant text or a prompt echo can otherwise create a false match. Do not use a fixed delay as proof that the application reached the state.
8. Make completion predicates match an exact-text element — for example, an element whose trimmed text equals the expected reply — never a substring check such as body.textContent.includes(...), which the echo of the user's own prompt also satisfies.
9. When the claim involves a tool call, rejection, or recovery, include a detail or trajectory frame that shows the tool identity, status or stable error code, and the downstream result. A chat-only outcome does not prove why the tool path behaved that way.
10. Capture a transient state (spinner, running row) by driving a slow foreground operation — for example, a sleep 15 bash command — and polling a concrete DOM marker (a data-* attribute) inside one browser-script call that also takes the screenshot. State polled across separate tool calls is lost, because the turn settles between calls.
11. Engineer the prompt so the state you need actually occurs: instruct the model to wait in the foreground when it would otherwise background a slow command, and give it a settle sentinel such as "reply with the single word done" to anchor the completion predicate.
12. Capture no secrets, personal data, unrelated tabs, or transient notifications. Stop any unnecessarily long real-server run after the demonstrated state is visible.

Use the browser's own screenshot API. When it returns image bytes, save those bytes directly; the encoder detects image content independently of the filename extension.

Encode the GIF

Require python3, ffmpeg, and ffprobe. If either media binary is missing, report the dependency instead of installing software without authorization.

Export GIF_SKILL_DIR as this skill's absolute directory on its own line before the python command — an inline GIF_SKILL_DIR=... python3 "$GIF_SKILL_DIR/..." assignment fails, because the argument expands before the assignment takes effect:

export GIF_SKILL_DIR=/absolute/path/to/this/skill
python3 "$GIF_SKILL_DIR/scripts/encode_gif.py" \
  /absolute/path/to/frames \
  /absolute/path/to/demo.gif \
  --durations 1.5,1.5,1.5,3.5 \
  --fps 10 \
  --max-width 1200 \
  --colors 128

One duration applies to every frame; otherwise provide one comma-separated positive duration per frame, holding the final settled state longest. The encoder rejects fewer than two frames, mismatched dimensions or durations, invalid limits, accidental overwrite, unexpected duration, and output above --max-bytes.

For a large artifact, reduce --max-width first, then --colors or --fps; retain readable text and the final state long enough to inspect. Use --force only after resolving the exact output path.

Verify the artifact

1. Read the encoder's JSON summary and confirm the output path, source and encoded frame counts, dimensions, duration, and byte size.
2. Visually read the encoded GIF itself, not only the source frames. Confirm that the transition is legible, the last state is held long enough, and no sensitive content appears. If the viewer renders only the first frame, decode representative frames from the encoded GIF with ffmpeg and inspect those; the pre-encode screenshots do not prove the encoded order, palette, or final hold.
3. Run git status --short and confirm frames and the artifact landed only under ignored paths.
4. Return the absolute GIF path, render it when the client supports local media, and state whether the recording used a real server, fixture, or another transport. When the task does not include attaching the GIF to a pull request, stop here.

Publish to an assets branch

Perform this step only when the task includes attaching the GIF to a pull request.

Never commit a GIF to the pull request's own branch or any branch that merges into a long-lived branch: binary media committed there bloats the repository history for every future clone. GIFs live on a dedicated orphan assets branch — a branch with no parent commit and nothing but media — and one assets branch serves a whole pull request series (named <series>-assets; list existing ones with git ls-remote --heads origin '*assets*').

Before either workflow below pushes, verify that the assets branch contains media only and that the staged GIF's checksum matches the verified local artifact.

For an existing assets branch, work in a shallow single-branch scratch clone so the publication cannot touch your working tree:

git clone --branch <assets-branch> --single-branch --depth 1 <repo-url> /tmp/assets-checkout
cp /absolute/path/to/demo.gif /tmp/assets-checkout/<name>.gif
cd /tmp/assets-checkout
git add <name>.gif
git commit -m "assets: <what it shows> gif (#<pr>)"
git push origin <assets-branch>

For a new series, make a fresh shallow scratch clone (git clone --depth 1 <repo-url> /tmp/assets-checkout), create the orphan branch with git switch --orphan <assets-branch>, then add the GIF, commit, and push the same way.

After pushing, use authenticated GitHub API or raw requests to confirm the remote path, byte size, checksum, 200 response, and image/gif content type. An anonymous 404 does not disprove a private-repository asset; authenticate the verification instead. This proves the repository-member review path, not public availability.

Immediately before editing the pull-request body, re-read its live head and compare it with the commit recorded next to the GIF. Stop and re-record when it moved. After the edit, re-read the live head and require it to remain at that recorded commit. Separately, render the body through GitHub's Markdown API and confirm that the expected <img> is present.

Embed the GIF in the pull request body with the raw blob URL; the ?raw=true suffix is required, because the plain blob URL renders GitHub's file page instead of the image:

![<alt text>](https://github.com/<owner>/<repo>/blob/<assets-branch>/<name>.gif?raw=true)

Never delete or rewrite an assets branch, and never force-push it: merged pull request bodies reference its URLs forever. Append new commits only.