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Reverse-engineer a website's internal API by recording browser traffic into a HAR file, then generate a standalone client or CLI that calls the endpoints directly, with no browser needed after the first recording.
Passed 21 of 22 test cases with the skill, and 12 of 22 without it.
and 9 more in the full report
9 fixed12 passed either way1 still failing0 broke
Tokens, turns and time describe resource use, not a dollar price.
One of 9 test cases the skill fixed. Same model, same prompt, with and without the skill.
By default, the CLI browser agent embeds text response bodies up to 2 MB. What flag must be supplied if binary response bodies like images or zip archives need to be embedded in base64 format?
| Checked | Without skill | With skill |
|---|---|---|
| Identifies `--content all` as the option to capture binary response bodies. | Missed | Passed |
The instructions your model reads when the skill loads.
Driving a browser is the right tool for the first visit and the wrong tool for the hundredth. This skill records a site's network traffic once while you use it, then turns the captured requests into a standalone client (script, CLI, or library) that talks to the site's internal API directly.
The recording alone contains everything needed: agent-browser embeds text response bodies (JSON/HTML/JS) in the HAR by default, so endpoint shapes can be studied offline after the browser is closed.
1. Record Start HAR capture, drive the flows you want in the client
2. Identify Find the real API endpoints among the noise
3. Extract Pull request shapes, response schemas, and auth material
4. Generate Write the client, one function per flow
5. Verify Call every endpoint for real before declaring done
agent-browser network har start # embeds text response bodies by default
# ... drive the site: search, open a detail page, paginate, etc. ...
agent-browser network har stop /tmp/site.har
--content all embeds binary bodies too (base64); --content none disables embedding. Per-body cap is 2 MB.While the session is still open, agent-browser network requests and network request <id> give the same data interactively — but only the HAR survives navigation and browser close, so prefer it for anything multi-page.
Query the HAR with jq:
# All JSON API calls: method, URL, status
jq -r '.log.entries[]
| select(.response.content.mimeType | test("json"))
| "\(.request.method) \(.response.status) \(.request.url)"' /tmp/site.har
test cases passed, vs 12 / 22 without
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