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derive-client

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. Use when asked to "derive a client", "build a CLI for <site>", "reverse engineer this site's API", "record network requests", "turn this site into an API", or when the same site will be automated repeatedly and direct HTTP calls would beat driving the browser every time.

77

Quality

98%

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SecuritybySnyk

Low

Low-risk findings worth noting

SKILL.md
Quality
Evals
Security

Quality

Content

96%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A strong, dense skill body: executable commands, an explicit sequenced workflow with real verification, and no over-explanation. The only gap is progressive disclosure — the inline jq recipes and failure table could be lifted into reference files to trim the overview.

Suggestions

Move the detailed jq query recipes and the Verify failure table into a reference file (e.g. references/har-queries.md) and link to it from the body, keeping SKILL.md as a lean overview.

Consider extracting auth/cookie extraction specifics into a short reference so step 3 stays scannable.

DimensionReasoningScore

Conciseness

Lean and efficient: assumes Claude knows what HAR files and jq are, omits no padding, and every section delivers executable guidance; the brief intro framing earns its place by establishing when the skill applies.

5 / 5

Actionability

Fully executable, copy-paste-ready commands (agent-browser har start/stop, jq queries, cookies export) plus a symptom/cause/fix table covering the common failure cases.

5 / 5

Workflow Clarity

A clearly numbered 5-step workflow (Record → Identify → Extract → Generate → Verify) with an explicit Verify validation step and feedback loops mapping symptoms to fixes, satisfying the validation requirement for batch/live operations.

5 / 5

Progressive Disclosure

Well-organized into clear sections and self-contained, but as a single ~80-line file it does not split detail (jq recipes, failure table) into one-level-deep reference files, so it stops short of the top anchor.

4 / 5

Total

19

/

20

Passed

Description

100%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

An exemplary description: concrete capabilities, explicit trigger guidance, third-person voice, and a distinct niche with minimal conflict risk. Every dimension lands at the top anchor.

DimensionReasoningScore

Specificity

Lists multiple concrete actions — 'recording browser traffic into a HAR file' and 'generate a standalone client or CLI that calls the endpoints directly' — covering the full what comprehensively.

5 / 5

Completeness

Explicitly answers both what (record HAR traffic → generate direct-call client/CLI) and when (concrete 'Use when...' clause with multiple trigger phrases plus a repetition-based heuristic).

5 / 5

Trigger Term Quality

Comprehensive natural trigger phrases users would actually say: 'derive a client', 'build a CLI for <site>', 'reverse engineer this site's API', 'record network requests', 'turn this site into an API'.

5 / 5

Distinctiveness Conflict Risk

Occupies a clear niche (HAR recording → API client derivation) with distinctive triggers that are unlikely to fire for unrelated skills.

5 / 5

Total

20

/

20

Passed

Validation

93%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

allowed_tools_field

'allowed-tools' contains unusual tool name(s)

Warning

Total

15

/

16

Passed

Repository
vercel-labs/agent-browser
Reviewed

Table of Contents

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