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core

Core agent-browser usage guide. Read this before running any agent-browser commands. Covers the snapshot-and-ref workflow, navigating pages, interacting with elements (click, fill, type, select), extracting text and data, taking screenshots, managing tabs, handling forms and auth, waiting for content, running multiple browser sessions in parallel, and troubleshooting common failures. Use when the user asks to interact with a website, fill a form, click something, extract data, take a screenshot, log into a site, test a web app, or automate any browser task.

72

Quality

91%

Does it follow best practices?

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SecuritybySnyk

Low

Low-risk findings worth noting

SKILL.md
Quality
Evals
Security

Quality

Content

81%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 highly actionable, well-sequenced CLI guide with real error-recovery loops and a sound reference structure. Its main weakness is length: duplicated WebMCP prose and inlined reference-grade detail (dashboard, read flags) bloat the overview, and one cited bundle path (templates/*) does not exist.

Suggestions

Deduplicate the WebMCP paragraphs: keep the discovery/security details in one place (e.g. a references/webmcp.md or the core-loop section) and have the Troubleshooting entry reference it instead of repeating ~80% of the same text.

Move reference-grade configuration detail — dashboard allowed-origins/token behavior, the read command's flag-by-flag semantics, and idle-timeout/restore-save policy specifics — into references/*.md files, leaving SKILL.md as a lean overview with one example each.

Fix the dangling 'templates/*' citation in the 'Full reference' section: either ship the starter shell scripts in the bundle or remove the bullet until they exist.

DimensionReasoningScore

Conciseness

The body contains no explanations of concepts Claude already knows — every sentence is agent-browser-specific — but at ~580 lines it is noticeably longer than an overview needs to be. The WebMCP announcement/security paragraph appears nearly verbatim in both 'The core loop' and 'Troubleshooting', and the 'read' flag enumeration plus the dashboard origin/token paragraphs are dense reference-grade prose that could be tightened or moved to references. This fits 'mostly efficient but could be tightened' rather than the noticeably-padded 2 anchor.

3 / 5

Actionability

Nearly every section is copy-paste-ready bash: a working quickstart, a login workflow with concrete refs, semantic-locator and CSS fallbacks, a wait-strategy menu with exact commands, heredoc-based eval examples, and doctor diagnosis commands. Specific examples cover the common cases, matching the fully-executable 5 anchor.

5 / 5

Workflow Clarity

The core loop is explicitly sequenced (open → snapshot -i → act on refs → re-snapshot), the waiting section prescribes a concrete post-action checkpoint ('After any page-changing action, pick one'), and the troubleshooting section is a set of error-recovery feedback loops (e.g. 'Ref not found' → re-snapshot → use new refs). Destructive repairs are gated behind 'doctor --fix', so the destructive-operation cap does not apply.

5 / 5

Progressive Disclosure

References are one level deep, clearly signaled, and all ten cited references/*.md files exist in the bundle. However, reference-grade material is inlined in SKILL.md (dashboard origin/token configuration, WebMCP discovery details), and 'templates/*' is cited under 'Full reference' with no templates directory present in the bundle — minor organization gaps that keep this below the 5 anchor.

4 / 5

Total

17

/

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: third-person, concrete capability list, explicit and natural trigger phrases, and a distinct tool-specific niche. All four dimensions sit at the top anchors.

DimensionReasoningScore

Specificity

The description lists multiple concrete, tool-specific actions — 'snapshot-and-ref workflow, navigating pages, interacting with elements (click, fill, type, select), extracting text and data, taking screenshots, managing tabs, handling forms and auth, waiting for content, running multiple browser sessions in parallel, and troubleshooting common failures' — with comprehensive coverage and no vague filler. It is written in third person ('Covers...'), matching the top anchor.

5 / 5

Completeness

It explicitly answers both questions: 'what' via the 'Covers...' capability list and 'when' via the concrete 'Use when the user asks to...' trigger list — exactly the pattern of the 5 anchor example. Neither component is missing or merely implied.

5 / 5

Trigger Term Quality

'Use when the user asks to interact with a website, fill a form, click something, extract data, take a screenshot, log into a site, test a web app, or automate any browser task' provides eight natural user phrasings with synonym-level variation. This fits the comprehensive 5 anchor better than 4, though 'scrape'/'web scraping' is a notable near-miss covered only indirectly by 'extract data'.

5 / 5

Distinctiveness Conflict Risk

'Core agent-browser usage guide. Read this before running any agent-browser commands' names a specific tool with a clear niche, and specialized sibling domains (Electron, Slack, QA) are delegated elsewhere. Triggers are browser-automation specific, so overlap with unrelated skills is minimal.

5 / 5

Total

20

/

20

Passed

Validation

87%

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

Validation — 14 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

skill_md_line_count

SKILL.md is long (583 lines); consider splitting into references/ and linking

Warning

allowed_tools_field

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

Warning

Total

14

/

16

Passed

Repository

vercel-labs/agent-browser

Path

skill-data/core/SKILL.md

Reviewed

Table of Contents

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