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phishark-git

PhiShark Playwright MCP

by phishark-git

browser_snapshot

Read-only

Capture an accessible snapshot of the current page to retrieve element properties, bounding boxes, and tree structure, providing detailed analysis beyond a screenshot.

Instructions

Capture accessibility snapshot of the current page, this is better than screenshot

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
boxesNoInclude each element's bounding box as [box=x,y,width,height] in the snapshot. Coordinates are viewport-relative, in CSS pixels (Element.getBoundingClientRect)
depthNoLimit the depth of the snapshot tree
targetNoExact target element reference from the page snapshot, or a unique element selector
filenameNoSave snapshot to markdown file instead of returning it in the response.

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

B3.3/5.0
Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is clear. The description adds 'capture' but no further behavioral detail beyond what annotations convey.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single concise sentence. The phrase 'this is better than screenshot' adds some comparative value but could be considered slightly extraneous.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

There is no output schema and the description does not explain what format the snapshot takes, how parameters like depth or target affect the result, or what kind of accessibility information is included. This leaves important context missing for an agent deciding whether and how to call the tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema covers all 4 parameters with descriptions, so the baseline is 3. The description does not add any additional parameter meaning or usage notes beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a clear action ('capture') and object ('accessibility snapshot of the current page'), and distinguishes itself from screenshot with a comparative remark, though 'better than screenshot' is somewhat vague.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives minimal guidance by saying 'better than screenshot', but does not explicitly state when to use this tool over alternatives like browser_evaluate or browser_console_messages, nor when not to use it.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.