browser-mcp

browser_screenshot

Take a PNG screenshot of the browser page to verify UI state. Save it to a specific path, downscale large images, or capture the full page as needed.

Instructions

Capture a PNG screenshot. If path is omitted, a temp file is used. Set max_dim to downscale results larger than that dimension.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "browser_screenshot"
  }
}

Input Schema

Name	Required	Description	Default
`full`	No
`path`	No
`max_dim`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Sep 18, 2026

TDQS

B3.2/5.0

Behavior3/5

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

With no annotations, the description carries the behavioral burden and does add useful detail: the output is a PNG, a temp file is used when `path` is omitted, and `max_dim` downscales large results. However, it omits what `full` does, how the temp file path is returned, and whether the page must be loaded, so transparency is only partial.

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

Conciseness5/5

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

The description is two sentences with no filler, front-loads the core action, and every sentence contributes useful information.

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 no annotations, so the description must explain return/behavior context. It does not clarify the `full` parameter, how the agent learns the temp file path, or what a successful call returns, leaving important operational details unspecified.

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 coverage is 0%, so the description must compensate. It explains `path` and `max_dim`, but leaves `full` completely undocumented. This is meaningful but incomplete parameter guidance.

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?

The description clearly states the action and resource: 'Capture a PNG screenshot.' This is specific enough to identify the tool's purpose among the browser_* siblings, though it does not explicitly contrast itself with other tools.

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

Usage Guidelines2/5

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

There is no guidance on when to use this tool versus alternatives, nor any exclusions or prerequisites. The description focuses on parameter behavior rather than selection context, so an agent receives no help deciding when screenshotting is appropriate.

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