browser-mcp

browser_cdp

Execute raw Chrome DevTools Protocol methods directly, passing parameters as keyword arguments to control browser behavior, extract UI data, or intercept network traffic.

Instructions

Call a raw Chrome DevTools Protocol method. params are passed as kwargs.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

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

Input Schema

Name	Required	Description	Default
`method`	Yes
`params`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Sep 18, 2026

TDQS

B3.2/5.0

Behavior2/5

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

Annotations are absent, so the description carries the full burden. It discloses the action ('Call') but not side effects, validation behavior, possible errors, authentication needs, or response format. Calling a raw CDP method can mutate browser state, but the description does not warn about this.

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?

Two concise sentences with no filler. The main purpose is front-loaded, and the note about `params` as kwargs is directly relevant and compact.

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?

Although the input schema is simple, the absence of annotations, output schema, and usage context makes the description thin. It does not explain return values, errors, or when this raw tool should be preferred over the dedicated sibling tools, so the agent is left under-informed for correct invocation.

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 adds one useful semantic detail: `params` are passed as keyword arguments. However, it provides no guidance on `method` values, how to construct params, or the relationship between the two, leaving meaningful gaps.

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

Purpose5/5

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

The description specifies the exact verb ('Call') and resource ('raw Chrome DevTools Protocol method'), and the word 'raw' clearly distinguishes it from the high-level sibling tools like browser_click or browser_navigate. An agent can immediately understand this is a low-level passthrough rather than a convenience operation.

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?

No guidance is given for when to use this tool versus the many provided browser helpers. There is no mention of 'use this when no high-level tool exists' or any warning about when it is inappropriate, leaving the decision entirely to the agent.

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