Browser MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the action ('Resize') but doesn't mention side effects (e.g., whether it affects page content, requires specific browser states, or has limitations like minimum/maximum sizes). The reference to 'browser_docs' suggests additional documentation exists, but the description itself lacks critical behavioral details for safe invocation.

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

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

The description is brief and front-loaded with the core purpose, followed by a parenthetical note on usefulness and a reference to documentation. It avoids redundancy and wastes no words, though the parentheticals slightly reduce structural clarity. Overall, it's efficient but could be more streamlined.

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

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

Given the tool's moderate complexity (a mutation operation with two parameters), no annotations, and no output schema, the description is minimally adequate. It states what the tool does but lacks details on behavior, error conditions, or return values. The reference to 'browser_docs' hints at external completeness, but the description itself leaves gaps in contextual understanding.

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

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

The input schema has 100% description coverage, with clear definitions for 'width' and 'height' as pixels. The description adds no parameter-specific information beyond what the schema provides, such as valid ranges or units. Since the schema does the heavy lifting, the baseline score of 3 is appropriate, as the description doesn't compensate but also doesn't detract.

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

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

The description clearly states the action ('Resize') and target ('the browser window'), with an additional context about its usefulness for testing responsiveness. It distinguishes from siblings like browser_screenshot or browser_navigate by focusing on window dimensions. However, it doesn't explicitly differentiate from all window-related tools (e.g., browser_focus or browser_switch_page), which prevents a perfect score.

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

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

The description provides minimal guidance by mentioning it's 'useful for testing responsiveness', which implies a testing context, but lacks explicit when-to-use instructions, prerequisites, or alternatives. No comparison to sibling tools is made, and it doesn't specify scenarios where this tool should be preferred over others, leaving the agent with insufficient direction.

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