Playwright MCP Server

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

Annotations already indicate destructiveHint=true and readOnlyHint=false, so the agent knows this is a destructive write operation. The description adds useful context about installing based on config and error handling, but it doesn't disclose additional behavioral traits like installation time, success/failure responses, or system requirements beyond what annotations provide.

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 two sentences that are front-loaded and waste-free: the first states the purpose, and the second provides usage guidance. Every sentence adds value, making it highly concise and well-structured for quick understanding.

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 complexity (a destructive installation operation), annotations cover safety (destructiveHint=true), but there's no output schema. The description mentions config-based installation and error handling, but it lacks details on what happens after installation (e.g., success confirmation, browser launch) or potential side effects, leaving some gaps in completeness.

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 0 parameters with 100% coverage, so no parameter documentation is needed. The description doesn't add parameter information, which is appropriate here, but it could briefly mention that no inputs are required, earning a baseline score of 4 for adequate handling in a parameterless tool.

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 ('Install') and resource ('the browser specified in the config'), making the purpose understandable. However, it doesn't explicitly differentiate from sibling tools like 'browser_navigate' or 'browser_close', which are unrelated to installation, so it doesn't fully distinguish from all siblings.

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 clear context for when to use the tool: 'if you get an error about the browser not being installed.' This gives a specific trigger condition. However, it doesn't mention when not to use it or explicitly name alternatives, such as checking browser status first, which would make it more comprehensive.

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