Browser MCP Server

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

No annotations are provided, so the description carries full burden. It mentions what metrics are retrieved but fails to disclose behavioral traits such as whether this requires an active browser session, if it's read-only, potential latency, or error conditions. The reference to 'browser_docs' suggests additional info but isn't sufficient for transparency.

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 concise and front-loaded, stating the core purpose in a single sentence with specific metrics listed. The reference to 'browser_docs' is brief but adds value. It avoids unnecessary elaboration, though it could be slightly more structured.

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 0 parameters and no output schema, the description is moderately complete for a simple retrieval tool, but lacks details on return format, error handling, or dependencies. Without annotations, it should provide more behavioral context to be fully adequate for an AI agent.

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 param details, which is appropriate, but it could have mentioned if any implicit context (e.g., current page) is required. Baseline is high due to no parameters.

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 tool's purpose with specific verbs ('Get') and resources ('web vitals and navigation timing'), listing concrete metrics like FCP, LCP, CLS, and TTFB. It distinguishes from siblings by focusing on performance metrics, though it doesn't explicitly contrast with similar tools like 'browser_perf_get_metrics'.

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 implies usage for retrieving performance data, with a reference to 'browser_docs' for more details, but lacks explicit guidance on when to use this tool versus alternatives like 'browser_perf_get_metrics' or other browser tools. It provides some context but no clear exclusions or comparisons.

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