Browser MCP Server

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

No annotations are provided, so the description carries the full burden. It states what metrics are retrieved but doesn't disclose behavioral traits like whether this requires an active browser session, if it's read-only/destructive, latency expectations, or error conditions. The mention of 'browser_docs' suggests additional context exists elsewhere, but the description itself is insufficient for behavioral understanding.

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 a single, efficient sentence that front-loads the core purpose. The parenthetical examples and reference to 'browser_docs' add value without unnecessary elaboration. It could be slightly more structured by separating the reference, but overall it's appropriately concise.

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 no annotations and no output schema, the description is incomplete for a performance metrics tool. It lists metric types but doesn't explain the return format, units, or how to interpret results. The reference to 'browser_docs' implies missing context, but the description alone doesn't provide enough information for effective tool use.

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 appropriately doesn't discuss parameters, maintaining focus on the tool's purpose. A baseline of 4 is appropriate for zero-parameter tools when the description doesn't incorrectly mention 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: 'Get runtime performance metrics (DOM nodes, event listeners, JS heap)'. It specifies the verb ('Get') and the resource ('runtime performance metrics') with concrete examples. However, it doesn't explicitly differentiate from sibling tools like 'browser_perf_get_heap_usage' or 'browser_perf_get_performance_metrics', which appear to be related performance tools.

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 no guidance on when to use this tool versus alternatives. It mentions '(see browser_docs)' which might contain usage information, but the description itself lacks explicit when/when-not instructions or references to sibling tools. This leaves the agent without clear usage context.

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