browser_perf_get_metrics

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

The description lacks any behavioral disclosure beyond its function. With no annotations, the agent has no information on side effects, prerequisites, or whether the tool is read-only. The brief text does not compensate for missing safety or behavioral context.

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 with one sentence that front-loads the key action and examples. The parenthetical reference to browser_docs adds minimal value but does not detract. It is efficient but somewhat terse.

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?

Despite no output schema, the description provides specific metrics (DOM nodes, event listeners, JS heap) which gives a good sense of the return value. For a parameterless tool, it is fairly complete, though it could mention that these are aggregated runtime metrics.

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?

There are no parameters, so the baseline score is 4 per guidelines. The description does not need to elaborate on parameter meanings, and the schema coverage is 100%.

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 retrieves runtime performance metrics and lists concrete examples (DOM nodes, event listeners, JS heap), making it distinct from sibling tools like browser_perf_get_heap_usage which is more specific. However, it does not explicitly differentiate from browser_perf_get_performance_metrics, which has a similar name.

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?

No guidance is provided on when to use this tool versus alternatives like browser_perf_get_heap_usage or browser_perf_get_performance_metrics. There are no exclusions or context hints for optimal usage.

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