search_metrics

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 discloses what the tool returns (matching metrics with IDs, API endpoints, access tiers, descriptions) and that it is a search operation, implying read-only behavior. It does not detail matching logic (e.g., partial vs exact) or pagination, but for a simple discovery tool this is adequate.

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 concise sentences. It front-loads the action and result, then provides usage guidance. Every sentence adds value with no redundancy or fluff.

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 having no output schema, the description states the return fields (IDs, API endpoints, access tiers, descriptions), covering the essential output. The tool is simple (one parameter), and the description includes purpose, usage context, and output details, making it complete for its complexity.

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 schema already fully describes the 'query' parameter with examples, so the baseline is 3. The description adds meaningful context by stating the search is 'by name or description,' which the schema property does not mention. This enhances parameter understanding beyond the structured schema.

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 function: 'Search available metrics by name or description' and specifies what it returns (IDs, API endpoints, access tiers, descriptions). This distinguishes it from siblings like list_metrics (which likely lists all) and get_metric (which retrieves a specific metric). The verb 'search' is specific and the resource is explicit.

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 a clear usage context: 'Use this to discover which metrics are available before fetching data.' This tells the agent when to use it (as a discovery step) and implies an alternative (fetching data directly). However, it does not explicitly name alternative tools or state when not to use it, so it falls short of a perfect score.

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