get_service_metrics

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

Annotations already declare read-only, idempotent, and non-destructive. The description adds valuable context by listing the specific metrics returned and suggesting how to interpret them (e.g., 'look for sudden spikes in error_rate or latency_ms following a deployment'), which goes beyond the annotations.

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 three concise sentences: the first states the exact function, the second states the use case, and the third gives an actionable interpretation tip. No filler or redundancy.

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?

The tool has simple parameters and a clear purpose. The description covers the main use and interpretation, but it does not describe the return format or explicitly mention default time range, though the schema handles those details. Overall, it is sufficiently complete for a read-only metrics tool.

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 100% description coverage for both parameters, so the schema already provides full parameter semantics. The description does not add any parameter-specific details beyond what is in the schema, making the baseline 3 appropriate.

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 uses a specific verb 'Retrieves' and clearly identifies the resource: 'time-series performance metrics for a specific service', listing the exact metrics (latency, error rate, CPU, memory, RPS). This distinguishes it from sibling tools like get_recent_deployments or get_service_logs.

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 explicitly advises using it to identify performance degradation trends and correlate with deployments or incidents, providing clear context. However, it does not mention when not to use it or name specific alternatives, so it lacks explicit exclusions.

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