get_performance_metrics

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

Without annotations, the description carries full burden. It states the output is in JSON format and describes the nature of the data (aggregate, system-wide). It implies a read operation, but could explicitly say 'read-only' and mention any limitations like time range.

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 sentences, both front-loaded: first sentence states purpose, second provides usage guidance. No unnecessary words.

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?

With no output schema, the description should explain the return structure more. It only says 'in JSON format' and 'aggregate performance metrics', which is vague. For a complete understanding, the agent would benefit from knowing what specific metrics are included (e.g., latency, error rate).

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?

Schema coverage is 100%, so baseline is 3. The description adds no extra meaning to the parameters beyond what is already in the input schema. It does not explain how 'ts', 'm', 'env', 's' relate to the aggregate metrics.

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 verb 'Retrieve' and the resource 'aggregate performance metrics and system-wide statistics'. It distinguishes the tool from its sibling 'get_traces' by mentioning it is for high-level overview.

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 says 'Use for monitoring overall application health, trends, and high-level performance overview' and provides an alternative: 'use get_traces for detailed individual request analysis'. This gives clear guidance on when to use this tool.

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