metrics_overview

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 does disclose what data comes back, which is genuinely useful, but it says nothing about read-only semantics, permissions, default window behavior, or cardinality of the top-error-routes list.

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?

Two sentences, front-loaded with the returned fields and followed by the use case. No filler, though the first sentence is a dense enumeration rather than a crisp statement of purpose.

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?

For a two-parameter read tool with full schema coverage and no output schema, the description covers both the returned metrics and the intended use case. The main gap is the absence of routing guidance against the many sibling metrics tools.

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 description coverage is 100%, including the default of 60 minutes and the pointer to list_projects for project_id. The description adds no parameter-level meaning beyond what the schema already states, so the baseline of 3 applies.

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 names the specific contents returned (total requests, error count & rate, average/p95 latency, top error routes) and frames the resource as an overview section of metrics. It is clear what the tool does, but it does not explicitly distinguish itself from close siblings like metrics_summary or metrics_trends.

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?

"Use this for a quick health snapshot focused on request volume and performance" implies the usage context but names no alternatives or exclusions. With seven sibling metrics_* tools in the set, an agent still has to guess why it would pick this over metrics_summary or metrics_levels.

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