mcp_usage

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered structurally. The description adds the report's contents but nothing behavioral beyond that — no pagination, refresh cadence, or auth requirements — so it is adequate but not rich.

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?

One sentence, front-loaded with the resource and immediately followed by the returned fields. 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?

An output schema exists, so return values need no explanation, and annotations carry the safety profile. The only real gap is the unexplained 'days' parameter, which leaves the agent guessing at the default lookback semantics.

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 0% and the single 'days' parameter (default 30) is never mentioned in the description. Because coverage is below 50%, the description was expected to compensate for the undocumented window parameter and does not.

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 a specific resource (this MCP server's agent usage) and enumerates the content returned: tool-call counts, error rates, recent questions. That is far more concrete than a tautology, but it never differentiates itself from the many metrics-oriented siblings such as list_metrics or query_metrics.

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?

There is no statement of when to reach for this tool versus the sibling analytics tools, and no prerequisites or exclusions. The agent must infer from the name alone that this reports on MCP/agent traffic rather than product metrics.

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