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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real value by disclosing the return contents, which matters because no output schema exists, and it flags that load-time validation issues are surfaced rather than silently ignored.

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 short sentences, front-loaded with the primary content list and followed by the one unusual behavior (load-time validation issues). No filler and nothing restated from structured fields beyond necessity.

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 no-arg, read-only stats tool with no output schema, the description sufficiently describes what comes back, including the breakdown dimensions. It stops short of explaining scope (whole corpus vs. a suite) or formatting, which are the only remaining ambiguities.

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 tool takes zero parameters, so there is nothing to document in the description; the baseline for a 0-param tool is 4. Schema coverage is 100% and the empty object is self-explanatory.

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 resource and enumerates the concrete outputs (total patterns, reviewed %, per-suite/per-confidence breakdown, validation issue count), so an agent knows exactly what this tool returns. It does not differentiate itself from siblings, but the siblings (search_patterns, list_requirements, etc.) are retrieval tools rather than competing stats providers, so differentiation is barely needed.

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?

No explicit when-to-use, when-not-to-use, or alternative guidance is given. The agent must infer that this is the tool to call for coverage reporting, and nothing states when to prefer it over, say, list_unreviewed for review-status questions.

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