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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety bar is met. The description adds genuinely useful semantics beyond that: counts are computed live, capability link/signature counts exclude retired records, and the active/retired splits live in the capability tools' metadata.

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 scoping note is well placed and the content is signal-dense, but the first sentence is a single sprawling run-on enumerating every distribution dimension. It is hard to parse and could be structured into bullets or split sentences.

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 carries the return-value burden and does so thoroughly: it names every dimension, the ENT/Warmth Engine Ratio, the derived layers, event-ID range, and methodology version. Only the response's actual shape/format is left implicit.

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?

There are zero parameters, so per the baseline there is nothing for the description to disambiguate at the argument level. It correctly notes 'No parameters', matching the empty schema.

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?

States a specific verb (retrieve) and resource (corpus statistics) and enumerates exactly what is returned — event/CC/actor distributions, ENT/Warmth Engine Ratio, derived layer counts, methodology version. This is unmistakably different from get_metrics or get_methodology.

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 conveys that it takes no parameters and computes live figures, implying it is the 'describe present coverage' tool, but it never states when to prefer it over get_metrics, get_topology, or get_methodology. Usage must be inferred.

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