capabilities

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

With no annotations and no parameters, the only behavioral facts the agent needs are scope and safety, and 'public aggregate' usefully signals that results are anonymized/aggregated rather than raw records. It does not, however, state that the call is read-only, whether the coverage counts are per-domain, or how current the snapshot is.

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?

A single compact sentence with the payload front-loaded and no filler. It is slightly cryptic in the '+ coverage counts' phrasing, which is terse enough to be ambiguous, but there is no waste to cut.

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 must carry the return-value burden, and it only partially does: the agent knows it gets capability info and coverage counts but not the shape, granularity (per-domain vs. global), or freshness of those counts. Adequate for a trivial nullary tool, but thin for a discovery call an agent would use to plan.

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 no parameter semantics to document; the baseline for a nullary tool is 4. The description does not contradict anything in 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?

The description says it reports what DeepMap can answer plus coverage counts, which is more than a pure restatement of the name 'capabilities,' but it uses no concrete verb+resource pairing and does not distinguish itself from the domain siblings. An agent can infer it is a meta/discovery tool, but only by elimination.

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 call this versus the domain tools (water_availability, seismic_hazard, etc.) or the verification tools. The natural use case — checking available coverage before querying a domain — must be inferred entirely by the agent.

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