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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so safety and idempotency are covered. The description adds pricing information (free within daily allowance, then $0.001 USDC per call via x402), which is useful behavioral context. However, it does not detail rate limits, pagination, or result ordering, and no output format is described (though an output schema exists).

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 description is two concise sentences, front-loading the core purpose and then adding pricing. Every sentence earns its place with no redundancy or waste.

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 search tool with an output schema and rich annotations, the description covers the essential purpose and usage context. However, it does not mention result limits, pagination, or any constraints on the search (e.g., partial name matching, district vs. site name ambiguity). Given the existence of an output schema, return values need not be explained, but some procedural context is missing.

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%, and the schema already documents both parameters with descriptions. The description mentions 'by name or district' and 'by classification', which maps to the parameters but adds no syntax, format, or enum details beyond the schema (which already lists classification values). Baseline 3 is appropriate when the schema carries parameter semantics.

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 uses a specific verb ('Find') and resource ('bathing waters') and articulates two clear search modes (name/district and classification). This distinguishes it from siblings like bathing-water__near, which would be a geospatial lookup rather than a name/classification search.

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 gives clear positive usage contexts ('Find bathing waters by name or district, and/or by classification') but does not explicitly state when to use this tool versus alternatives such as bathing-water__near. The distinction is implied by the search modes, but no exclusions or alternative mentions are provided.

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