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

With readOnlyHint=true and openWorldHint=false already covering the safety profile, the description adds the return shape (slug, name, municipality, region), which matters because there is no output schema. It omits list size, ordering, or pagination behavior for a 'all beaches' result.

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 what the tool returns, followed by the downstream usage hint. No filler.

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 zero-required-parameter read-only list with no output schema, the description covers purpose, returned fields, and next step. Only the omission of result-size/ordering behavior keeps it from being fully complete.

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 single region parameter is documented with an enum and 'Omit for all.' The description never mentions the region filter, so it adds nothing beyond the schema; baseline 3 applies.

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 resource ('All beaches covered by the site') plus the exact fields returned, so an agent knows it is an enumeration endpoint. It does not differentiate itself from the sibling best_beaches_now, which also surfaces beaches, so it falls short of a 5.

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?

'Use a slug with get_beach_guide or get_conditions' tells the agent this is the slug-discovery step that feeds other tools, which is real routing guidance. It gives no explicit exclusion against best_beaches_now, so the alternative case is only implied.

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