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

Annotations already declare readOnly, idempotent, non-destructive, open-world behavior, so the safety profile is covered. The description adds value by disclosing the return payload (station id, coordinates, site type, result count) and the data provenance (USGS/EPA NWIS+STORET+STEWARDS). It does not mention pagination behavior or the default/max limit, which are relevant for a tool with an unrequired limit param.

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?

Three dense sentences, front-loaded with the resource and followed by the routing guidance and provenance. Efficient overall, though the parenthetical source list is slight padding.

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 read-only, open-world, 8-optional-param discovery tool with a fully documented schema, the description supplies the essentials: what it finds, how to use it, what it returns, and where the data comes from. Only minor gaps remain around pagination and its relationship to the near-point sibling.

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%, so every one of the 8 parameters is already documented with format examples (FIPS codes, bbox order, HUC wildcards). The description only restates the search axes without adding syntax or format detail, which is the correct baseline when the schema carries the load.

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+resource (find water-quality monitoring stations) and enumerates the search dimensions (state, county, HUC, bbox, organization). Names the sibling wqp_get_results explicitly as the downstream consumer, distinguishing this discovery tool from its siblings.

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?

Declares itself 'AUTHORITATIVE for "where is water sampled near X"' and explains the handoff to wqp_get_results via the returned station id. It does not, however, contrast itself with wqp_results_near_point, which could plausibly be used for spatial queries — an omission given that sibling exists.

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