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

Annotations already declare the safety profile (readOnly, idempotent, non-destructive, openWorld), so the bar is lower, yet the description still adds real context: units (ft, kt, s, F, mi), 'directions FROM', a published-vs-live-data caveat, and that results include source/freshness metadata. This goes beyond what the annotations convey.

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 compact and front-loads the core search capability, but the misplaced 'Bridge data is published, not a live clearance calculation' sentence is irrelevant to anchorages and spends space without earning it.

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?

There is no output schema, and the description compensates by stating that results include source/freshness metadata, satisfying the return-value burden. Combined with the units/direction conventions and the published-data caveat, an agent has enough to call it correctly; the only shortfall is the undocumented limit parameter.

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 0%, so the description must carry the burden. It names the two query modes (name via q, bbox via west,south,east,north), which maps to the q and bbox fields, but the nested query object and the 'limit' parameter (default 20, max 100) are never explained, leaving meaningful gaps.

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 and resource with the query modes: 'Search published anchorages by name or west,south,east,north bbox.' This distinguishes it from siblings like find_marinas, find_beaches, and find_dive_sites. The off-topic 'Bridge data is published' clause muddles the purpose slightly but does not obscure the core operation.

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?

Provides a caveat ('Verify access and operating details with the facility') but no guidance on when to choose find_anchorages over sibling discovery tools such as find_marinas or search_pois, and no exclusions or prerequisites. Usage context is left entirely to inference.

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