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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), so the description earns credit for adding that data is published rather than live and that responses carry source/freshness metadata. The instruction to verify operating details with the facility is a genuine operational caveat. It stops short of describing result limits or freshness semantics.

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?

Purpose and filter modes are front-loaded, which is good. But the bridge sentence is irrelevant to piers and the 'Units: ft, kt, s, F, mi; directions FROM' line is cryptic boilerplate that a caller cannot act on, so not every sentence earns its place.

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, no annotations gap, but 0% schema coverage and a nested object parameter, the description should do more: it omits the limit parameter and any sense of result shape or paging. It does cover units, metadata return, and the published-vs-live caveat, so it is adequate but incomplete.

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 parameter meaning; it partially does by defining 'q' as a name search and 'bbox' as west,south,east,north. It never mentions the nested 'limit' parameter (default 20, max 100), leaving a real gap at low coverage.

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 ('Search') and resource ('published piers') plus the two filter modes (name or west,south,east,north bbox), which lets an agent distinguish it from find_marinas, find_anchorages, and the other find_* siblings. However, the sentence 'Bridge data is published, not a live clearance calculation' is off-topic for a piers tool and reads like boilerplate borrowed from a bridge tool, which blurs the stated purpose.

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 only guidance is a caveat to 'Verify access and operating details with the facility,' which is a disclaimer rather than usage routing. Nothing says when to pick find_piers over find_marinas, find_fuel_docks, or list_bridges, and no prerequisites or exclusions are given.

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