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

Annotations already declare readOnly, idempotent, non-destructive, open-world. The description goes beyond them by disclosing the returned fields (port codes, coordinates, measures, coverage, pagination, provenance) and the inbound-only scope constraint. It doesn't cover rate limits or auth given the self-hosted snapshot, but it adds meaningful context over the structured hints.

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 front-loaded sentences: purpose/source, return payload, and use cases with exclusions. The return-field enumeration is a touch long but each element is informative. Overall tight with 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?

There is no output schema, so the description usefully compensates by listing the return fields, coverage, pagination, and provenance. Combined with annotations covering the safety profile and a fully documented input schema, an agent has nearly everything needed; only filter-combination semantics are left unstated.

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% with per-field descriptions (limit, query, state, border, offset, response_format), so the schema already carries parameter meaning. The description adds only indirect hints via examples ('Laredo', 'Arizona') and doesn't specify query format or how filters combine. Baseline 3 is appropriate.

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 (U.S. land-border ports) with the exact data source, and distinguishes scope with 'Inbound land ports only; not wait times or outbound traffic.' An agent can separate it from the sibling border tools (trend, compare_ports, activity_pack) without opening any schema.

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?

Offers concrete when-to-use triggers in quotes ('find the Laredo border port code', 'which Arizona ports have truck crossings?') and wraps the workflow ('resolve a port before a trend call'), plus an explicit exclusion for wait times and outbound traffic. It stops short of naming the actual sibling alternatives (e.g., bts_transport_compare_ports), so routing is implied rather than fully explicit.

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