Search Ukrainian national vessel registries

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

With no annotations, the description carries the full burden of behavioral disclosure. It does disclose two meaningful behaviors: deterministic ordering with exact registration-number matches first, and that each result includes a web_url for ordering an official excerpt. However, it does not mention pagination behavior, rate limits, or whether the operation is strictly read-only, which could be relevant. The disclosed behaviors are useful but not comprehensive, justifying a 3.

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 two sentences with zero filler. It front-loads the core purpose, then adds the ordering behavior and result link. Every sentence contributes essential information, making it an exemplary model of conciseness.

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?

The tool has 8 parameters (0 required), no output schema, and no annotations, making the description the primary source of context. It covers the basic purpose, ordering logic, and the web_url presence, but it does not explain how filters combine (e.g., AND semantics), the effect of the source parameter, or what other fields appear in results. Given the tool's complexity, the description is adequate but leaves room for interpretation, so a 3 is appropriate.

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 the baseline is 3. The description adds nothing beyond the schema's parameter documentation; it only refers generally to 'free-text query and structured filters.' It does not provide additional context on parameter interaction or format beyond what the schema already states. Therefore, the description meets the baseline but does not elevate it.

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?

The description clearly states the action (search) and the exact resources (Державний судновий реєстр України and Суднова книга України), along with the search method (free-text and structured filters). It also notes the deterministic ordering and the presence of a web_url in results, making the tool's function unambiguous. However, it does not explicitly contrast with sibling tools like lookup_vessel or get_registry_stats, so it falls just short of a perfect score.

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 description implicitly conveys when to use the tool (when searching by free-text or structured filters across these registries), but it does not provide explicit guidance on when not to use it or mention alternatives. For instance, it does not say that lookup_vessel should be used for exact vessel lookups. The usage context is clear but lacks explicit exclusions or comparisons, so it earns a 3.

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