get_vessel_eta

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

With no annotations provided, the description carries full burden but adds nothing beyond the name's implication. It does not disclose return format, units, calculation basis, failure scenarios, or any other behavioral trait. It is effectively a tautology of the tool name.

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?

A single sentence with no filler. The core purpose is stated clearly and immediately with minimal words.

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?

Despite the tool's apparent simplicity, there is no output schema and no annotation to compensate. The description leaves the agent without information about what the ETA response looks like, whether units are hours/dates, or how it differs from related position/port tools. This is too sparse for reliable tool selection and invocation.

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 does not add parameter details, but the schema already documents both vesselId and idType well, including the enum values and defaults.

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 uses a specific verb 'Get' with a precise resource 'estimated time of arrival for a vessel'. This directly differentiates it from sibling tools like get_vessel_position or get_vessel_emissions by focusing on ETA.

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?

No guidance is given on when to use this tool versus alternatives. Sibling tools like get_vessel_position and get_vessel_emissions are not mentioned, nor are any exclusions or contextual triggers provided.

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