Marlo MCP

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

With no annotations provided, the description carries full burden but offers no behavioral insights. It does not disclose whether this is a read-only operation, requires authentication, has rate limits, returns structured data, or involves side effects. The single verb 'Get' implies retrieval but lacks depth on behavior or constraints.

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 extremely concise ('Get vessel details'), which is front-loaded but under-specified rather than efficiently informative. It avoids redundancy but fails to provide necessary context, making brevity a drawback rather than a strength for tool selection.

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?

Given the tool's complexity (a read operation with one parameter), lack of annotations, 0% schema coverage, and no output schema, the description is severely incomplete. It does not cover purpose differentiation, usage, behavior, parameters, or return values, failing to support effective agent 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 0%, so the description must compensate but adds no parameter information. It does not explain what 'vessel_id' represents (e.g., a UUID identifier for vessels), its format, or where to obtain it, leaving the single required parameter undocumented beyond the schema's basic type and title.

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 'Get vessel details' restates the tool name with minimal elaboration, making it tautological. While it indicates a read operation on vessel resources, it lacks specificity about what details are retrieved or how this differs from sibling tools like 'get_vessels' (which likely lists vessels) or 'get_vessel_valuation' (which focuses on valuation).

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 provided on when to use this tool versus alternatives. It does not mention prerequisites (e.g., needing a vessel_id), contrast with sibling tools (e.g., 'get_vessels' for listing or 'get_vessel_fixture_details' for specific aspects), or specify contexts where it is appropriate, leaving the agent without usage direction.

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