Marlo MCP

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool 'get details,' implying a read-only operation, but does not specify aspects like authentication requirements, rate limits, error handling, or the format of returned details. This leaves significant gaps in understanding the tool's behavior.

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 a single, straightforward sentence that efficiently conveys the core action. It is front-loaded with the main purpose and avoids unnecessary words, though it could be slightly more informative without losing 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?

Given the lack of annotations and output schema, the description is incomplete for a tool that retrieves details. It does not cover what details are returned, how they are structured, or any behavioral traits like pagination or error cases. This makes it insufficient for an AI agent to fully understand the tool's context and usage.

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?

The input schema has 1 parameter with 0% description coverage, but the description adds no semantic information beyond implying a 'vessel_fixture_id' is needed. It does not explain what a vessel fixture is, the format of the ID beyond the schema's 'uuid' hint, or any constraints. With low schema coverage, the description fails to compensate adequately, resulting in a baseline score.

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 states the tool's purpose as 'get details of a specific vessel fixture,' which includes a verb ('get') and resource ('vessel fixture'), making it clear what the tool does. However, it does not differentiate from sibling tools like 'get_vessel_details' or 'get_voyage_details,' leaving ambiguity about the specific scope of 'vessel fixture' versus other related entities.

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 provides no guidance on when to use this tool versus alternatives. It does not mention prerequisites, context for selecting it over similar tools (e.g., 'get_vessel_details' or 'list_all_vessel_fixtures'), or any exclusions, relying solely on the tool name for inference.

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