Marlo MCP

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

No annotations are provided, so the description must fully disclose behavioral traits. 'Get all voyages' only implies a read operation without details on permissions, rate limits, pagination, or response format. It lacks critical information such as whether this is a safe, read-only call or if it has side effects, making it inadequate for transparency.

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 'Get all voyages' is extremely concise, consisting of three words. While it avoids unnecessary verbosity, it is under-specified rather than efficiently informative. Every word earns its place, but the brevity comes at the cost of clarity, making it more of a placeholder than a helpful description.

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 list operation with no parameters) and the absence of annotations and output schema, the description is incomplete. It fails to explain what 'all voyages' includes (e.g., scope, format, or limitations) or the behavioral context, leaving significant gaps for the agent to infer usage and results.

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 tool has 0 parameters with 100% schema description coverage, meaning the schema fully documents the absence of inputs. The description does not add parameter semantics, but since no parameters exist, this is acceptable. A baseline of 4 is appropriate as the description need not compensate for any gaps, though it doesn't enhance understanding beyond the schema.

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 all voyages' is a tautology that merely restates the tool name without adding meaningful context. It specifies the verb 'Get' and resource 'voyages', but lacks specificity about what 'all voyages' entails (e.g., scope, format, or filtering). Compared to siblings like 'get_voyage_details' or 'get_voyage_profit_and_loss', it fails to distinguish its purpose clearly, making it vague in practice.

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. With siblings such as 'get_voyage_details' (for specific voyages) and 'get_voyage_profit_and_loss' (for financial data), there is no indication of context, exclusions, or prerequisites. This absence of usage instructions leaves the agent without direction in selecting among related tools.

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