Marlo MCP

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

With no annotations provided, the description carries the full burden of behavioral disclosure but offers minimal information. 'list all vendors' implies a read-only operation but doesn't specify whether this requires authentication, what permissions are needed, whether results are paginated (though parameters suggest they are), or what format the output takes. The description doesn't mention rate limits, error conditions, or any side effects.

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 at just three words, which could be appropriate if it were more informative. There's no wasted verbiage, but it's arguably under-specified rather than efficiently concise. The structure is simple but doesn't follow best practices of front-loading the most important information.

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?

For a tool with 3 parameters, no annotations, and no output schema, the description is inadequate. It doesn't explain what a 'vendor' represents in this system, what fields are returned, how results are ordered, or any limitations on the listing. The context signals show this is a non-trivial tool (3 parameters, pagination, search capability) that deserves more complete documentation than a three-word tautology.

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 description provides no parameter information whatsoever, while the schema has 3 parameters with 0% description coverage. However, the parameter names (page, per_page, search) are reasonably self-explanatory for a listing operation, suggesting pagination and search functionality. The description doesn't add value beyond what can be inferred from parameter names, but the baseline is 3 since the schema provides the structure even without descriptions.

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 'list all vendors' is a tautology that essentially restates the tool name without adding meaningful specificity. It doesn't distinguish this tool from other list_all_* tools in the sibling set, nor does it specify what constitutes a 'vendor' in this context. While the verb 'list' is clear, the resource 'vendors' lacks context about what domain or system these vendors belong to.

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 sibling tools like 'get_vendor_details' and 'list_all_customers' available, there's no indication of when this list operation is appropriate versus retrieving individual details or listing other entity types. No prerequisites, exclusions, or comparison to similar tools are mentioned.

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