yazio-mcp

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the agent knows this is a safe, repeatable read operation. The description adds no behavioral context beyond what annotations provide - no information about authentication needs, rate limits, or what specific data is returned. With annotations covering the safety profile, a baseline 3 is appropriate.

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, efficient sentence that states exactly what the tool does without any wasted words. It's appropriately sized for a simple retrieval tool and front-loads the essential 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 simple read-only tool with good annotations (readOnlyHint, idempotentHint) and no parameters, the description is minimally adequate. However, without an output schema, the description doesn't explain what data is returned (e.g., format, structure, or specific dietary fields). Given the complexity is low but output is undocumented, a score of 3 reflects this gap.

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 zero parameters with 100% schema description coverage, so the schema fully documents the absence of inputs. The description doesn't need to compensate for any parameter gaps. A baseline of 4 is appropriate for parameterless tools where the schema already provides complete documentation.

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 clearly states the verb 'Get' and the resource 'user dietary preferences and restrictions', making the purpose immediately understandable. It doesn't explicitly differentiate from sibling tools like 'get_user' or 'get_user_settings', but the specificity of 'dietary preferences and restrictions' provides reasonable distinction.

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 like 'get_user' (which might include dietary data) or 'get_user_settings'. There's no mention of prerequisites, context, or exclusions that would help an agent choose between similar retrieval tools.

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