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

With no annotations, the description must fully disclose behavior. It states the tool calculates due date and gestational week from last period, but does not discuss assumptions (e.g., 28-day cycle), error handling for invalid dates, or any safety aspects. This is adequate but minimal.

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 two sentences with no filler, front-loading the core purpose. Every sentence adds value, making it highly efficient.

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 simplicity (one parameter, no annotations, output schema exists but is not detailed), the description covers the basics: input, output, and a pointer to related tools. It is largely complete for an agent to invoke correctly, though it could benefit from usage guidance.

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 already provides a clear description for the only parameter ('Last menstrual period date YYYY-MM-DD') with 100% coverage. The description adds no additional parameter-specific meaning beyond what the schema provides.

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 'calculate due date and current gestational week from last period', specifying the verb, resource, and input. However, it does not differentiate from the sibling tool 'calculate_due_date', which could cause confusion.

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 mentions 'See list_bundles for related 'sante' calculators' but gives no explicit guidance on when to use this tool versus other due date calculators (e.g., 'calculate_due_date' or 'calculate_cat_pregnancy'). No when-not-to-use or alternative recommendations.

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