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

No annotations provided, so description must carry behavioral context. It only states the action and return fields, without disclosing idempotency, error handling, validation of birth_date, or any side effects. This is insufficient for a tool with no annotations.

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?

Two concise sentences, front-loaded with core action, and no redundant information. Efficiently uses words to convey purpose and return, plus a useful cross-reference.

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 tool with one parameter, the description covers action, return structure (though no output schema provided), and a pointer to related tools. It is nearly complete but could briefly mention validation or edge cases (e.g., valid date range).

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?

Schema description coverage is 100%, with the schema already specifying 'Birth date in YYYY-MM-DD format'. The description adds no additional meaning or constraints beyond echoing the format. Baseline 3 is appropriate.

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?

Description clearly states 'Calculate numerology life path number from birth date' with a specific verb and resource. It also distinguishes this from hundreds of sibling calculators by mentioning 'life path numerology' and directing to list_bundles for related fun calculators, which helps in differentiation.

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?

No explicit guidance on when to use vs. alternatives. The cross-reference to list_bundles implies related fun calculators but does not clearly state exclusions or prerequisites. The purpose is clear, but usage context is lacking.

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