Expression / Destiny (pythagorean)

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

Annotations already declare read-only, idempotent, non-destructive, closed-world behavior, so the description adds useful context beyond them: the endpoint, required inputs, and a 10-credit cost. It does not describe return values, but an output schema exists, lowering the burden.

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 compact and front-loaded: the calculation appears first, followed by structured metadata for group, endpoint, required parameters, and cost. Every line carries useful information with no filler.

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 two-parameter calculation with an output schema and rich annotations, the definition covers cost, required inputs, and methodology. The unexplained role of the required 'date' parameter is the main remaining gap, but the tool is otherwise invocable as defined.

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 coverage is 0%, so the description must compensate. It clarifies that 'name' should be the full birth name (all letters) but merely lists 'date' as required without explaining its role in an Expression calculation, leaving a meaningful gap.

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?

States a specific verb and resource: calculating the Expression (Destiny) number using Pythagorean numerology. The parenthetical '(all letters, reduced)' subtly distinguishes it from sibling tools like soul_urge (vowels) and personality (consonants), though it does not explicitly name those alternatives.

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?

Usage is implied by the clear name and the 'all letters' note, but there is no explicit guidance on when to choose this over the many other Pythagorean numerology siblings (life_path, soul_urge, personality, etc.). No exclusions or prerequisites are stated.

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