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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description usefully adds cost (10 credits, Tier 1) and the endpoint, but says nothing about auth requirements, rate limits, or what the calculated output contains beyond what the output schema provides.

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 core explanation is a single front-loaded sentence, with grouped metadata in compact brackets. Every element earns its place, though the bracket block is slightly noisy relative to the short prose.

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 single-value compute tool with an output schema, the description covers what is calculated and from what input, so return values need no explanation. It is nonetheless thin on routing among the ~70 numerology siblings, which is the main contextual 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?

Schema coverage is 50%: `fields` and `precision` are documented in the schema, but `date` is not, and the description does not explain the date's role. It does add real semantic value for `name` by specifying it must be the full birth name whose consonants drive the calculation — meaning not present in the schema.

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 names a specific verb and resource — 'Calculate the Personality number' — and narrows it to the Chaldean system and to the consonants of the full birth name. That is enough to separate it from the many pythagorean/kabbalistic/vedic personality siblings, though it never explicitly contrasts them.

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?

There is no statement of when to choose this over astroway_numerology_kabbalistic_personality or pythagorean_personality, or when a Personality number is the right reading versus Soul Urge/Expression. The only guidance is the bracketed 'Required: name, date', which is input plumbing rather than usage.

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