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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely useful non-annotation context — the 10-credit Tier 1 cost and the Agrippa group — but says nothing about what the reading contains or how it is produced.

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?

Three short lines, front-loaded, with no filler. The group and cost tags earn their place as billing/routing context; the only weakness is that the brevity comes at the cost of substance rather than being tight specification.

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?

With an output schema present, return values need not be explained, but the description still fails to say that this is a geomancy figure lookup, how it differs from the fifteen sibling geomancy figures, or what a caller gets back. For a 17-figure family with near-identical definitions, that gap is material.

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%, so both optional parameters (fields, precision) are fully documented in the schema with examples and defaults. The description adds nothing about them, which is the expected baseline when the schema does the heavy lifting.

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 'Greater Fortune: lasting success' restates the figure's name and gives its traditional meaning, but never states what the tool does — no verb such as 'return the geomancy reading for the Fortuna Major figure'. An agent must infer the operation entirely from the name and sibling pattern.

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 when-to-use guidance, no condition for choosing this figure over the sibling figures (e.g. fortuna_minor, laetitia, tristitia), and no mention of inputs or prerequisites. The [Group] and [Cost] lines describe metadata, not usage.

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