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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and a closed world, so the safety profile is covered. The description adds genuinely useful non-schema context – the group, the POST endpoint, and the cost (10 credits, Tier 1) – but says nothing about what the reading contains or any constraints on invocation.

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 text is short and front-loaded, but the brevity stems from under-specification rather than disciplined concision: the theme phrase carries no operational information, and the bracketed metadata is the only concrete content. It is neither wasteful nor adequately informative.

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, annotations covering safety, zero required parameters, and full schema coverage, much of the burden is carried elsewhere, so the definition is not grossly incomplete. However, for a tool embedded among 16 near-identical geomancy siblings, the absence of any statement about what a reading returns or when this figure applies leaves a real selection 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 description coverage is 100%, so both optional parameters (`fields`, `precision`) are fully documented in the schema itself; the description adds nothing about them. Per the baseline rule, a 3 is appropriate 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 gives only the divinatory keywords "Beauty, harmony, love" – the symbolic meaning of the Puella figure – with no verb or statement of what calling the tool actually does (e.g. returns a geomancy reading for this figure). It does not distinguish the tool from the 15 sibling geomancy figure tools beyond the figure name already present in the tool name. This is keyword association rather than a purpose statement.

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 indication of what input/question triggers this figure versus Puer, Albus, or any other geomancy sibling, and no prerequisites. The agent is left to infer everything from the one-word theme.

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