Puella: Girl

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

Annotations already cover safety (readOnlyHint, idempotentHint, non-destructive, closed-world), so the description only needs to add operational context. It does contribute two genuinely useful facts not in annotations — a fixed cost of 10 credits (Tier 1) and the POST endpoint — but says nothing about what the response contains or whether the figure is static reference data.

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?

Very short and front-loaded, with metadata lines cleanly separated from the prose. Nothing is padded, though the one content sentence carries almost no operational information, so brevity here reflects thinness as much as discipline.

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?

Zero parameters and an existing output schema lower the bar considerably, and cost plus endpoint are disclosed. What remains missing is the core fact an agent needs: that this is a reference lookup of a single fixed geomantic figure and what it returns, which is why it is only minimally viable for a no-input tool.

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?

The tool takes zero parameters and the schema is an empty object at 100% coverage, so the baseline applies. There is nothing parameter-related the description could usefully add.

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?

"Beauty, harmony, love" states the figure's thematic keywords, not what the tool does. There is no verb or statement of the operation (return the figure's meaning, correspondences, or a generated reading), and nothing distinguishes it from the 15 other astroway_geomancy_* sibling endpoints beyond the name itself.

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 when-to-use, when-not-to-use, or alternative routing is given. An agent gets no signal on how to choose between Puella and Puer, or between a geomancy figure lookup and astroway_ai_interpret_element; the Group tag only implies a family, not a selection rule.

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