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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description does add genuinely useful non-schema context — the 10-credit (Tier 1) cost and Agrippa system grouping — but says nothing about the response shape or any behavioral edge cases beyond that.

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?

Extremely tight — one evocative clause plus bracketed metadata tags, with no filler. Nothing is wasted, though the brevity is partly under-specification rather than pure economy.

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?

An output schema exists so return values need not be explained, and annotations cover safety, but the core purpose — what the tool returns and how it differs from its many geomancy siblings — is absent. For a figure-lookup tool in a crowded sibling set, the description is not complete enough to select it confidently.

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%: both optional parameters (fields, precision) are fully documented in the schema with examples and defaults. The description contributes nothing about parameters, which is the expected baseline 3 when the schema does all the work.

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 evocative keywords for the Rubeus figure ('Passion, anger, blood: ill omen') but never states what the tool actually does — no verb, no 'returns the meaning of the Rubeus geomantic figure'. With 15 sibling geomancy figure tools distinguished only by name, an agent gets thematic flavor but no functional statement of purpose.

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 mention of how it relates to the other fifteen geomancy figure tools (e.g. whether it returns just this figure's interpretation), and no prerequisites or alternatives. The Group and Cost tags are metadata, not usage direction.

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