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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description does add two genuinely useful behavioral facts not in the annotations: the group ([Geomancy (Agrippa)]) and the cost (10 credits, Tier 1). It still says nothing about what the call returns or what triggers it, but with annotations carrying the safety burden a 3 is fair.

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 description is minimal and front-loaded, and the bracketed metadata tags are cleanly structured. However, the three-word body is under-specified rather than genuinely concise — the brevity comes at the cost of the tool's core explanation.

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 for a tool with no required parameters whose purpose is entirely unstated, the description leaves the agent unable to know what invoking it actually produces or when it should be chosen over the 15 sibling geomancy tools.

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% and both parameters (fields, precision) are fully documented in the schema itself. The description adds no parameter guidance whatsoever, which is acceptable given the schema does the work, but earns no credit above baseline.

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 is "Sadness, depression, melancholy." — a list of the figure's symbolic meanings rather than a statement of what the tool does. It effectively restates the title ("Tristitia: Sorrow") and never uses a verb or names a resource, so an agent cannot tell whether it returns an interpretation, a chart placement, or a description of the geomantic figure.

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 prerequisites, and no mention of the 15 sibling geomancy figure tools it competes with. The only routing signal is the implicit keyword match on the figure's meaning, which the agent must infer on its own.

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