Cauda Draconis

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 fully covered. The description adds one genuinely useful behavioral fact not in the annotations: the cost of 10 credits (Tier 1), which matters for call budgeting. It says nothing about permissions, caching, or return shape, so it clears the lower bar set by the annotations but does not exceed it.

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?

Two short, front-loaded fragments with no filler; the figure name and its core meaning come first. The bracket metadata is arguably boilerplate, but it is compact and carries cost/endpoint information. Slight deduction because the terse keyword style shortchanges an agent looking for actionable scope.

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 zero params, an output schema, and full annotations, the structured data carries most of the load, so this is near-adequate. Still missing is what the response contains (figure description, correspondences, interpretation length) and the only-to-use-this-figure condition. For a 10-credit paid call, that omission leaves an agent guessing at value.

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, so per the rubric the baseline is 4. There is nothing for the description to disambiguate on the input side; the empty schema is self-explanatory.

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?

Names the resource (Cauda Draconis / Dragon's Tail) and gives keyword associations 'endings, exit', but supplies no verb saying what the tool does with it. An agent must infer that this is a per-figure lookup/meaning endpoint rather than, say, a generator or a chart calculation, and nothing distinguishes it functionally from the 15 sibling geomancy figure tools beyond the figure 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 guidance on when to call this versus astroway_geomancy_caput_draconis or the other geomancy figures, nor on context (e.g. when a reading yields this figure). The only usage-adjacent content is the endpoint and credit-tier metadata, which is administrative rather than directional.

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