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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false, and destructiveHint=false, covering safety and determinism. The description adds the 'seeded' nature (explaining idempotency) and a cost of 10 credits, which are useful behavioral details beyond the annotations.

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 very short and front-loads the method name, with no wasted prose. However, for a tool with three parameters and an output schema, it is arguably under-specified rather than appropriately sized, falling short of what a concise-yet-informative description should include.

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?

Given the tool's complexity (3 parameters, output schema present, multiple I Ching siblings), the description is incomplete. It does not explain what the tool returns (though the output schema covers that) and, more importantly, provides no guidance on selecting it over other I Ching tools or on how the seed affects results.

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 67%: the fields and precision parameters are well documented in the schema, but the seed parameter has no schema description. The word 'Seeded' in the description hints that seed controls randomness, but it does not explain the anyOf number/string format or compensate for the missing schema description.

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 'Seeded 3-coin method' restates the tool name/action with a qualifier and does not state what the tool actually produces (e.g., an I Ching hexagram or reading). It fails to distinguish this tool from sibling I Ching tools like astroway_iching or astroway_iching_with_changing_lines.

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 guidance on when to use this tool versus alternatives, no exclusions, and no prerequisites. The only context is a group tag and a cost tag, neither of which tells an agent when this specific coin-throwing method is appropriate.

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