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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is covered. The description adds real value beyond them: the default-form behavior when the key is omitted, and the differing depth of the short versus full response. It omits error handling for unknown domain/card names, but that is a minor gap.

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 core purpose is front-loaded in the first clause, followed by the form behavior. It is somewhat dense and the enumerated content lists overlap with the schema description, but every sentence carries information and nothing is padded.

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 no output schema, the description carries the burden of explaining return content and does so for both form variants, which is the key unknown for an agent. All three parameters are documented. It stops short of describing failure modes or how the pair names must match list_cards output beyond the schema note.

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 coverage is 100%, so the baseline is 3, but the description goes further by spelling out what the 'short' form returns (a page sufficient to write a first request) and what 'full' adds (each bound's reason, the validation record, each stop's meaning). This meaningfully extends the enum's semantics beyond the schema text.

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?

States a specific verb and resource ('Describes one domain and card pair') and enumerates the exact content returned (inputs, units, bounds, step limits, reject names, advisory flags, frame slots, worked examples). This clearly distinguishes it from the sibling list_cards, which only names cards rather than describing a single pair in depth.

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?

The description explains the short-vs-full tradeoff and that omitting form yields the full answer, which is genuine usage context. However, it never states when to reach for describe_card versus siblings like list_cards or describe_solver, and gives no exclusions or prerequisites. Usage is implied rather than guided.

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