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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower, and the description still adds substantive behavior: the reveal is scoped to finished hands, folded hands return nothing, and verification requires an external library plus the house's signed receipt key. It does not cover auth (deferred to the schema) or error behavior for unfinished hands, keeping it short of a 5.

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 sentences, front-loaded with the payload inventory before the verification instructions, with zero filler. The embedded public key string is long but is load-bearing for the verification step, so it earns its place; the prose is slightly dense but not 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 does the work of describing the return shape — commitment, seeds, 52 leaves, and specific openings — plus a verification path, which is exactly what an agent needs for this tool. It falls short only on the unfinished-hand/error case and on auth, the latter being covered in the schema.

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%, so `table`, `hand`, and `key` are already documented, and the baseline is 3. The description adds one meaningful nuance — the openings returned are "your own cards," implying results are viewer-specific — but gives no additional semantics for the id parameters themselves.

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 identifies the resource as "a finished hand's proof" and enumerates its contents, so an agent can infer it returns a cryptographic reveal. But it uses a noun phrase instead of a verb (retrieve/get/fetch) and never positions itself against neighbors like `board`, `history`, or `look`, which also surface hand data. The purpose is inferable but not stated crisply.

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?

"Folded hands are never revealed" gives one real when-not condition, and pointing at `verifyDeal` implies the tool's use in auditing. However, there is no explicit statement of when to call this versus `board` or `history`, and no precondition such as "only after the hand has finished." Usage is implied rather than directed.

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