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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description only needs to add check semantics — and it does, enumerating the clash categories (bw film + colour grade, stacked grades, day/night palette mismatch, anamorphic in vertical frame, interior light + outdoor subject) and stating 'ok: true means clean'. It does not describe the failure payload or whether a failed lint blocks briefing, but with annotations and an output schema carrying much of the load this 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?

Purpose and scope are front-loaded, followed by the worked call example and the 'ok: true' contract. The middle clash enumeration is a dense run-on that would scan faster as a list, but every clause carries real information about what gets validated.

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?

For a read-only linter with a full output schema, the description supplies enough: what it validates, an example invocation, and the success signal. It stops short of describing the failure report, which the output schema presumably covers, so nothing critical is missing for invoking it correctly.

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 baseline is 3, but the description adds semantics the terse schema blurbs do not: it ties aspect to a concrete check ('an anamorphic lens in a vertical frame') and subject to another ('an interior light with an outdoor subject'), showing how those optional params activate additional checks. The worked example also clarifies the hand_ids array shape.

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 ('Check card ids you combined yourself for clashes before briefing') and immediately distinguishes itself from siblings by scoping to hand-authored combinations rather than deals or briefs. An agent can tell it apart from deal_hand and brief without opening either schema.

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?

Gives both the positive condition ('card ids you combined yourself ... before briefing') and an explicit exclusion ('deal_hand and brief already lint their own output'). The alternative tools that would otherwise look relevant are named and ruled out, leaving nothing to inference.

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