check_rule

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

With no annotations, the description carries the full burden. It does disclose the return payload ('violations with reasons and alternatives'), which is the most useful behavioral fact, but it never states that the call is non-mutating, requires no auth, or what an empty result looks like. 'Check' implies a read, but that is inference rather than disclosure.

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, zero filler, and the action is front-loaded ahead of the return-value note. Every clause earns its place.

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 one-parameter, read-only checker with no output schema, the description is nearly complete: it covers what is checked and what comes back. It could be fuller by noting the clean-result case or its relationship to check_html, but nothing critical is missing.

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% and the single parameter is fully documented in the schema with a concrete example. The description adds no extra meaning about the classes string (e.g. format constraints or whether multiple strings are accepted), so the baseline of 3 applies.

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 gives a specific verb (check) and resource (class strings against this design system's prohibition rules), which is enough to separate it from get_rules or get_token. It does not explicitly differentiate itself from the sibling check_html, so an agent must infer that one takes class strings and the other markup.

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 statement of when to use this versus check_html, get_rules, or get_token, and no prerequisites such as running it before shipping markup. Usage is only implied by the phrase 'this design system's prohibition rules'.

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