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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive behavior. The description adds the auth requirement ('Needs a key') and clarifies the response includes hit counts, which goes beyond the annotations without contradicting them.

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 short sentences earn their place: the first front-loads the resource and return contents, and the second provides the auth/docs link. There is no filler or repetition.

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 no-parameter listing tool, the description is sufficient: it states what is returned, whose rules are returned, and the key requirement via docs. The term 'mite' is assumed domain knowledge emerging from the community definition, and there is no output schema, so a couple of details are left implicit.

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?

This tool has zero parameters and the schema is fully covered at 100%, leaving no parameter semantics for the description to add. With 0 params, the baseline is 4.

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 clearly names the resource ('standing rules this mite has set') and the included data ('with how often each has hit'). It does not explicitly contrast with sibling rule tools like create_rule or delete_rule, so it stops just short of full differentiation.

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 implies this is the read/listing tool for standing rules, but it never states when to use it versus create_rule, delete_rule, or test_rule. The 'Needs a key' line adds a useful precondition, but the when-to-use context remains only implied.

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