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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false; the description adds that the data is 'live' and includes defaults, implying dynamic availability over static metadata. This enriches behavioral context without contradicting the annotations.

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 efficiently structured sentences front-load the purpose, enumerate the facet types, and conclude with a concrete usage tip. No redundant or filler content exists.

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-argument read-only tool with an output schema and safety annotations, the description provides everything an agent needs: what the tool returns, why it is useful (learn valid filters), and that defaults are included. Nothing is missing for correct invocation.

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?

The tool takes zero parameters, so no parameter details are needed. The schema coverage is trivially 100% with an empty object, and the baseline of 4 applies when there are no parameters to explain.

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 states the tool returns filterable metadata for search_rules, enumerating specific facet types (jurisdictions, domains, roles, block types, statuses, tax years, topics) and defaults. This verb+resource specificity distinguishes it from sibling list tools by tying it directly to the search_rules workflow.

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?

Explicitly instructs to call this before search_rules to learn valid filter values, preventing guessing. It gives a clear when-to-use directive but does not name alternative tools or describe when not to use it, so it falls short of the full 5.

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