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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. Beyond that, the description discloses the return shape (id, category, label, description, prebuilt FieldRule[] payload) and that the payload is ready to use directly, which is meaningful since no output schema exists; it omits nothing an agent needs for a parameterless static listing.

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 resource and its purpose, then the entry structure. The illustrative list of preset categories earns its place by telling the agent what kinds of presets exist; nothing is redundant.

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 parameterless, read-only catalog with no output schema, the description supplies everything needed: what it returns, the fields per entry, and how the FieldRule[] payload is consumed downstream. There is no missing prerequisite, pagination, or side-effect information to add.

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 there is no parameter semantics to explain; baseline 4 applies. The description correctly adds no parameter discussion and instead spends its words on the return payload.

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 ('Returns the cookbook of one-click rule presets') and enumerates what the presets cover, so an agent knows this is a static catalog of reusable rule bundles. It also implicitly distinguishes itself from update_field_rules by naming that sibling as the consumer of this output.

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 phrase 'one-click rule presets' and 'splat directly into update_field_rules' tells the agent the intended workflow: fetch presets here, then apply them via update_field_rules. It does not explicitly state when NOT to use it (e.g., authoring custom rules from scratch), but the context is clear enough for a zero-parameter read tool.

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