List rules

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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds the note that 'Optional rules are marked' and lists returned fields, but the field list largely duplicates the existing output schema, so incremental behavioral value is modest.

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 tightly packed sentences: action and return payload first, then the optional-rule marker. No filler, nothing to trim.

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?

With an output schema and annotations covering safety, return-format detail is correctly left to structured fields, and the description covers scope and filter behavior adequately. Only a pointer to explain_rule for per-rule detail would make it fully complete.

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 single severity parameter has 100% schema description coverage ('Only rules at this level') plus an enum, so the schema carries the meaning. The description adds nothing about the filter, matching the baseline 3 when schema does the heavy lifting.

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?

Clear specific verb+resource: 'List the CES rules this server enforces', with the returned fields enumerated. It is readily distinguishable from check_text/fix_text/measure_text by activity type, though it never explicitly contrasts itself with those siblings.

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?

Usage is only implied — an agent infers this is a discovery tool to run before explain_rule or check_text. There is no explicit when-to-use statement, no preconditions, and no named alternative, so it sits at minimum-viable.

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