list_rules

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

Annotations already declare readOnlyHint: true. The description adds that it is a 'read-only manifest view', takes no arguments, and returns a 'count' plus 'rules' array. This offers concrete behavioral detail beyond the annotation without contradicting it.

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: the first states purpose and result structure; the second gives usage and return format. No redundant wording, front-loaded with the core action.

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 zero-argument list tool with no output schema, the description fully covers purpose, usage, and return shape. It even notes the next step (fetch a body), making it contextually complete relative to its simplicity.

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 input schema has zero parameters, and the description explicitly states 'takes no arguments'. Since schema coverage is 100% trivially, the description adds confirmation of the empty parameter list. Baseline for zero params 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 uses a specific verb 'Enumerate' and identifies a distinct resource: 'behavioral rule the server exposes as a resource'. It explicitly lists what each rule includes (URI, name, description), distinguishing it from sibling tools like list_commands and list_skills.

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?

It provides clear usage context: 'Use to discover which rules are in effect' and explicitly names alternative tools for a follow-up action (read_resource_body or resources/read). This tells the agent when to use this tool and what to do next.

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