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

Annotations already establish this as a read-only, idempotent, non-destructive, closed-world call, so the safety profile is covered. The description adds real substance beyond them: it discloses the rule categories, that verdict/risk-score derivation is included, and — notably — 'what the rules cannot catch', which is a genuine limitation disclosure.

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?

Front-loaded with the verb and scope, then the returned content, then the usage cue, then the no-argument note. Dense and mostly waste-free, though 'It takes no text' partially restates the empty schema.

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?

An output schema exists, so return values need not be described, yet the description still outlines the rule fields and the verdict/risk-score explanation. For a no-parameter read-only listing tool this is fully sufficient.

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, which is the baseline-4 case. The description reinforces this with 'It takes no text', usefully disambiguating it from scan_text, which presumably does take text.

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 (list) and resource (injection rules) and pins the scope to the rules that 'scan_text uses', naming the sibling explicitly. It also enumerates the returned dimensions (category, severity, detection target), so an agent can distinguish it from scan_text without opening the schema.

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?

Gives a clear usage context: 'Use it to explain a finding', which ties it to the output of scan_text. It does not spell out when-not to use it or name an alternative for other needs, so it stops short of full when/when-not guidance.

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