scan_waf_coverage

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

No annotations are provided, so the description carries full burden. It explicitly states 'Read-only. Does not modify any AWS resources,' which is a key behavioral trait. However, it does not disclose other potential behaviors such as rate limits, authentication requirements, or what happens during the scan (e.g., temporary locks). The description is adequate but could be more thorough.

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?

The description is extremely concise with two sentences, no wasted words. It front-loads the purpose and immediately adds the read-only attribute. Every sentence contributes essential information.

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?

Given the tool's simplicity (1 optional parameter, no output schema, no annotations), the description covers the core purpose and safety. However, it could briefly mention the type of output or any prerequisites (e.g., required permissions) to be 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 input schema has 100% description coverage for the single parameter 'region', which already explains it defaults to the server region. The tool description does not add any additional meaning beyond the schema, so the baseline of 3 is appropriate.

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's specific purpose: running a WAF Coverage security scanner. It uses a specific verb ('Run') and resource ('WAF Coverage security scanner'), and distinguishes itself from sibling tools by emphasizing that it is 'only' for this purpose and is read-only.

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 description implies when to use the tool (when a WAF Coverage scan is needed) but does not provide explicit guidance on when not to use it or suggest alternatives. The word 'only' gives some context, but without exclusion criteria or reference to sibling tools, the guidance is minimal.

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