region_list_with_ddos_protection

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

With no annotations provided, the description must carry the full burden of behavioral disclosure. It only states the purpose and that it returns a list; it does not mention that this is a read-only operation, whether it requires any authentication, or any potential limitations (e.g., rate limits, pagination). The description repeats the purpose in the 'Returns' section without adding new behavioral context, so it offers minimal transparency beyond the obvious.

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 short but contains redundancy: the first sentence 'List all regions that support DDoS protection' is essentially repeated in the 'Returns' section 'List of regions with DDoS protection capability'. This wastes space and adds no new information. A single sentence would be more concise. The structure is simple and front-loaded, but the redundancy lowers the score.

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 simple zero-parameter list tool with an output schema (indicated), the description is mostly sufficient. However, it does not clarify how this tool relates to region_list or other region tools, nor does it mention that it is a filtered subset. Given the sibling context, a brief note such as 'This is a filtered version of region_list that only includes regions with DDoS protection' would improve completeness. The description covers the core purpose but lacks comparative context.

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 has zero parameters, so the description does not need to explain any. The baseline for 0 parameters is 4, and the description does not add or detract from this. It correctly leaves parameter details to the empty schema, so this score 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 specific resource ('all regions that support DDoS protection') and the action (list). It distinguishes this tool from sibling tools like region_list (which lists all regions) and region_list_by_continent by adding the DDoS protection filter. The verb 'list' and resource are unambiguous.

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 that this tool should be used when the user needs regions with DDoS protection capability, but it does not explicitly state when to use this over alternatives like region_list or region_list_by_continent. There is no mention of scenarios where this tool is not appropriate. The usage is implied from the name and description, but not made explicit.

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