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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that the output is 'viewable images' and clarifies it returns 'region screenshots', but it does not disclose other behavioral traits like pagination, size, or how the images are encoded. This adds some context but not substantial detail.

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 a single, concise sentence that is front-loaded with the verb 'Return'. Every word contributes to the meaning, with no repetition or filler. It is perfectly sized for a simple tool.

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 low complexity (1 parameter, no nested objects) and the presence of an output schema (not shown), the description provides sufficient context. It clearly states what the tool does and why it is useful. Annotations cover the safety profile, so no further detail is needed.

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?

There is only one parameter, annotation_id, and the schema description coverage is 0%. The description mentions 'attached to an annotation' but does not explain the format, source, or any constraints on annotation_id. It adds little beyond the parameter name, failing to compensate for the lack of schema documentation.

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 'Return' and clearly identifies the resource: 'region screenshots attached to an annotation'. It states the purpose ('so you can see exactly what the reporter pointed at') and implicitly distinguishes from siblings like get_annotation (which returns annotation details) and list_annotations (which lists annotations).

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 conveys a clear use case: when you need to visually see the screenshots attached to an annotation. This context is clear, though it does not explicitly name alternative tools or state when not to use it. No exclusions are mentioned, so it earns a 4 rather than a 5.

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