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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds genuine behavioral value beyond that by disclosing the result cap (24) and the fact that the list is not paginated, which directly affects how an agent should consume results.

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?

Three short sentences, front-loaded with the purpose, then the origin of the screenshots, then the result-size constraint. No wasted wording, though the middle sentence about how screenshots were captured is more flavor than operational detail.

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 single-parameter list tool with no output schema, the description covers purpose, result cap, and pagination behavior. It could say a bit more about what each screenshot entry contains, but it is adequate for correct invocation.

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 a single required parameter (id) with 100% schema description coverage ('Site identifier.'), so the schema fully carries parameter meaning. The description adds nothing about the id beyond what the schema states, making the baseline 3 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 states a specific verb (List) and resource (a site's FeelingSurfViewer screenshots) and clarifies that these are screenshots captured while the app surfed the site. It implicitly distinguishes itself from the singular get_screenshot sibling via 'List', but never names that sibling explicitly, so differentiation is left to inference.

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 gives useful scoping context (most recent, up to 24, not paginated) but offers no explicit when-to-use guidance or comparison to alternatives like get_screenshot or list_surf_sessions. Usage is implied rather than stated.

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