list_images

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

No annotations are provided, so the description must carry the transparency burden. It discloses the sorting behavior ('newest first') but does not mention other behavioral aspects such as return format, read-only nature, behavior when the directory is empty, or any error conditions. For a simple list tool, this is adequate but not comprehensive.

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 sentence that is front-loaded with the action and scope. It contains no filler or redundant information. Every word contributes to the meaning.

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?

The tool is a simple listing operation with one optional parameter and no output schema. The description covers the core behavior but does not specify what fields are returned for each image (e.g., file name, path, timestamp) or how the results are formatted. Given that an output schema is absent, the description falls short of fully documenting the tool's response.

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 provides a complete description for the sole parameter 'limit' (100% coverage). The tool description adds no additional meaning or context beyond what the schema already specifies, so the baseline score 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 function: 'List all screenshot images in the screenshots directory, sorted by newest first.' It uses a specific verb ('list'), identifies the resource ('screenshot images'), and adds a scope detail ('screenshots directory'). This differentiates it from siblings like view_image or delete_image.

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 provides no explicit guidance on when to use this tool versus alternatives. It does not mention any exclusions, prerequisites, or refer to sibling tools like view_image or delete_image. The intended use case is implied but not stated.

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