crop_image

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

Annotations already provide idempotentHint=true and destructiveHint=false. The description adds the return format and confirms cropping is non-destructive. No additional behavioral details (e.g., overwrite behavior, error handling) are given beyond what annotations imply.

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 concise sentences front-loaded with the action. Every sentence adds value—definition, parameter summary, return format—with no redundancy or fluff.

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 description, combined with schema and annotations, provides sufficient information for a basic crop operation. Missing details like error cases, format limitations, or coordinate validation, but it is largely complete for a simple tool.

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?

Schema coverage is 100% with each parameter described. The description merely summarizes the parameters (source path, crop box, output path) without adding new semantics or constraints. 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 'Crop an existing image file to a rectangular sub-region,' specifying both the action (crop) and the resource (image file). There are no sibling tools with similar functionality, so it is well-distinguished.

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 context of sibling tools being all about window/process management makes the usage context clear. However, no explicit when-to-use or when-not-to-use guidance is provided, nor are there prerequisites mentioned.

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