resize_image

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

The description discloses that the tool saves the resized image to disk, which is an important side effect. However, it does not mention whether it overwrites existing files, what happens if the output directory doesn't exist, supported image formats, or error behavior. With no annotations, these gaps leave behavioral transparency partially incomplete.

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 two sentences and about 35 words, front-loaded with the core purpose. Every sentence contributes essential information without redundancy.

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 covers the main workflow (path, mode, options, output) but lacks any mention of return values, error handling, or limitations like supported file types or overwrite behavior. Since there is no output schema and no annotations, the description should carry more of this burden to be fully complete.

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 description adds meaning beyond the schema by explaining that the 'image path' maps to file_path, 'resize mode' to image_resize_type, and 'percentage or width/height' to resize_percentage or width/height. It also clarifies that output directory and file name are optional, which is especially helpful since the schema does not describe those two parameters. This compensates for the 75% schema coverage.

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 says 'Resize a local image' with a specific verb and resource, and distinguishes from sibling tools like compress_image or crop_image. It also mentions the API and the two modes (Percentage or Specific), making the purpose 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 gives clear usage context: provide image path, resize mode, and options. It explains the two modes and optional output settings, but it does not explicitly mention when to use this tool versus alternatives (e.g., compress vs resize) or when not to use it.

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