Edit image

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

Annotations already disclose the tool is not read-only, not idempotent, and not destructive. The description adds minimal behavioral context: that it operates via an 'OpenAI-compatible Images API' and supports 1–16 input images. It doesn't mention side effects like API costs, or clarify state changes, but with annotations present, the bar is lower. A score of 3 is appropriate because it adds some context but not rich behavioral 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, tightly written sentence that front-loads the core action and scope. Every word adds value, and there is no fluff or repetition of schema details. It is an excellent example of concise, well-structured documentation for a tool with complex parameters.

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 tool has 11 parameters and an output schema, the description is appropriately high-level. It mentions the input images count, the operation types, and the configured API, which covers the prerequisites (setup_image_api). The output schema handles return values. No critical context like licensing or requirements seems missing, so a 4 is merited.

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 description coverage is 64%, so the schema carries most parameter semantics. The description does not explicitly describe any parameters, but it does reinforce the meaning of 'prompt' and 'images' by stating 'Edit, combine, or mask one to sixteen input images', which aligns with the images parameter. It adds no new information about other parameters like size, quality, or delivery, so the baseline 3 is warranted.

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 starts with a specific verb ('Edit, combine, or mask') and clearly identifies the resource ('one to sixteen input images') and the backend ('configured OpenAI-compatible Images API'). This distinguishes it from the sibling tools, especially generate_image, by focusing on modifying existing images rather than creating new ones.

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 clearly implies use cases: editing, combining, or masking input images. It doesn't explicitly name alternatives or state 'when not to use', but the phrasing makes it evident that this is for working with existing images, not generating from scratch. Since guidelines are implied rather than directly contrasted with siblings, it earns a 4, not a 5.

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