edit_image

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

With no annotations, description carries full burden. It discloses that the tool saves the result to a file, returns a path and optional preview. Describes default model and output directory fallback. Missing details about potential side effects or permission requirements, but transparent enough.

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?

Well-structured with bullet points for args. Front-loaded with core purpose and key differentiators. No unnecessary words. Efficient and readable.

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 tool with 5 parameters and no output schema, the description covers inputs, behavior, return format (path + optional image), and default behaviors. Complete for an agent to invoke correctly.

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 0%, so description must compensate fully. It explains each parameter: image_paths (absolute paths), prompt (instruction), model (two named options), output_dir (defaults), return_image (boolean, preview). Adds meaning beyond the schema.

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?

Description clearly states 'Edit or fuse input image(s) with an instruction' and distinguishes between one image (edit) and two or more (fusion). It also warns that Imagen models are rejected, differentiating from sibling tool generate_image. Purpose is specific and 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?

Provides explicit usage guidance: one image = edit, two or more = fusion. Warns against using Imagen models. Lists parameters with defaults and behavior. Could be more explicit about when not to use (e.g., text-to-image use cases), but adequate.

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