tool_edit_image

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

With no annotations, the description carries the full behavioral burden. It discloses the mode taxonomy and that some modes are mask-guided versus prompt-driven, which is useful context, but says nothing about side effects (does it overwrite the base image or write only to output_path?), auth/API-key requirements, cost, or latency. That leaves meaningful behavioral gaps for a mutation tool with zero annotation coverage.

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?

Two sentences, zero waste, with the capability enumeration front-loaded and the disambiguation clause placed last. Every phrase earns its place and nothing is repeated from the schema.

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 is adequate for identifying and selecting the tool, and the nested schema covers parameters well. However, with no annotations and no output schema, it omits what the tool returns or where results land, and the requirement that mask-required modes need a mask is only discoverable in the schema. For a file-producing edit tool this leaves a gap.

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 top-level coverage metric is 0% because the single 'params' wrapper is undocumented, but every nested property (prompt, edit_mode, model_name, mask_image_path, etc.) carries a rich schema description, so the schema itself does the heavy lifting. The description adds no parameter-level detail beyond what the schema already provides, which is the expected baseline when the schema is self-documenting.

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?

States a specific verb and resource ('Image editing via Gemini image models') and enumerates the concrete sub-capabilities: mask-guided inpaint/outpaint, background swap, product image, and mask-free prompt-driven edit. It also names the sibling it is not (tool_transform_image), so an agent can distinguish it without opening a schema.

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?

Explicitly routes free-form natural-language transforms (style transfer, scene rewriting) to tool_transform_image, giving a clear selection condition. It stops short of covering the other plausible alternatives (tool_generate_image, tool_analyze_image, tool_upscale_image) or stating when this tool should not be used.

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