diff_images

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

No annotations exist, so the description must cover behavioral traits. It explains the output (3-panel composite with red highlights) and parameter effects (threshold as noise filter). However, it does not disclose return type, file system side effects, image format requirements, or error behavior.

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 concise: one sentence for the main purpose, followed by a clean bullet list of parameters with clear roles. No redundant information.

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?

With 4 parameters, no output schema, and no annotations, the description provides adequate but incomplete context. It explains the composite output and parameters but omits return format, file requirements, and potential pitfalls. Not fully comprehensive for a standalone 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 0%, so the description must add meaning. It does so by explaining each parameter's role: image_path_a as baseline, image_path_b as changed, threshold for noise filtering, tile_size for panel dimensions. This adds significant value beyond the bare 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?

The description clearly states the tool's function: 'Compare two images and produce a 3-panel composite'. It explains the layout and the diff visualization, making the purpose immediately obvious. It distinguishes itself from sibling tools (mostly 3D modeling) by being the only image comparison tool.

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?

No explicit guidance on when to use this tool versus alternatives like 'compare_reference_image'. The description implies use for visual diffing, but does not provide context, prerequisites, or exclusion criteria.

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