compare_screenshots

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

With no annotations, the description carries full burden, but it only vaguely mentions 'can trigger fixes' without explaining the nature, risk, or reversibility. It also doesn't clarify that the tool takes text descriptions, not images, which could mislead. The side-effect of triggering fixes is disclosed but under-specified.

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 short and efficient, but the first sentence is somewhat redundant and could be misleading. It could be restructured to prioritize the tool's actual role.

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 provides a basic workflow context but lacks detail on output, side effects, or prerequisites. With no output schema and no annotations, the description should explain more about what 'structures the findings' yields and what 'trigger fixes' entails.

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 100%, so the baseline is 3. The description adds minimal value beyond the schema, only indicating that the 'differences' field comes from Chat's comparison. It does not enrich parameter meaning.

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 identifies the tool as structuring findings from Chat's visual diff between expected and actual screenshots, and potentially triggering fixes. However, the opening 'Visual diff between expected and actual' is ambiguous about whether the tool performs the diff itself. It is distinguishable from siblings like analyze_image by focusing on structuring differences rather than image analysis.

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 the tool is used after Chat has compared two images and described differences ('then this tool structures the findings'). It gives a clear workflow context but does not mention exclusions or alternative tools.

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