compare_images

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

With no annotations provided, the description carries the full burden of disclosure. It states the return behavior ('返回逐项对比结果') and the scope of 2-4 images, but it does not mention any side effects, permissions, or limitations, which are less critical for a read-only analysis tool but still relevant.

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 concise sentence in Chinese, front-loaded with the core purpose and immediately followed by concrete use cases and return type. Every phrase adds value, with no redundancy or filler.

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 no output schema and no annotations, the description provides sufficient context: it explains what the tool does, how many images to use, common scenarios, and the nature of the output. It lacks explicit output structure but is adequate for an agent to select and invoke the 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 100%, so the input schema already describes all parameters (detail, images, question). The description does not add significant parameter-level detail beyond the schema, so the baseline score of 3 is appropriate.

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 a specific verb and resource: '多图对比分析' (multi-image comparison analysis), with concrete use cases (A/B screenshot comparison, design mockup consistency, multi-frame analysis). It distinguishes from sibling tools like describe_image/analyze_image by emphasizing multiple images and comparison-specific tasks.

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 gives example use cases that imply when to use the tool (A/B testing, design consistency, multi-frame analysis), but it does not explicitly state when not to use it or mention alternatives. The usage context is clear but not prescribed with exclusions.

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