understand_image

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

Discloses model used, supported formats, size limit, and max_tokens constraints. No annotations provided, so description carries full burden. Lacks explicit mention of read-only nature, but it's implied. Return value described generically.

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 clear sections, front-loaded purpose, and no redundant information. Slightly long but each sentence adds value. Could be more concise by integrating arg descriptions into schema, but acceptable.

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?

Covers input parameters, supported formats, size limit, and usage guidelines. With an output schema existing, return value description is adequate. Does not mention error handling or authentication, but overall complete for tool of moderate complexity.

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?

With 0% schema description coverage, the description fully compensates by explaining each parameter's purpose, format (URL, base64, local path), and constraints (max_tokens default and max). Examples for prompt enhance clarity.

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 it uses Xiaomi MIMO multimodal model to understand images, lists specific use cases (analyze, describe, OCR, recognize), and explicitly excludes non-image files. Distinguishes from sibling tools (audio, video) by media type.

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 when-to-use and when-not-to-use sections, suggests alternative Read tool for non-image files, and gives concrete prompt examples.

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