describe_image

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

With no annotations, the description carries the full burden. It discloses that the tool accepts various image sources and returns a text description, implying read-only behavior. However, it does not mention potential side effects, error handling, or network requirements for URLs, which are meaningful gaps for full transparency.

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 that front-loads the action and result, then lists the input sources. Every word is necessary, and there is no redundancy.

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 simple single-image description tool, the description is adequate. It covers the core purpose and input sources, and the presence of a rich output schema and 100% parameter documentation fills in the remaining details. It omits mention of prompt customization, but that is captured in the schema.

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 description coverage is 100% for all three parameters, so the baseline is 3. The description adds no new parameter semantics beyond what the schema already documents; the mention of input sources duplicates the image parameter's description.

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 uses the specific verb '识别' (recognize) with the resource '一张图片' (an image), clearly stating it returns a text description. It also enumerates the three accepted input sources (local path, URL, data URL), which effectively distinguishes it from sibling tools like describe_images_in_folder and describe_pasted_images.

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 conveys that this tool is for recognizing a single image from local path, URL, or data URL, which implies when to use it. It does not explicitly name sibling tools as alternatives, but the context is sufficiently clear. The auto-detection of URL vs. local path in the schema further supports this.

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