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

Annotations already declare readOnlyHint=true and destructiveHint=false, so no side-effect warning is needed. The description adds useful behavioral context beyond annotations by stating that returned products include available in-stock sizes, pricing, and verified purchase URLs with a concrete URL format. This helps the agent set expectations about the result set without contradicting the annotations.

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, dense sentence that front-loads the core operation ('Search PoloPan products using image_url') and then adds the most important output expectations. No words are wasted, and it avoids repeating schema details that are already available.

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?

Given the tool has 11 parameters, 100% schema coverage, an output schema, and read-only annotations, the description supplies enough context to invoke it with confidence. It names the required input, indicates optional filters, and summarizes return value characteristics. It could be slightly stronger by explicitly naming when to prefer this over image_upload or text search, but that gap is partially addressed by the tool name and sibling list.

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%, and every parameter already has a meaningful description, so the baseline is 3. The tool description only says 'optional filters' without enumerating them, but that is acceptable because the schema fully documents each filter. It does not reveal additional parameter semantics beyond the 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 states a specific verb and resource: 'Search PoloPan products using image_url'. It also distinguishes itself from siblings like products.search.text and products.search.image_upload by explicitly tying the search method to an image URL. The mention of returned data (in-stock sizes, pricing, purchase URLs) makes the purpose concrete.

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 this tool is for searching when an image_url is available, and optional filters can refine results. It does not explicitly contrast with products.search.image_upload or products.search.text, so it stops short of giving explicit when-not/alternative guidance. Still, the context is clear enough for an agent to select it among the image-related search siblings.

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