Get a product's label photo

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

The annotations already establish readOnlyHint and openWorldHint, so the description adds non-obvious behavioral context: images are token-expensive, the photo may not show the panel, and label reading is not a substitute for physical packaging. No contradiction with 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?

Four sentences, front-loaded with the purpose and trigger condition, followed by cost and reliability caveats. Every sentence earns its place; nothing is redundant 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 one-parameter read-only tool, the description covers what it returns, why to use it, when to call it, and important limitations. It does not specify the exact image response format, but the description's clarity is sufficient for correct invocation.

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?

The single required parameter 'sku' is already fully described in the schema with 100% coverage, so the description does not need to repeat parameter details. It adds usage context around ordering one product at a time but no additional parameter semantics, matching the baseline.

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 ('Return') and resource ('product's packaging photo'), and explains its purpose: to surface details the API does not publish, especially ingredients and allergens. This clearly differentiates it from get_product and other siblings.

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?

It gives an explicit trigger condition: call when get_product reports allergens or ingredients as 'notStated' and the answer matters. It also provides cost-driven usage constraints (one product at a time, only when needed) and a caution that photos may not be sufficient for allergy decisions.

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