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

Annotations indicate readOnlyHint and destructiveHint are both false (non-destructive). The description adds behavioral specifics beyond annotations, such as displaying required consumables for devices and compatible devices for topicals, which gives the agent a clear understanding of the tool's response logic without requiring a separate annotation.

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 concise and front-loaded with the primary purpose. Every sentence provides valuable information: the core function, two behavioral modes, and concrete usage examples. There is no redundant or filler content.

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's simplicity (one parameter, no output schema), the description is complete: it explains what the tool does for both device and topical products, gives concrete examples, and implies the return value is a list of compatible products. No major gaps are present.

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 input schema already provides a complete description of the 'product' parameter (name or SKU), achieving 100% coverage. The description does not add additional parameter-specific semantics beyond the examples, so it meets the baseline for high schema coverage.

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 the tool's function: 'Check which products are compatible with a given product.' It further specifies behavior for devices and topicals, distinguishing it from sibling tools like compare_products or recommend.

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?

Explicit usage context is provided with customer-facing example questions: 'what gel do I need with MIRA?' or 'does this serum work with CryoSculpt?' This clearly signals when to use the tool, though it does not explicitly mention when not to use it or alternative tools.

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