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

The annotations already declare read-only and idempotent behavior. The description adds value by specifying the return data fields (brand name, company, device description, product codes, GMDN terms, sterilization info, premarket submissions), giving the agent an expectation of what the response will contain. No contradictions with 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 concise and well-structured: three sentences covering the action, the return data, and related tools. It is front-loaded with the core purpose, and every sentence earns its place without unnecessary detail.

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?

With the schema fully documenting parameters and the description covering purpose, return data, and related tools, the definition is largely complete for a read-only search tool. Minor gaps include the absence of guidance on behavior when no parameters are supplied and the lack of direct differentiation from the fda_device_udi_lookup sibling, but these do not significantly impair usability.

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 has 100% description coverage for all 6 parameters, so the description does not need to add much. It lists the searchable fields (brand name, company, product code, DI number) but provides no additional per-parameter semantics beyond what the schema already documents.

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: searching the FDA UDI database by brand name, company, product code, or DI number. It also names related tools for differentiation, though it does not explicitly distinguish from the similarly named fda_device_udi_lookup sibling.

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 mentions related tools fda_device_class and fda_search_510k with their distinct purposes, implying that this tool is for general UDI searches. However, it lacks explicit guidance on when to prefer this tool over fda_device_udi_lookup or when to avoid using it, so usage context is implied rather than fully specified.

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