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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds useful context that this maps to the Photon GraphQL field 'medicationFromNdc', but does not disclose behavior on no-match or the shape of the result.

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?

Two short sentences, zero filler, with the core lookup purpose and the API mapping front-loaded.

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 idempotent lookup with no output schema, the definition is largely sufficient and the GraphQL reference helps an agent map it. It stops short of describing the returned medication data or the not-found case.

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 coverage is 100% with a single required parameter, so the schema carries the burden; baseline is 3. The description adds only that the NDC is 11-digit, a marginal clarification over the schema's own pattern.

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?

States a specific verb ('Find') and resource ('the medication') with a clear lookup key (package NDC). It is distinguishable from search_medications and list_medication_packages because it performs an exact single-item lookup, though it does not explicitly name those 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?

The word 'matching' implies exact-match retrieval by NDC, which is implied usage guidance. However, it never states when to prefer this over search_medications or list_medication_packages, nor what to do when the NDC is unknown.

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