fda_drug_labels

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

Annotations already establish read-only, open-world, and non-destructive behavior, so the safety profile is covered. The description adds useful context about queryable fields and count fields, but it omits return-format details and pagination/rate-limit behavior, so the annotations carry most of the behavioral burden.

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 purpose is front-loaded and every block (content, examples, count fields) serves a distinct purpose. It is slightly long, and the 'Count fields' line is cryptic without an explanation of how it is used, but overall there is no waste.

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 two-parameter search tool with 100% schema coverage and no output schema, this description gives enough to invoke it correctly: resource, content, query syntax examples, and count fields. It does not explicitly explain what the returned label records look like, but the description is otherwise complete for the search use 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?

The schema descriptions are 100% covered, so the baseline is 3. The description goes beyond the schema by giving concrete search syntax examples (e.g., 'openfda.brand_name:"Tylenol"', '_exists_:boxed_warning', range syntax) and listing count fields, which meaningfully clarifies how the search parameter behaves.

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 opens with a specific verb and resource: 'Search FDA drug product labeling (package inserts / prescribing information — SPL).' It also lists the label sections it covers (indications, warnings, boxed warnings, etc.), which clearly separates it from sibling adverse-event, recall, and approval tools even without naming them.

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 examples convey when this tool is useful (e.g., looking up a brand's labeling, finding labels with boxed warnings, filtering to prescription drugs), so usage is implied rather than explicit. It never names alternatives or says when not to use it, unlike a direct comparison to fda_drug_events or fda_approved_drugs would.

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