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

With no annotations, the description carries the burden. It states the output includes key fields but does not disclose pagination behavior, sorting, data freshness, or error handling. The schema covers limit/offset, but the description adds no behavioral context beyond listing.

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 a single, concise sentence that front-loads the main purpose and key fields. It is efficient but could be slightly more structured (e.g., separating output description from filtering).

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 list tool with 6 parameters and no output schema, the description mentions the output fields but omits pagination details, sorting order, and behavior for empty results. It is adequate but not fully complete given the lack of annotations.

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 description coverage is 100%, so baseline is 3. The description repeats that filtering is possible by cancer type, keyword, or approval date, but adds no new semantic meaning beyond what the schema already provides.

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 explicitly states the tool lists FDA-approved oncology drugs with specific fields (indication, company, approval date, label links). The inclusion of 'oncology' differentiates it from general drug tools, and the filtering options are clearly listed.

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 filtering by cancer type, keyword, or approval date, implying usage for list exploration. However, it does not explicitly state when to use this tool versus siblings like search_oncology or list_clinical_trials, nor does it provide when-not or alternative guidance.

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