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

Annotations already indicate readOnly, openWorld, idempotent, non-destructive. The description adds significant behavioral context: it pulls data from SEC EDGAR/XBRL for companies (handling off-calendar fiscal years), and FAERS/FDA/trials for drugs, and sorts by primary metric. No contradictions with 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 front-loaded with common trigger phrases and efficiently conveys key details. Every sentence provides useful information, though it could be slightly more concise without losing clarity.

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?

Without an output schema, the description adequately describes return format (paired data + citation URIs). It covers input constraints, data sources, and sorting behavior, making it complete for an agent to select and invoke the tool correctly.

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%, baseline 3. The description adds meaning beyond schema by explaining what data each type pulls and the expected format for values (tickers/CIKs vs drug names). This adds value for correct usage.

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 lists trigger phrases (e.g., 'Compare X and Y', 'X vs Y', 'which is bigger') and states the tool performs side-by-side comparison of 2-5 companies or drugs. It clearly distinguishes from sibling tools like entity_profile, which provides single entity details.

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 advises 'ALWAYS PREFER over sequential single-pack lookups when comparing entities', giving clear when-to-use guidance. However, it does not explicitly list alternative tools or when not to use it, though the context implies it.

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