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

Annotations already indicate read-only, idempotent, non-destructive. The description adds specific behavioral details: for companies, pulls latest 10-K data with correct off-calendar fiscal year handling; for drugs, pulls FAERS counts, FDA approvals, trial counts. Also mentions sorted results and citation URIs. No contradictions.

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?

Description is a single paragraph but is dense with information. It is front-loaded with trigger phrases. Could be improved with bullet points, but it remains concise without redundancy.

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?

Despite no output schema, the description explains that returns paired data with citation URIs. It covers both entity types' specific data points and the sorting behavior. A bit vague on exact output format, but sufficient for an agent to understand the tool's capability.

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%, but description adds significant context: 'type' maps to data source and specific metrics, 'values' examples with tickers and drug names clarify proper input. The constraint of 2-5 items and the difference between company and drug inputs are well explained.

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 compares 2-5 companies or drugs side-by-side. It lists example query phrasings and specifies what data each type returns (financials for companies, adverse events for drugs). It distinguishes itself from sequential single-pack lookups.

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?

Explicitly says 'ALWAYS PREFER over sequential single-pack lookups when comparing entities.' This tells the agent when to use this tool (comparing entities) and when not to (single entity lookups). Clear context and alternatives provided.

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