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

Annotations already indicate read-only, idempotent, non-destructive. The description adds significant behavioral context: for companies it pulls specific financial metrics from SEC EDGAR/XBRL with correct fiscal year handling; for drugs it pulls adverse-event counts, FDA approvals, and trial counts; results are sorted by primary metric; returns paired data with citation URIs. This goes well beyond the 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 moderately long but well-structured. It front-loads example queries and the key usage guideline. Every sentence adds value, though minor redundancy exists (e.g., 'side-by-side comparison' and 'in ONE parallel call'). Overall efficient.

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?

Given no output schema, the description explains return values: paired data + citation URIs. It covers both entity types and notes sorting behavior. It does not detail pagination or per-entity limits, but for a comparative tool this is sufficient.

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 clear descriptions. The description adds value by explaining what each entity type returns (specific financials for company, counts for drug) and that values are tickers/CIKs for company and names for drug. It also notes the max of 5 entities per call.

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 defines the tool as performing side-by-side comparison of 2-5 companies or drugs in a single call, using specific verbs like 'compare' and 'rank'. It distinguishes itself from sibling tools like 'entity_profile', which is likely a single-entity lookup, by explicitly stating it replaces sequential 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?

The description explicitly states 'ALWAYS PREFER over sequential single-pack lookups when comparing entities' and provides example queries indicating when to use (comparing, ranking, head-to-head). It lacks explicit exclusion cases, but the guidance is strong and clear.

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