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

Annotations already indicate readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds significant behavioral context: it explains that it fetches data from SEC EDGAR/XBRL or FAERS, handles off-calendar fiscal years, sorts results by primary metric, and returns citation URIs, surpassing the annotation-only information.

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 somewhat verbose with many trigger phrase examples, but it is well-structured: starts with purpose, then usage, then parameter details. Every sentence adds value, though some could be shortened 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?

Despite no output schema, the description explains the return format (paired data + citation URIs) and covers edge cases like off-calendar fiscal years. It thoroughly addresses the complexity of comparing multiple entities across two domains, making it fully informative for correct tool invocation.

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 descriptions for both parameters. The description enriches this by explaining what each type yields (revenue, net income, etc. for company; adverse-event counts for drug) and gives examples for 'values' (tickers, drug names), adding meaning beyond the schema.

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?

Description clearly states the tool performs side-by-side comparison of 2–5 companies or drugs in one parallel call, with explicit trigger phrases like 'compare X and Y' and 'which is bigger'. It distinguishes from sequential single-pack lookups, making the purpose unambiguous and specific.

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', providing strong guidance on when to use it. It also details the two entity types (company/drug) and what data each pulls, helping the agent decide appropriately.

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