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

Goes beyond the annotations by detailing what data is fetched (10-K revenue, net income, cash, long-term debt, FAERS counts), how off-calendar fiscal years are handled, that results are sorted by primary metric, and that output includes paired data and pipeworx:// citation URIs. This is rich behavioral context consistent with readOnlyHint.

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 dense yet efficient, front-loaded with examples and core behavior. Every sentence adds value, including the 'off-calendar fiscal years' edge case and the 'replaces 8–15 sequential lookups' performance note. No filler or 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?

Even without an output schema, the description fully explains the return format (paired data + citation URIs), sorting behavior, and data sources for both entity types. It also addresses edge cases like fiscal year variation, making it self-sufficient 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?

The description significantly enriches the schema's parameter documentation. It explains the 'type' enum with detailed data source differences and clarifies 'values' formats (tickers/CIKs vs drug names). The schema already has 100% coverage, but the description adds substantial meaning beyond the basic property descriptions.

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 performs side-by-side comparisons of 2–5 companies or drugs in a single parallel call, with explicit trigger phrases like 'Compare X and Y' and 'rank these companies.' It distinguishes itself from sibling tools by emphasizing it should be preferred over 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?

Provides explicit guidance on when to use: 'ALWAYS PREFER over sequential single-pack lookups when comparing entities' and lists concrete example queries. It also differentiates between company and drug types, telling users exactly what each type pulls, effectively covering alternatives.

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