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

Annotations show readOnlyHint=true, openWorldHint=true, idempotentHint=true, destructiveHint=false, indicating a safe, read-only operation. The description adds value by detailing data sources (SEC EDGAR/XBRL with off-calendar handling for companies; FAERS for drugs) and sorting behavior. 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?

The description is concise but comprehensive, front-loaded with familiar trigger phrases. Every sentence adds value: use cases, data sources, sorting, efficiency, and output citations. No fluff 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?

Given no output schema, the description sufficiently explains return format (paired data + citation URIs) and data fields (revenue, net income, etc.) for companies and drugs. It covers key behavioral aspects and works well with the annotations to provide a complete understanding.

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 descriptive parameter descriptions. The description goes beyond the schema by providing concrete examples (e.g., tickers/CIKs for companies, drug names) and clarifying behavior like off-calendar fiscal year handling, which enhances semantic understanding.

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 immediately states the tool's purpose with common trigger phrases ('compare X and Y', 'X vs Y') and explicitly defines it as a side-by-side comparison for 2-5 companies or drugs. It clearly distinguishes itself from siblings like 'entity_profile' by advising preference over sequential single-entity 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 provides explicit when-to-use guidance: comparisons of entities. It instructs 'ALWAYS PREFER over sequential single-pack lookups', which contrasts with the sibling tool 'entity_profile' for single entities. However, it does not explicitly state when not to use (e.g., for single entity), but the context is clear.

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