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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive; the description adds substantial context beyond annotations: data sources (SEC EDGAR/XBRL, FAERS, FDA), specific financial metrics, off-calendar fiscal year handling, sorting by primary metric, and output format including citation URIs. No contradiction.

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 lengthy but every sentence serves a purpose: query triggers, core purpose, preference rule, type-specific details, sorting behavior, and return format. It is front-loaded with examples but remains well-structured and information-dense for a tool with two modes and multiple data sources.

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?

No output schema exists, yet the description explains return contents (paired data, citation URIs) and sorting behavior. It also covers data provenance and edge-case handling (off-calendar fiscal years), providing a complete picture for the agent to invoke the tool correctly without further probing.

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 for both parameters. The description enriches this by explaining how 'type' determines data pulled (10-K metrics vs FAERS/FDA counts) and clarifying the 2–5 entity limit for 'values'. This adds meaningful context beyond the raw enum/array definitions, though the schema already covers basics.

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 this tool performs 'side-by-side comparison of 2–5 companies or drugs in ONE parallel call' and supports comparison/ranking queries like 'X vs Y' and 'which is bigger'. It distinguishes itself from single-entity alternatives by emphasizing it replaces 8–15 sequential lookups, aligning with sibling entities like entity_profile.

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 instructs to 'ALWAYS PREFER over sequential single-pack lookups when comparing entities', giving clear when-to-use guidance. It also describes type-specific behavior (company vs drug) and output sorting, but does not explicitly name sibling alternatives or exclusion cases, leaving minor room for improvement.

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