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

Annotations already indicate readOnly/openWorld/idempotent/non-destructive. The description adds valuable context: for company, it pulls LATEST 10-K data with fiscal year handling, and for drug, FAERS data. It also mentions results sorted by primary metric and returns citation URIs, going beyond 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 concise (~100 words), well-structured with front-loaded trigger phrases, and every sentence adds value. No redundancy or fluff.

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 covers return format (paired data + citations), addresses complexity (off-calendar fiscal years), and explains when to use. It provides complete context for an agent to correctly invoke the tool.

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 params. The description enriches understanding by explaining what data each type pulls (e.g., company: SEC EDGAR/XBRL revenue, net income, etc.) and giving concrete examples like tickers for company values. This adds significant value beyond the schema alone.

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 starts with explicit trigger phrases ("Compare X and Y", "X vs Y", etc.) and clearly states the tool performs side-by-side comparison of 2-5 companies or drugs. It distinguishes itself from sequential single-entity lookups, making its purpose unambiguous.

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 says 'ALWAYS PREFER over sequential single-pack lookups when comparing entities', providing clear when-to-use guidance. It also explains the two entity types (company and drug) and what data each pulls, helping the agent decide which to use.

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