Compare Financials Across Companies

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

With only readOnlyHint provided, the description carries the rest and does so well: it discloses the return shape (one row per ticker, latest-restated value), the handling of tickers with no data (listed separately), and a critical caveat that fiscal year/period follow each company's own calendar so rows may span different calendar months. This is substantial behavioral context beyond the 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?

Three sentences, front-loaded with the core purpose and then the return semantics and the fiscal-calendar caution. Each sentence earns its place, though the NVDA example adds some length beyond the minimum needed.

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?

With no output schema, the description correctly picks up the burden of explaining return values, including row structure and missing-data behavior, and flags the fiscal-calendar trap. It omits pagination/result-size behavior, but for a bounded max-25 comparison this is a minor gap.

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%, so parameter documentation is already handled (baseline 3). The description adds interpretation the schema does not: it clarifies that fiscalYear/fiscalPeriod resolve against each company's own fiscal calendar and points the agent to the Period End column, which meaningfully aids correct use of those two parameters.

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 states a specific verb and resource — 'compare one financial concept across several companies for the same fiscal period' — and labels it as peer comparison. This clearly distinguishes it from the sibling GetFinancialFact (single-company lookup) without needing to open either schema.

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?

It establishes clear context for when to reach for this tool (peer comparison of a single concept across multiple tickers for one period). However, it never explicitly names the single-company alternative or states exclusions, leaving the agent to infer the boundary from the sibling name alone.

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