company_facts

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

There are no annotations, so the description carries the behavioral disclosure burden. It adds meaningful context: the data is audited, annual, from XBRL facts, includes fiscal year and filing date, and the result explicitly reports when ADRs lack facts. It does not mention rate limits or response structure, but the key behavioral constraints are disclosed.

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 two sentences and packs in the data source, scope, metric list, and an important limitation without wasting words. The core facts are front-loaded, and the caveat is placed at the end. It earns a 4 rather than 5 because the line break and sentence flow could be slightly tighter, but it is not verbose.

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?

For a simple single-parameter tool with no output schema, the description covers the main return contents and a key edge case. It explains what data comes back, the filing period context, and the ADR limitation. Minor gaps remain around ticker formatting and units, but the description is largely sufficient for an agent to 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 only parameter, ticker, has no description in the schema and the description does not explain ticker format, such as whether to use a plain US ticker like AAPL or a suffix like .US. The ADR caveat hints at ticker selection indirectly but does not define accepted formats or normalization behavior. With 0% schema coverage, the description needed to compensate more.

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 identifies the resource as audited annual fundamentals sourced from SEC EDGAR 10-K XBRL facts. Although it omits an explicit verb like 'retrieves' or 'provides,' the intended operation is unmistakable. The listed metrics (revenue, net income, free cash flow, equity, debt) distinguish it from most sibling tools.

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 gives useful context by stating this is for US filers only, annual data, and free, and it warns that foreign ADRs usually lack US-GAAP facts. However, it does not explicitly state when to prefer this tool over nearby alternatives like analyze_stock or filing_sections, nor does it describe when not to use it beyond the ADR caveat.

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