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

With no annotations, the description fully discloses behavior: source (8-K filings), estimation logic (last year's date plus 52 weeks, with basis), default window (today to 14 days), max window (120 days), status filter, and that it returns dates only. This is unusually rich for a description and covers all key behavioral aspects.

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, each dense with information, with the core purpose front-loaded. No filler or repetition.

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?

The description covers the two modes, date windows, status, and output scope ('Dates only'), which is sufficient for an agent to invoke correctly. The exact return format (array vs objects) is not specified, but the statement 'Dates only' gives adequate guidance.

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 description explains the ticker mode (historical plus estimate), the from/to defaults and max, and the status meanings, adding value beyond the schema. It does not explicitly describe the limit parameter, but that is trivial; overall it compensates for the 40% schema gap.

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 the tool provides earnings calendar dates from US companies' 8-K filings, distinguishing ticker mode (historical since 2023 plus estimate) from calendar mode. It explicitly notes 'Dates only, no EPS or consensus,' which sharpens its purpose against siblings like economic_calendar and corporate_events.

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 explains the two usage modes (with ticker vs without) and the meaning of date window and status parameters, giving clear context for when to call it. However, it does not explicitly name alternatives or state when not to use this tool, so it falls short of a 5.

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