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

Beyond the readOnlyHint annotation, the description exposes key behavioral subtleties: buyback authorizations are kept distinct from actual cash spent, data is free from SEC XBRL/filings, and an empty result for a kind is 'not proof it never happened.' This materially prevents misinterpretation.

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 information-dense but efficiently organized: a one-line scope statement, a bulleted explanation of each kind, and a crucial caveat. Every sentence adds value, and nothing is redundant with the schema's enum values.

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 output schema and detailed `kind` semantics make the tool largely self-contained for a read-only query. The main gaps are the lack of explicit meaning for `limit`/`periods` and no guidance on sibling alternatives, which keeps it from being fully complete.

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 `kind` parameter is explained exceptionally well, including aliases and the meaning of each view. However, schema description coverage is 0% and the description does not clarify `entity`, `limit`, or `periods`, so those parameters must still be inferred largely from their names and defaults.

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 opens with a specific resource and scope: 'How a company returns capital to shareholders and changes its share structure.' It then defines each `kind` view so precisely that the tool's purpose is immediately clear and distinct from likely 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?

It gives strong context for selecting among the tool's own `kind` values and a valuable caveat about missing data. However, it does not name sibling tools or explicitly say when to prefer this tool over alternatives such as `get_calendar` or `get_filings`.

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