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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, non-destructive, closed-world). The description adds value beyond that by disclosing the payload contents — old and new amount, percent change, growth streak, and the pre-change safety score — which is meaningful since no output schema exists. It stops short of stating any auth or rate-limit behavior.

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?

A single dense sentence that front-loads the scope and ends with the default window, so nothing is buried. It is slightly overloaded with enumerations and returned fields, but every clause carries information rather than filler.

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 2-parameter, zero-required read tool with no output schema, the description does the heavy lifting by enumerating the returned fields and stating the default time window. The only gap is sibling routing, which is left to inference.

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 both parameters are already documented, including the full enum for kind and the YYYY-MM-DD pattern for week. The description only restates the default window ('last 7 days'), adding no syntax or semantics the schema lacks; baseline 3 is correct.

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 precise verb and resource: every dividend increase, cut, suspension, special dividend, initiation and resumption among U.S.-listed companies going ex in one week. By enumerating all change kinds it implicitly separates itself from the narrower get_dividend_raise_calendar and from get_ex_dividend_calendar, so an agent can route without opening schemas.

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?

Usage is only implied: 'Defaults to the last 7 days' tells the agent the fallback window, but nothing says when to prefer this tool over get_dividend_raise_calendar (raises only) or get_ex_dividend_calendar (all ex-dates, no change data). No exclusions or alternative-routing guidance is given.

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