Corporate calendar

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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered; the description adds substantive context beyond them, namely the equity-only restriction, the explicit error behavior for non-equity symbols, and a concrete inventory of what is returned. It stops short of noting rate limits or how many future events are covered.

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 short sentences, front-loaded with the verb and resource, followed by return contents and then the constraint. Every sentence earns its place with no repetition of the schema or annotations.

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?

An output schema exists, so return-value structure need not be explained, and the description still sketches the payload. The equity-only behavior and the symbol requirement are both covered. The remaining gap is routing guidance relative to the overlapping get_earnings/get_dividends siblings.

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 description coverage is 100% and there is only one parameter, so the schema already documents the symbol format, ISIN support and the 'use search first' fallback. The description's only parameter-adjacent content is the equity-only constraint, which is behavioral rather than semantic; 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?

States a specific verb and resource ('Get upcoming corporate-calendar events for a Yahoo symbol') and enumerates the payload (next earnings date(s) with analyst estimate ranges, next dividend/ex-dividend dates). It is clearly distinguishable from most siblings, though it never contrasts itself with the closely overlapping get_earnings and get_dividends 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?

Usage is implied by the scope: this is the combined calendar view (earnings + dividends). The 'Equity-only' sentence functions as a real exclusion — an ETF/fund/crypto symbol will error — which is useful when-not guidance. However, it names no alternative for those cases (e.g. get_fund_data) and never tells the agent when to prefer this over get_earnings or get_dividends.

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