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

The annotations already cover the safety profile (readOnlyHint=true, idempotent, non-destructive, closed-world), so the bar is lower. The description adds real value by disclosing the three-part payload and the analytical ratios, but it omits the recency window or total count for the event list, currency/units, and ordering.

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?

It is a single, front-loaded sentence that leads with the primary deliverable (the event list) and then the supporting statistics. It is dense but every clause carries distinct content; only the stacked parenthetical enumerations make it slightly heavy.

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?

Because no output schema exists, the description has to carry the return contract, and it does so by spelling out all three result components. The remaining gap, how far back the event list runs and how it is ordered, is minor for a read-only lookup tool.

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?

With one parameter and 100% schema description coverage, the schema already fully documents 'symbol', including the 6-digit code format and the workaround via search_stocks. The description adds nothing further about the parameter, so the baseline of 3 applies.

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 names a specific resource (recent major disclosures: contract awards, rights issues, dividends, buybacks, litigation) and states exactly what is returned: event-classified list, 12-month counts/amounts by type, and 30-day frequency versus baseline. An agent can tell this is an event/statistics feed, but the description never distinguishes it from plausible siblings like get_caution_signals or get_news_summary.

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?

There is no explicit when-to-use or when-not-to-use guidance. The only routing hint sits inside the symbol parameter ('use search_stocks first to find the code'), which guides parameter preparation rather than tool selection, so an agent has to infer this tool's niche from the description alone.

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