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

Beyond the readOnly/idempotent/non-destructive annotations, the description discloses that results are based on official calendars, scheduled events only, that it does not predict direction or include unscheduled news, and that an empty list is returned when nothing exists. This adds meaningful context about what the tool does and does not do, strengthening the agent's understanding of its 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?

The description is front-loaded with the core purpose, then moves to usage, then limitations. It is slightly longer than necessary but each paragraph delivers distinct value (purpose, when-to-use, supported risks, behavioral caveats, empty-list behavior). No sentence is wasted, though it could be tightened by merging the risks list with the usage line.

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?

Given the presence of a complete output schema, clear annotations, and a description that covers the tool's returns (empty list), limitations (scheduled only, no predictions), and supported event types, nothing essential is missing for an agent to call and interpret results correctly. This is a fully self-contained definition.

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 input schema already has 100% coverage with clear descriptions for both parameters (instrument, horizonHours including default and max). The tool description adds little to parameter meaning; it reinforces the 'future time window' concept and gives examples, but the schema does the heavy lifting, so baseline 3 is appropriate.

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 uses a specific verb ('retrieve'), a clear resource ('known scheduled macroeconomic and central-bank risks'), and scopes it to a future time window and supported FX instruments. It also gives concrete example user queries ('what could move EURUSD', 'what is happening in the next 24 hours'), making the tool's intent unmistakable and distinct from sibling tools like get_event_context or get_market_reaction.

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?

Explicitly states when to use the tool with a list of example phrasings, which is very helpful. However, it does not mention when NOT to use it or name alternative sibling tools for different scenarios (e.g., historical reactions), so it falls short of the full 'when/when-not/alternatives' bar.

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