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

With no annotations, the description carries the behavioral burden; it discloses that statuses transition through scheduled -> released -> corrected and that upcoming_only defaults to true. It does not mention output shape or any limits/rate constraints, but for a read-only calendar tool the disclosed status model is the most important 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 compact and front-loaded: purpose, status behavior, usage condition, and the three meaningful parameters. There is no filler or redundant detail.

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 simple calendar query tool, the description gives enough context: source, coverage, status transitions, and core parameters, while the output schema covers return values. The main missing piece is guidance on the five auxiliary parameters, which prevents full completeness.

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 Args section adds meaning for event, upcoming_only, and limit beyond the bare schema. However, schema description coverage is 0% and five other parameters (agent_id, session_id, payment_token, discovery_source, synthetic_identity) are left undocumented, so the description only partially compensates for the schema gap.

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 identifies a concrete resource ('Official IBGE release calendar for Brazilian macro indicators') and lists the covered indicators, then states the intended query ('when the next release ... is scheduled, or whether a given period has been released yet'). This makes it easy to distinguish from sibling tools like brazil_macro_actual or brazil_macro_surprise, which concern data values rather than the release schedule.

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?

The 'Use when' sentence provides explicit conditions: knowing next release timing or checking whether a period has been released. It does not name alternative sibling tools or state when not to use it, so it stops short of a full 5.

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