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

Annotations mark the tool as read-only and not open-world, and the description adds meaningful informational context: it promises to disclose limitations, coverage, and the collection month of the index. No side effects or data mutations are implied, so there is no contradiction.

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, compact sentence front-loads the tool's subject and lists the covered topics, then closes with a direct usage instruction. Every clause earns its place; there is no redundant restating of the title.

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 parameterless informational tool with no output schema, the description fully specifies the available content: methodology, cities and property types covered, collection month, and limitations. The trigger condition is also included, making the definition self-sufficient.

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 tool has zero parameters and 100% schema description coverage, so no parameter documentation is needed. The baseline for parameterless tools is 4; the description could not add parameter-level value.

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 subject, the A Corrida dos Bairros index methodology, and enumerates exactly what it covers: calculation, cities, property types, collection month, and limitations. This clearly differentiates it from the sibling data-operation 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?

It gives an explicit trigger condition: 'Use quando perguntarem de onde vem o dado' (use when they ask where the data comes from). This is an actionable, unambiguous usage rule that tells the agent the intended context.

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