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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuine value by enumerating the returned content (median m²/value by type since 2024, series since 2006, top-selling buildings), though it says nothing about what happens when a street has no records.

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 what the tool returns, followed by a usage example and an edge-case rule. No filler and nothing repeated.

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?

With no output schema, the description does the work of telling the agent what comes back, which is the main completeness burden here. The remaining gap is operational: no mention of data recency/lag in ITBI records or behavior for streets with sparse sales.

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 the schema already documents both rua and bairro, including bairro's disambiguation role. The description's note about homonymous streets largely restates what the schema says, adding only the instruction framing rather than new meaning.

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 and scope: ITBI sales on a single street in São Paulo, returning median m² and value, a series from 2006, and the buildings with the most sales. That granularity implicitly separates it from vendas_bairro and vendas_predio, but no sibling is named explicitly, so an agent must infer the boundary.

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 supplies a concrete triggering question ("qual o m² na Rua Oscar Freire?") and a handling rule for ambiguous input (pass bairro for homonymous streets). It stops short of stating when to prefer a sibling such as comparaveis_endereco or vendas_bairro instead.

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