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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, so the bar is lower. The description adds valuable behavioral context beyond annotations: it is 'a live GET against the public IBGE SIDRA API' and 'Returns a Markdown table.' This tells the agent about network dependence and output format. It slightly redundantly restates read-only/idempotent, but the extra context justifies a 4.

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 longer than average but well-structured: a crisp one-sentence summary, a feature bullet list, brief background on SIDRA surveys, examples, workflow placement, and behavior. Each section earns its place. It could be tightened by removing the survey-list background, but the organization and front-loaded purpose keep it effective.

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?

All three parameters are optional and documented, the workflow is fully laid out, alternatives are named, and the return format is stated ('Returns a Markdown table'). The presence of an output schema further reduces the need for return-value detail. Nothing an agent needs to decide whether and how to call this tool is missing.

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 covers 100% of parameters with descriptions, including default and bounds for limite. The description adds practical examples ('busca="população"', 'pesquisa="censo"', list with no parameters), which reinforce the schema but don't significantly extend it. Baseline 3 is appropriate when the schema does the heavy lifting.

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 opens with a clear verb+resource statement: 'Lists and searches available SIDRA tables.' It then enumerates concrete capabilities (list, search, filter, show code/name) and explicitly positions itself as step 1 of a workflow, distinguishing it from sibling tools like ibge_sidra_metadados and ibge_sidra. The differentiation from wrapper tools is also explicit.

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 description gives direct when-to-use guidance: 'This is step 1 of the SIDRA workflow: find a table code → ibge_sidra_metadados (structure) → ibge_sidra (query).' It also names alternatives and a decision rule: 'For common data, a wrapper is usually easier: ibge_censo, ibge_indicadores, ibge_comparar, ibge_cidades.' This is exactly the kind of routing an agent needs.

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