Brazilian tax transition calendar 2026-2033

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

No annotations are provided, so the description carries the full burden. It discloses useful traits: the tool returns calendar/transition information per year, is purely informational (describes tax status over time), and importantly discloses the cost at $0.002 USDC via x402 — a concrete behavioral trait agents need. It doesn't describe return format, but for a no-parameter informational lookup this is adequate.

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 a single well-crafted sentence that packs the core purpose (which taxes in force, extinction timeline) and usage context (know whether a tax rule applies) plus the cost disclosure. Zero waste, front-loaded with the most important information. No filler or redundancy.

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 zero-parameter, read-only calendar tool with no output schema, the description is quite complete. It specifies the tax universe covered (PIS/COFINS, IPI, ICMS, ISS), the time range (2026-2033), and the use case. It could describe what the output shape looks like, but given there are no params and no output schema, this is reasonably complete. The cost disclosure is a nice additional detail.

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 schema description coverage is 100%. Per the rubric, 0 params means baseline is 4. The description appropriately explains what the tool 'returns' conceptually (tax status by year, extinction dates), which is the semantic content an agent needs since there's nothing to parameterize.

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 clearly states what the tool does: identifies which Brazilian taxes are in force each year and when specific taxes (PIS/COFINS, IPI, ICMS, ISS) get extinguished. The verb 'which taxes are in force' plus the timing context makes the purpose specific and actionable. It distinguishes itself from sibling tools like tributos_ncm and tributos_busca by focusing specifically on the tax transition calendar across years.

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 clearly states when to use this tool: to know whether a tax rule still applies on a given date. It provides the 'context to know' framing, making the use case explicit. However, it doesn't explicitly name alternative tools to use instead (e.g., for looking up specific NCM codes, use tributos_ncm), though the sibling list makes this somewhat self-evident.

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