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

With no annotations, the description carries the full burden and does well: it discloses the pipeline (rule-based detection, local LLM rewrite, re-check), the no-op path that avoids the LLM, that text is not stored, and the $0.01/x402 cost. It stops short of stating the exact return shape (rewritten string vs. structured report), which is the main remaining gap.

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?

One dense paragraph, front-loaded with the transformation and its mechanics, followed by no-op behavior, privacy, and price. Every clause adds distinct information; nothing is repeated from the schema.

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 one-parameter tool with no annotations and no output schema, the description covers cost, data retention, and fallback behavior. Only the precise response format is left implicit, which is a minor omission given it hints that unchanged text is returned.

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 coverage is 100% and the single parameter already documents the expected input language and 4000-char cap, so the description adds no syntax or format detail beyond it. Baseline 3 applies 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?

States a specific verb (rewrites) and resource (Brazilian Portuguese → European Portuguese) plus the concrete transformations applied (vocabulary, gerund → 'a + infinitive', 'você'). An agent immediately understands the transformation without opening the schema.

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?

Implies usage (you have BR Portuguese text you want in PT-PT) and notes the no-op case when text is already PT-PT, but gives no explicit when-to-use/when-not framing and does not mention any alternative among chat-gpt-oss, detetor-ia-pt, margem, or verificar-anuncio.

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