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

With no annotations, the description carries the full burden. It does disclose the algorithm and language handling (TF-IDF, ES/EN stopwords) and a concrete cost/auth detail (0.02 USDC on Base, pay-per-use), which is genuinely useful context. However, it says nothing about return format, input length limits, or output ordering.

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?

Two tight clauses: purpose first, then input shape, then the payment tag. No wasted words and the most important information is front-loaded, though the abbreviated notation is slightly cryptic.

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 single-parameter extraction tool with no output schema or annotations, the description covers purpose, method, a rough input shape, and cost. It is missing return-value expectations and confirms neither input type nor limits, leaving it only minimally complete.

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 description claims input is an object '{texto, max?}', but the schema declares 'input' as a plain string described only as 'service input'. This mismatch between the stated shape and the declared type creates ambiguity rather than clarifying semantics, so it does not compensate for the generic schema description.

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 ('Extrae') and resource ('palabras clave') and adds the technique (TF-IDF + stopwords ES/EN), so an agent knows exactly what transformation it performs. It is clearly distinct from generic siblings like 'keywords' in method, though it does not explicitly name or contrast a sibling.

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?

There is no statement of when to use this tool versus alternatives, no prerequisites, and no exclusions. The agent must infer usage purely from the purpose sentence, which is minimal guidance.

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