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

The description goes beyond the readOnly/idempotent annotations by disclosing concrete processing behavior: it validates numeric days, correct URLs, non-empty subjects, and duplicate removal. It also transparently states the price and payment mechanism (x402 with USDC on Base), which is valuable operational context not present in the annotations.

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 short and front-loaded with the core action and expected output. However, the pricing information is stated twice in slightly different formats ('0,02 $ por petición' and 'Precio: 0.02 USD por llamada'), which is redundant and slightly reduces conciseness.

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 conversion tool with no output schema, the description covers the input (CSV with header, max 1 MB), the output (validated JSON), and the cost. It does not specify the exact required CSV columns, but the validation hints ('días', 'URLs', 'asuntos') give enough guidance for an agent to understand the expected structure.

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 schema is minimal (one 'csv' parameter, 100% coverage), so the baseline is 3. The description adds meaningful context by specifying that the CSV represents an onboarding sequence and by implying expected fields ('días numéricos, URLs correctas, asuntos no vacíos'), which helps the agent understand what kind of CSV content is valid.

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 a specific action: send a CSV with an onboarding sequence and receive clean, ordered, validated JSON. The title reinforces the resource ('onboarding email') and output ('JSON listo para importar'), making the tool's purpose distinct from sibling tools focused on requirements, changelogs, geocoding, or backlog tasks.

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 intended use is implied: use this tool when you have an onboarding sequence in CSV and want a normalized JSON version. However, there is no explicit when-to-use or when-not-to-use guidance, nor any named alternative among the sibling tools, so the agent must infer the appropriate context.

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