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

Annotations already declare this a safe, idempotent, read-only query, so safety is covered. The description adds genuinely useful behavioral context by disclosing the conditional branching: without a tool it returns categories rather than results.

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 sentences, front-loaded with the core purpose and ending with the fallback behavior. Every clause carries information; nothing is redundant.

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 simple single-parameter read tool with full annotation coverage and no output schema, the description conveys enough about what is returned (alternatives or categories). Return shape/format is left unspecified, but that is a minor gap here.

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 schema already documents the parameter as an optional paid-tool name. The description goes further by spelling out the semantic consequence of supplying vs. omitting it (alternatives vs. categories), adding meaning beyond the schema.

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 (devuelve) and resource (alternativas gratuitas a herramientas de pago para buscar trabajo), with concrete examples of the tools covered. No sibling tool overlaps this lookup function, so the scope is unmistakable.

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?

Explains the key usage branches: pass a tool to get its alternatives, or omit it to get the available categories. It gives clear context for invocation, though it doesn't reference any sibling tool as an alternative or state exclusions.

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