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

With no annotations, the description carries the burden of disclosing behavior. It states the tool returns current requirements and specifies the domains covered, which gives a clear sense of what to expect. It does not describe output format or limitations, but for a zero-parameter fact retrieval tool, 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, front-loaded sentence with a clear verb and specific enumerations. Every word adds value; no redundant phrasing.

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?

Given the tool's simplicity (no parameters, no output schema), the description covers the key aspects: what it does and what content categories are included. It could mention explicitly that it's not a personalized eligibility check, but that is tangential to the fact-retrieval purpose.

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 no parameters, and the schema is empty. The baseline for zero parameters is 4; the description adds context about the returned content, which is not parameter-related.

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 the tool returns current requirements for Spain's digital nomad visa, enumerating specific content areas (income thresholds, timelines, filing routes, apostille rules). This differentiates it from siblings like check_dnv_eligibility and find_sworn_translators.

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 makes the tool's use case clear: to obtain up-to-date visa requirement facts. It does not explicitly mention alternatives or exclusions, but the context is unambiguous; the sibling tools' names imply different purposes, so no confusion arises.

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