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

Annotations already declare readOnlyHint, idempotentHint, and no destructive behavior. The description adds valuable context: data sourced from official immigration authorities and a practical tip about using the most favorable passport. It does not cover error conditions or response volume, but given annotation coverage, this is sufficient.

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, tight paragraph. It front-loads the core purpose, then lists output details and usage guidance without redundant phrases or filler. Every sentence contributes value.

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 there is no output schema, the description compensates by enumerating exactly what each option includes (visa/permit type, required status, max stay, work allowance, cost, processing time, notes). It also provides source credibility and alternative tools, making it fully self-contained for an agent to decide and invoke.

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?

Input schema covers 100% of parameters, so baseline is 3. The description adds meaningful semantic guidance beyond the schema, particularly the tip that nationality should be the traveller's most favorable passport for multi-nationals, which is not apparent from the field description alone.

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 entry/visa options for a traveller based on nationality, destination, purpose, and duration, and enumerates the output fields. It distinguishes itself from siblings by explicitly naming departi_track_schengen and departi_check_tax for different use cases.

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?

Explicit guidance is provided: 'Use this for "what visa do I need / can I stay N days / can I work remotely here"'. It also names specific alternatives for other needs (90/180-day tracking and tax consequences), making when-to-use and when-not-to-use crystal clear.

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