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

Annotations already declare read-only/idempotent behavior. The description adds valuable context: 'Advisory only, not tax advice', the US citizenship worldwide-obligation note, and a detailed 'Returns' list describing what the tool reveals. This goes beyond basic safety flags.

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 moderately long but front-loaded with a clear purpose statement. It then provides a structured output list, a caveat, usage examples, and a citizenship note. Each sentence adds value and none are 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 complex tool with 9 parameters and no output schema, the description compensates well by enumerating return values, usage intent, advisory status, and a critical legal caveat. It essentially covers all key behavioral aspects an agent needs for correct tool selection.

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 parameter descriptions are already well detailed (e.g., nationality vs taxResidence, yearToDateDays). The description does not add significant meaning per parameter; it mostly reiterates concepts like day counting without specifying syntax or format. Baseline 3 applies.

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 uses a specific verb ('Assesses') and clearly identifies the resource: tax-residency risk and double-tax-treaty position. It distinguishes from sibling tools (visa, schengen tracking) by focusing on tax analysis and enumerates concrete outputs (threshold, treaty provisions, special regimes, US-specific context).

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 use cases are provided via quoted examples ('will staying here make me tax resident / what does the treaty say / how are my days counted'). There are no explicit exclusions or named alternative tools, but the context is clear enough to guide tool selection among siblings.

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