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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is known. The description adds extra behavioral details: 'No authentication required' and 'Luhn validated' for credit cards. These go beyond the annotations and inform the agent about accessibility and validation behavior. No contradiction with annotations found.

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 front-loaded with the core purpose and then provides an extensive list of countries and document types. While the country list is lengthy, it is compact and comma-separated, and every piece adds value for international coverage. There is no fluff or repetition.

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 moderate complexity, the description covers the key aspects: what it detects (PII types), where (countries), why (compliance), and accessibility (no authentication). The input schema and output schema (though not shown) handle parameter and return structures. The only minor gap is lack of explicit examples or edge-case handling, but overall it is sufficiently complete.

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 description coverage is 100%, so both parameters ('text' and 'countries') are already well-documented. The description lists countries covered, which complements the 'countries' parameter but does not add new syntax or format details beyond what the schema provides. Thus, baseline 3 is appropriate.

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's function: 'Detect international PII across 30+ document types from 15+ countries.' The verb 'Detect' and specific resource 'international PII' make the purpose unambiguous. The detailed country-specific list (Brazil, USA, UK, etc.) further distinguishes it from generic PII checkers like thinkneo_check.

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 provides clear usage context: 'Required for LGPD/GDPR/HIPAA compliance.' This tells the agent when to use the tool. However, it does not explicitly mention alternatives or when not to use it, so it falls short of a 5. The context is clear enough to guide selection among siblings.

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