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

The description adds behavioral constraints beyond the annotations (readOnlyHint=true, idempotentHint=true, destructiveHint=false). It explicitly states 'Local lookup only — no network access, no legal advice,' which is critical operational context. It also discloses the full set of return fields and the ERROR case for unsupported input, providing transparent expectations without contradicting any annotation.

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 sentences, front-loaded with the core purpose, followed by the output summary and constraints. Every sentence provides essential information without redundancy. The structure is efficient and scannable, ideal for quick decision by an agent.

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 (3 required params, all enums, existing output schema), the description provides complete context: what it does, what it returns (including ERROR case), and its constraints (local lookup, no legal advice). The presence of the output schema means the description doesn't need to enumerate every return field, but it still highlights the key outputs. This is a complete and self-sufficient description.

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% with detailed parameter descriptions and enums for each of the three parameters. The description reinforces the 'jurisdiction pair' and 'data category' but does not add new semantic depth beyond what the schema already provides. This matches the baseline of 3 for well-covered 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?

The description opens with a clear specific verb+resource: 'Cross-border regulatory preflight for agent data flows.' It explicitly states the checks (jurisdiction pair, data category) against a policy matrix and the output verdicts. This clearly distinguishes it from the sibling tools, which handle market scans, tool discovery, receipt verification, and X402 quoting — all different domains.

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 clearly indicates when this tool is used: for regulatory preflight of agent data flows between jurisdictions. It specifies the exact inputs (jurisdiction pair, data category) and the output (verdict, blocked_fields, etc.). While it doesn't explicitly mention when NOT to use it or name alternative tools, the distinct purpose makes the usage context evident. It could have added a sentence like 'Use this before any cross-border transfer to assess compliance' but the context is sufficient.

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