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

Annotations already declare readOnly, idempotent, openWorld, non-destructive, so safety is covered. The description adds genuinely useful non-schema context: deterministic key behavior (variations map to the same key) and a $0.01 USDC x402 cost per call. It stops short of describing the response shape or handling of unparseable addresses.

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?

Three short sentences, front-loaded with the core action and output concept, followed by the operational tip and cost. Nothing 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?

With no output schema, the description does explain what is returned conceptually (a similarity key) and how to use it, and it discloses cost. Minor gaps remain around error behavior and the exact response field name, but an agent has enough to call it correctly.

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?

Only one parameter and schema coverage is 100% (it documents 'Full international address string' with an example). The description's 'any country's format' reinforces locale-agnostic input but adds little beyond the schema's own wording; 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?

States a specific verb (generates a similarity key) and resource (global/international address), plus the deduplication purpose. The 'international / any country's format' framing implicitly separates it from domestic match siblings like interzoid_address_match_advanced, but no sibling is named explicitly.

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?

Gives concrete when-to-use guidance: 'Group on the key to deduplicate international customer, supplier, and location records.' It does not exclude or route to alternatives (e.g. address_parse or address_match_advanced), so guidance is clear but not complete.

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