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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and external-lookup profile is covered. The description adds one useful behavioral detail beyond that: a domain input triggers an implicit resolution step before geolocation. It says nothing about rate limits, data sources, or result accuracy limits.

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?

A single front-loaded sentence with no filler; the input-format clarification earns its place by setting expectations about domain handling.

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 simple two-parameter read-only lookup with full schema coverage and annotations covering safety, this is nearly complete. The one gap is that no output schema exists yet the description does not indicate what geolocation fields are returned.

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%, with both 'target' and 'lang' fully documented in the schema, so the schema does the heavy lifting. The description reinforces the accepted 'target' formats but adds nothing about 'lang' or other parameter semantics beyond the 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?

States a specific verb (look up) and resource (geolocation of an IP or domain), and clarifies accepted input types (IPv4/IPv6/domain). It implicitly distinguishes itself from DNS siblings by noting that a domain is resolved to an address first, though it never names an alternative tool 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?

The description gives no when-to-use, when-not-to-use, or alternative guidance relative to siblings like dns_query, whois_lookup, or domain_report. Usage is only inferable from the purpose statement itself.

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