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

Annotations already declare readOnlyHint=true, so the bar for behavioral disclosure is lower. The description adds value by specifying a plan requirement for bulk lookups and summarizing the security/geolocation data returned. It does not mention rate limits or invalid IP behavior, but those are secondary for a read-only operation.

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 sentences with no filler: the first states the core function and output domains, the second gives concrete use cases, and the third notes a key prerequisite. Information is front-loaded and every sentence earns its place.

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 read-only bulk lookup, the description covers purpose, use cases, high-level output fields, and a plan prerequisite. Schema covers all input constraints. There is no output schema, but the field list partially compensates. Minor omissions like maximum batch size and error behavior are acceptable given the schema's maxLength and annotation's read-only hint.

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 the schema already documents all parameters including the comma-separated format for ips and the meaning of include, verbose, and include_optional. The description does not add meaning beyond the schema; it only mentions multiple addresses, which the schema already covers.

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 begins with a specific verb and resource: 'Get geolocation and security details ... for multiple IPv4 or IPv6 addresses in one request.' It clearly lists the domains covered (country, region, city, timezone, ISP, threat flags) and differentiates from likely single-IP siblings by emphasizing bulk lookup.

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?

Provides clear context: 'Useful for analyzing lists of IPs, grouping by country/region, or flagging suspicious origins' and notes the prerequisite that a plan must support bulk lookups. However, it does not explicitly name sibling tools or state when to use a single-IP lookup instead, so it stops short of full when/when-not guidance.

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