Lookup IP

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, establishing a safe, read-only operation. The description adds value by specifying what data is returned (geolocation, ISP, ASN, etc.), providing behavioral context beyond annotations.

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 a single sentence that conveys all necessary information without any redundancy or unnecessary words. It is front-loaded with the action and resource, followed by the key outputs.

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?

Despite lacking an output schema, the description lists the main outputs (geolocation, ISP, ASN, reverse DNS, reputation indicators), which is sufficient for the agent to understand what the tool returns. The tool is simple and the description covers its purpose well within the context of its siblings.

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?

The input schema already fully describes the single parameter 'ip' with a clear description ('IPv4 or IPv6 address to investigate') and 100% coverage. The tool description does not add additional meaning to the parameter beyond what the schema provides.

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 verb 'Look up' and resource 'an IP address', and lists specific outputs (geolocation, ISP, ASN, reverse DNS, reputation indicators). This distinguishes it effectively from sibling tools, none of which perform IP lookups.

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 implies usage when needing IP geolocation or reputation data, but does not explicitly state when to use or not use this tool, nor does it reference alternatives. Since the tool is straightforward, the implied usage is acceptable but lacks explicit guidance.

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