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

The readOnlyHint annotation already covers safety, and the description adds valuable behavioral detail by mentioning the 'sanctioned country' flag, which is part of the tool's output logic. It doesn't contradict annotations and provides additional context without needing to describe return format due to the output schema.

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, front-loaded sentence that conveys both the primary action and the distinguishing flag. There is no redundant or extraneous information, making it efficiently concise.

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 simplicity (1 parameter, read-only, output schema present), the description covers the core behavior. It doesn't mention potential edge cases like private IPs or rate limits, but the output schema handles return values. It is nearly complete, just missing a small note about input format limitations.

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 has zero description coverage, so the description must compensate. It only mentions 'IP address' at a high level and does not clarify accepted formats (e.g., IPv4 vs IPv6) or any constraints. This fails to add meaningful parameter semantics beyond the schema's type/name information.

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 tool's purpose with a specific verb ('Geolocate') and resource ('IP address'), and adds a distinguishing output ('flag whether it is in a sanctioned country'). This differentiates it from sibling tools like detect_vpn or screen_country, which focus on different aspects.

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 a clear use case: geolocating an IP and determining if it falls in a sanctioned country. While it doesn't explicitly name alternatives or exclusions, the specific sanction flag provides sufficient context for when to use this tool over siblings. A clear context with no explicit exclusions earns a 4.

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