create_geographic_access_custom_region

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

Annotations already mark the tool as readOnlyHint=false, destructiveHint=true, and openWorldHint=true, so the description does not need to restate those. It adds useful behavioral context about ownership and permission requirements, but it does not explain what destructive side effects may occur when creating a region or whether it can overwrite/replace existing configurations.

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 short and efficient, three sentences with no filler. It opens with the overall purpose, quickly narrows to the specific creation action, and then lists the critical constraints. Every sentence contributes useful information.

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?

The description provides key constraints and permission requirements, but leaves gaps around parameter details, side effects, and the meaning of a custom region in the broader geographic access model. It is adequate for basic invocation but not fully complete for an agent that has no other context, especially given the low schema description coverage and the absent output schema.

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 only 25%, with only customerContext described. The description does not clarify the meaning of name, countryCodes, or X-Tenant-Id. It provides high-level context about country-based access and tenant ownership, but does not compensate for the lack of parameter-level documentation in 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?

The description states a clear action ('Creates a custom region') with a specific resource ('custom region owned by the authenticated tenant'). It also provides meaningful context ('country-based access to tenants in your customer hierarchy') that distinguishes it from the many get/list/update/delete geographic access sibling tools.

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 explicit prerequisites: the tenant must be a customer-hierarchy root and the caller must have the UsersManager permission. It does not explicitly state when to use this tool versus alternatives, but the creation purpose and conditions are clear enough for an agent to select it appropriately.

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