Create a contact group

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

The description discloses important non-obvious behavior: duplicate names fail with 409 CONFLICT instead of creating a second group, and the response includes resourceName, name, and etag. This adds value beyond the annotations by explaining idempotency failure, uniqueness enforcement, and return payload.

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 compact and front-loaded, with every sentence contributing useful information. It states the action, the return format, the uniqueness constraint, and the next logical step in three sentences without redundancy.

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 single-parameter creation tool with no output schema, the description is complete: it covers what is created, the return value, an important error behavior, and the follow-up tool. An agent has enough information to call this tool correctly and understand the outcome.

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 coverage is 100%, and the name parameter's uniqueness is already documented in the schema. The description reinforces the uniqueness rule and adds the specific 409 failure mode, but it does not need to add more since the schema already captures the parameter meaning.

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 specific verb and resource: it creates a new user contact group (label) and returns it. It also clarifies the resource identifier format, which distinguishes it from sibling tools like create_contact and list_contact_groups.

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 clearly indicates when this tool is appropriate: when a new contact group is needed. It also provides a pointer to modify_group_members for populating the group, giving useful workflow context. It does not explicitly exclude alternatives such as create_contact, but the purpose is unambiguous.

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