user_permissions_create

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

No annotations provided, so description carries full burden. It indicates a write operation and requires confirmation, but does not disclose side effects (e.g., whether existing permissions are overwritten) or specific behaviors like idempotency. The [WRITE] tag and confirm requirement are helpful but incomplete for full transparency.

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?

Single sentence with no wasted words. Front-loaded [WRITE] immediately signals type. Every component (action, target, prerequisites) is packed efficiently. Exemplary conciseness.

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 5 parameters and no output schema, the description adequately covers the tool's purpose and key constraints. It could mention that it returns a UserPermission resource or typical error scenarios, but overall complete for a grant permission tool. Schema covers parameter details.

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%, with all parameters described. The description adds context ('optionally containers') beyond schema, but doesn't significantly enhance meaning for each parameter. Baseline of 3 is appropriate since schema already does the heavy lifting.

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 grants user access to a GTM account and optionally containers, with [WRITE] prefix indicating write operation. It distinguishes from sibling tools like user_permissions_delete, user_permissions_get, etc., by specifying the action (grant) and scope.

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 explicitly notes prerequisites (GTM_MCP_ENABLE_WRITES=true and confirm=true). While it doesn't contrast directly with siblings, the context of granting versus modifying or deleting is implied through sibling names. Slight gap in not specifying when not to use.

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