zitadel_create_user_grant

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

Annotations already declare the write/non-idempotent/non-destructive profile, so the bar is lower. The description still adds genuine behavior beyond them: pre-grant validation that roles exist in the project and drift-flagging for non-standard keys. It omits what happens on validation failure or duplicate grants, hence 4.

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?

Three tight sentences, front-loaded with the core action before the role-model guidance. Every sentence carries information; the only marginal cost is the internal 'v2 AuthorizationService' reference, which is closer to implementation detail than agent-facing guidance.

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 3-parameter, 100%-covered schema with annotations present and no output schema, this is largely complete: it covers purpose, validation behavior, and role conventions. Error semantics (role not found) and non-idempotency consequences are the remaining gaps but are not essential to invoking it correctly.

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%, so the baseline is 3, but the description adds meaning beyond it by explaining the consequence of non-standard roleKeys ('allowed but flagged as drift') and reinforcing the admin/standard model. Nice added semantic layer over 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?

Specific verb+resource: 'Assign project roles to a user' clearly separates it from zitadel_create_project_role (which defines roles) and zitadel_remove_user_grant (which reverses this). The 'v2 AuthorizationService' detail anchors it further. It stops short of explicitly naming a sibling for contrast, keeping it at 4.

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?

Provides a preference rule for role keys ('prefer admin/standard') but gives no when-to-use context relative to alternatives such as zitadel_grant_org_manager or zitadel_create_project_role, and no prerequisites (permissions, project existence). Usage is implied rather than scoped.

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