cached_user_group_memberships_add

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

With no annotations, the description carries the full burden of behavioral disclosure. It does state that the tool is a write operation requiring 'Write' on 'Security', which is useful. However, it says nothing about cache semantics, idempotency, or side effects despite the 'cached' prefix in the tool name.

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 two concise sentences with no filler. The action is front-loaded, followed immediately by the required permission, making it efficient and easy to parse.

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 simple two-parameter mutation with no output schema and no annotations, the description covers the core action and authorization requirement. Missing details such as return value or caching behavior are minor but would round out an otherwise adequate definition.

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 0%, so the description must add meaning to the parameters. It clarifies that userId and groupId are the two sides of the membership, but this is largely inferable from the parameter names and tool name. It does not explain constraints, referential integrity, or duplicate behavior.

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 uses a specific verb ('Create') and resource ('user–group membership'), and states the required permission. It clearly indicates the operation being performed, but it does not explicitly distinguish this tool from the sibling add_groups_for_user, which also creates user–group memberships.

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?

No guidance is provided about when to use this tool versus alternatives such as cached_user_group_memberships_add_groups_for_user or the get/delete variants. The only extra information is a permission requirement, which is a prerequisite rather than a usage condition.

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