Roles: permissions add

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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false, so the mutation/safety profile is covered externally. The description adds nothing beyond that: it does not say what happens if a permission already exists, whether the addition is idempotent, or whether elevated authorization is required.

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?

A single short sentence with the action front-loaded and zero filler. It is efficient, though its extreme brevity is part of why other dimensions are thin rather than a virtue here.

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?

This is a simple three-parameter mutation tool with full schema coverage and no output schema, so little is strictly required. Still, for a mutation on role permissions, the absence of any note about idempotency, authorization, or relationship to the remove/list siblings leaves a visible gap.

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 100%, so all three parameters (role_id, entity, actions) are already documented in the schema, including the comma-separated action values and the 'read' default. The description adds no parameter-level meaning beyond that, so the baseline 3 applies.

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 combination ('Add entity permissions to a role'), which is unambiguous about the action and target. However, it does not differentiate from the closely named siblings roles_permissions_remove and roles_permissions_list, leaving the agent to infer the distinction from names alone.

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?

There is no guidance on when to use this tool versus roles_permissions_remove or roles_permissions_list, nor any stated prerequisites such as required permission level or whether the role must already exist. The agent gets no context beyond the one-line purpose.

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