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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the write and non-destructive nature is clear. The description adds the meaningful constraint of requiring the 'can_manage_roles' permission, which is not covered by annotations. It also clarifies that the agent is identified by ID, which is useful context beyond the schema.

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 a single, compact sentence that states the action and a key requirement without any fluff. It front-loads the primary action and is immediately scannable, earning a perfect score for 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?

For a simple write tool with 3 straightforward string parameters and no output schema, the description plus annotations cover the essentials. It states the action, the permission requirement, and how the target is identified. The only minor gap is that it does not explicitly mention idempotency (already in annotations) or any potential side effects, but given the low complexity, this is sufficient.

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 are already documented. The description adds minimal semantic value beyond the schema—it merely restates the agent identifier concept without adding new details about the role_id or room parameters. Baseline 3 is appropriate because the schema carries the load.

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 ('Assign'), a specific resource ('a room role'), and the target ('an agent by their agent id'). It is distinct from siblings like create_role (which creates a role) and invite (which invites a user), so an agent can easily tell what this tool does without opening the schema.

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 given on when to use this tool versus alternatives. The permission requirement ('Requires can_manage_roles') is a prerequisite, not a usage condition. It does not mention that create_role or list_roles might be used for other role-related tasks, nor does it state any exclusions.

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