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

Annotations already declare destructiveHint=true and idempotentHint=true, so the mutation profile is covered. The description adds genuinely new behavioral context beyond the annotations: the authorization requirement and the specific business rule that blocks demoting the last owner.

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 short sentences, each carrying a distinct fact: the action, the constraint, and the permission gate. Nothing is padded and the action is front-loaded.

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 two-parameter mutation with no output schema, the definition covers action, valid roles, permission requirement, and the key failure mode. It omits only minor details such as error behavior for invalid roles or what state changes are returned, which an agent can reasonably infer.

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 50% — user_id is described but the role enum has no per-value description. The description's role list merely restates the enum, adding no semantics about what each role grants; the baseline 3 applies since the schema already carries the enum.

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?

A specific verb plus resource ('Change a workspace member's role') with the valid role values enumerated inline. It is clearly distinguishable from siblings like invite_member, remove_member, and get_member_access without needing to open 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?

States the prerequisite 'Workspace owners only' and the guardrail 'The last owner can't be demoted', giving an agent clear conditions for calling it. It does not name alternative tools, but the sibling set (remove_member, invite_member) makes the boundary self-evident.

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