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

Annotations declare this is a non-read-only, non-destructive, non-idempotent mutation, and the description adds genuinely useful context beyond that: the caller must be the workspace owner and certain member classes are structurally out of scope. It does not explain what happens on partial failure or whether role changes take effect immediately, so it is not fully complete.

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, front-loaded with the operation, followed by the exclusion rules and the authorization requirement. Every sentence carries information an agent needs; nothing is redundant.

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 four-parameter mutation with no output schema and full schema coverage, the description supplies the key permission and scope constraints an agent needs to call it correctly. Missing only minor behavioral detail such as error or idempotency behavior.

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 each parameter is already documented in the schema, giving a baseline of 3. The description adds only one semantic detail beyond the schema — that 'owner' is not a valid target role — which is largely implied by the admin/member 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?

States a specific verb and resource ('Change the role of an explicitly-granted workspace member'), which clearly scopes the operation to workspace-level explicit members rather than board members. It does not name the closest sibling (update_member_role), so an agent must infer the distinction from scope wording 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?

Gives concrete when-not conditions: owner role cannot be assigned or changed, and org-inherited members are handled on the organization surface. It also states the authorization prerequisite ('Requires the workspace owner'). It stops short of explicitly routing to the sibling tools that handle those excluded cases.

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