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

Annotations already declare destructiveHint=true, readOnlyHint=false, and idempotentHint=false, so the safety profile is covered. The description adds nothing beyond that: no note on what a destructive role downgrade does, no required permissions, and no mention of the optimistic-concurrency/retry behavior implied by expectedAclVersion and idempotencyKey. It also sits in tension with the schema, which demands an idempotencyKey while annotations claim idempotentHint=false.

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 no filler; the key scoping constraint ('direct user') is front-loaded. It is efficient rather than padded, though the brevity contributes to the gaps elsewhere.

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 destructive mutation with concurrency control and an idempotency contract, the description omits permissions, preconditions, and the concurrency meaning of expectedAclVersion. An output schema exists, so return values need not be described, but the calling contract is still under-specified.

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 only 20% (just idempotencyKey), so the description must compensate, and it does not. It never explains the role enum (viewer/editor/manager), what expectedAclVersion guards against, or that sheetId is a UUID, leaving four of five parameters semantically bare.

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 ... sheet role') and scopes it to 'one direct user', which differentiates it from team-level and invitation siblings. It does not name any sibling explicitly, so an agent must still infer routing among sheets_set_team_access, sheets_share_with_email, and sheets_remove_user_access.

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?

The phrase 'one direct user' implies this is for changing an existing single-user grant rather than team access or invitations, giving implied usage guidance. There is no explicit when-to-use/when-not statement, no mention of prerequisites (existing access, admin rights), and no named alternative.

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