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

Annotations already declare destructiveHint=true and idempotentHint=true, so the agent knows this is a destructive, repeatable mutation. The description adds no behavioral context beyond the basic mutation itself: it does not explain what access may be lost when a role is downgraded, what permissions are required, or what side effects occur. With annotations covering the safety profile, this is a minimal addition.

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 definition is a single front-loaded sentence with no wasted words. Its terseness is efficient, though it comes at the cost of the missing details noted in other dimensions.

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?

The output schema covers return values, but this is a destructive mutation with an entirely undocumented 'id' parameter and no explanation of permission requirements or access-change effects. For a two-parameter destructive update with 0% schema coverage, the description is not complete enough to guide correct invocation confidently.

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 0%, so the description must compensate for two undocumented parameters. It references 'role' generically but does not explain the 'id' parameter, the accepted role values, or any constraints, leaving the schema to carry meaning it does not actually provide.

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: 'Change' an existing access grant's 'role'. This clearly distinguishes it from sibling operations like invite_share and remove_share by implying modification of an existing grant rather than creation or deletion. It does not explicitly name those siblings, so it falls short of a 5.

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?

Usage is implied: use this when an existing share's role needs to change. However, there is no explicit when-not guidance, no mention of prerequisites such as admin permissions, and no direct comparison to invite_share or remove_share for disambiguation.

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