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

Annotations already declare destructiveHint=true and idempotentHint=true, so the description doesn't need to restate those. The description adds useful context: it requires administrative access and operates on an existing member's access to a single authorized project. It doesn't detail side effects (e.g., whether revoking removes the member entirely), but the annotations cover the key behavioral traits.

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, dense sentence that front-loads the core action and includes the key access requirement. No wasted words.

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 tool has an output schema, so return values are already documented. The description covers the essential context: what it does, the access requirement, and the scope ('one authorized project'). It doesn't mention edge cases like what happens when a member is already assigned or unassigned, but the idempotentHint annotation covers idempotency. This is complete enough for an agent to select and invoke it correctly.

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 the schema already documents all three parameters. The description adds minimal parameter-level meaning beyond the schema, but it does clarify the overall operation (grant/revoke) and the 'authorized project' constraint. Baseline 3 is appropriate because the schema carries the heavy lifting.

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 ('Grant or revoke') and resource ('an existing team member's access to one authorized project'), and clearly distinguishes this from sibling tools like add_team_member and remove_team_member. It also notes the administrative access requirement, which adds precision.

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 description clearly indicates when to use this tool: to grant or revoke access for an existing member to a project. It does not explicitly name alternatives or exclusions, but the sibling list includes add_team_member and remove_team_member, and the description's focus on 'existing team member' and 'one authorized project' implies the distinction. A brief mention of when not to use it (e.g., for adding new members) would make it a 5.

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