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

Annotations already flag this as a destructive, non-read-only, non-idempotent, open-world mutation. The description adds value beyond them: the operation toggles membership rather than appending, permission derives from room role not workspace role, and encrypted rooms require a different execution path. It does not disclose what happens to the member's existing content or whether the call is reversible.

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 tight sentences, front-loaded with the action and its scope, then the two conditional permission regimes. No filler and nothing repeated from the schema.

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 4-parameter destructive mutation with no output schema, the description supplies the essential prerequisites (role-based permission, encryption runtime, credential handling implied by the schema). Return behavior is absent, but with no output schema that is a minor gap.

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 75%, so most parameters are already documented in the schema, including the sensitive 'connection' credential. The description implies the boolean toggle via 'add or remove' but adds no format or constraint detail beyond what the schema provides, so the baseline 3 applies.

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 pair ('add or remove') and a precise resource ('an existing workspace agent in one room only'), which cleanly separates it from list-style siblings like room_members and workspace-level tools. It does not name a sibling alternative explicitly, so it stops 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?

Gives concrete eligibility rules: room creator or account owner with room access for standard rooms, and the creator's local encryption runtime for encrypted rooms, plus an explicit exclusion ('never infer permission from workspace membership'). Clear context and an exclusion, though it doesn't route to a sibling tool when the caller lacks permission.

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