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

With no annotations, the description carries the full burden and delivers meaningful disclosure: 'takes effect immediately', the section disappearing from the target's room list, and reads/posts being refused. It omits idempotency and what happens when the identity has no existing grant, but the core effect is well conveyed.

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?

Two tight sentences with the permission constraint front-loaded and the consequence immediately after the action. Every clause earns its place.

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 two-required-parameter mutation with no output schema, the description covers the action, the actor restriction, and the observable effect. It leaves minor gaps around error cases and whether revocation is reversible, but nothing essential to correct invocation is missing.

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% for both parameters, so the description must compensate. 'Room' maps loosely to 'walled section' and 'identity's access grant' to identity_name, but formats, accepted values, or lookup semantics are not clarified beyond the self-descriptive parameter names.

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?

Specific verb (revoke) plus a precisely scoped resource (an identity's access grant to a walled section), which cleanly distinguishes it from the sibling hub_grant_access. An agent can select it correctly without opening the schema.

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?

States the actor restriction ('MODERATORS ONLY'), giving clear context for when the tool is appropriate. It does not explicitly name hub_grant_access as the inverse operation or state what to do when no grant exists, so it stops short of full when/when-not guidance.

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