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

The description discloses important side effects beyond the annotations: every created room is listed in defaultRooms, pinned=true only affects new users (existing users are not added), and the response includes the new room object with its JID. It also lists concrete auth and error conditions, which is substantial behavioral context.

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 dense but well-organized: core action first, then side effects, return value, auth, and errors. Every sentence earns its place and there is no filler.

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 create tool with no output schema, the description covers prerequisites, side effects, return shape, and error codes. An agent has enough information to invoke it safely and understand the result.

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 100%, so the baseline is 3, but the description adds meaningful parameter nuance: pinned=true does not add existing users, and rooms are placed in the app's defaultRooms. This goes slightly beyond the schema descriptions.

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 begins with a specific verb and resource: 'Create a new chat room (MUC room) inside an app the caller owns.' This clearly distinguishes the tool from siblings like ethora-app-delete-chat and chat-message tools.

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?

It gives clear context for when the tool is appropriate: the caller must own the app and have an active user-auth session. It explains pinned vs. non-pinned behavior for auto-join, though it does not explicitly name alternatives or when-not-to-use conditions.

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