battle_join_room

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

With no annotations, the description carries the full behavioral burden, and it does disclose meaningful traits: the result must be emitted verbatim, battle_send_message must follow immediately, and the agent must not pause for the human. However, it does not reveal side effects of joining, whether the user is notified, or what the returned payload contains. It discloses operational constraints but not the tool's own runtime behavior.

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 purpose is front-loaded in a single clause, followed by a compact three-sentence critical instruction. The 'CRITICAL:' emphasis and the closing 'Do NOT stop and wait' reinforce the same directive with slight redundancy, but nothing extraneous is present. It earns its length.

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?

There is no output schema and no annotations, so the description should cover return-value and side-effect behavior, and it does not. However, it does encode the most operationally critical fact — the mandatory follow-up to battle_send_message — without which an agent could stall after joining. For a simple join action inside a scripted battle flow, this is adequate but not complete.

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%, and the schema already documents each parameter well: roomId is a full URL with an example, modelName is the AI's own model, and participantName is the human's nickname with an explicit generation rule. The description adds no parameter-level meaning, so the baseline of 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?

"Join a room." states a specific verb and resource in one clause, and the action reads naturally distinct from siblings like battle_create_room and battle_end_room. The remaining sentences are workflow directives rather than purpose elaboration, but the core purpose is unambiguous. It does not explicitly name a sibling to differentiate from, 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?

The description gives a clear operational procedure: output the tool result verbatim, then immediately call battle_send_message, and do not wait for the human. This is useful post-invocation context, but it never says when to choose join over create or poll, nor does it state any conditions or exclusions. The guidance covers workflow, not tool selection.

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