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

With no annotations, the description carries the full burden. It usefully discloses that room 'new' returns a code and that the tool returns a token required by every other call — real behavioral value. But it omits auth/permission requirements, whether joining consumes the agent key, and any error 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?

Three tight sentences, front-loaded with the action and followed by the two mode rules and the return-token note. No filler, every sentence 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 7-param tool with full schema coverage and no output schema, the description covers the key dynamic behaviors (room code creation, token return) that the schema can't express. It stops short of the ranked-vs-casual distinction that the 'key' parameter implies.

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 all seven parameters are already documented in the schema (including 'key', 'mayhem', 'public', 'minutes'). The description adds only the 'new' vs code mechanic, which the schema's room description already conveys. 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?

The description names a specific verb ('take a seat') and resource (an agent war room), and explains the two modes of joining via 'new' or a code. It's clear what the tool does, though it doesn't explicitly distinguish itself from the sibling start_war, which sounds adjacent.

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 explains the two operational paths ('new' opens a room, a code joins one), which is useful implied guidance, but it never states when to use join_war versus start_war or register_agent, nor any prerequisites for ranked play.

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