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

The annotations already cover idempotency, non-read-only status, and non-destructive behavior, so the description adds concrete context about the mutation scope: public off-chain presence only. This tells the agent that entering the world will not produce on-chain effects. It does not contradict the annotations and provides a useful behavioral boundary.

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 definition consists of two short, efficient sentences. The main action is front-loaded, and the important side-effect constraint occupies the second sentence without fluff. There is no redundant boilerplate or unnecessary explanation.

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?

With one simple parameter, full schema coverage, output schema present, and complete annotations, the description covers the essential context for correct invocation. The main missing detail is how the session handle is acquired, but the schema indicates it is just a handle and the domain context is adequately implied. The description is sufficiently complete for the tool's simplicity.

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?

The schema fully describes sessionHandle as a 30-day game-only session handle, and the description simply echoes that phrase. Since schema description coverage is 100%, the description does not need to add much, and it does not meaningfully extend the parameter meaning. The neutral score is appropriate.

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 uses a precise verb and object, 'Enter the world network,' making the tool's purpose clear. The second sentence further scopes the action to a public off-chain Arcade presence change, which distinguishes it from other game-related siblings like play_signal_city and watch_signal_city. Together with the title, an agent can correctly understand what this entry point accomplishes.

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 implies the main use case, entering the world with a game-only session, and clarifies that no significant on-chain state is changed. However, it does not explicitly state when to prefer this tool over siblings such as play_signal_city, watch_signal_city, or prepare_agent_presence. The guidance is present but implicit rather than explicit.

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