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

readOnlyHint=false is consistent with a state-changing action, and the description adds real behavioral context beyond the annotation: the mine can only be exited from room 0. It does not say where the player ends up, whether the action can fail otherwise, or whether it costs anything.

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?

One short sentence with the primary action stated first and the exceptional constraint in parentheses. No redundant wording.

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 zero-parameter state-changing tool with no output schema, the description covers the action and its one known special case. Minor gaps remain: the resulting location after exit and any failure conditions are unspecified.

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 tool takes zero parameters, so there is nothing for the description to disambiguate. Baseline 4 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 gives a specific verb+resource: leave the building to the street. That is clearly distinct from the inverse sibling game_enter_building, even though the sibling is not named explicitly.

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?

Usage is implied — call it when you are inside a building and want to be outside — and the parenthetical adds one concrete condition (from the mine, only from room 0). There is no explicit statement of when not to use it or which sibling to use instead (e.g., game_move for movement indoors).

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