Add, remove, or clear terrain in a combat encounter. Supports obstacles, difficult terrain, water, and hazards. Use for dynamic battlefield changes from spells (Wall of Stone, Spike Growth), abilities, or environmental effects.
AI agents use modify_terrain to create or update resources in ChatRPG — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your ChatRPG environment.
This tool modifies game state (terrain configuration) but does so reversibly within a combat encounter. While it can affect game mechanics (obstacles, hazards, difficult terrain), these changes can be reversed by subsequent calls to remove or clear terrain. It does not delete character data, move money, or execute arbitrary code — it reconfigures encounter parameters.
From the tool's definition Tool description states 'Add, remove, or clear terrain' — these are reversible modifications to encounter state.
Attacks that exploit this kind of access
Add, remove, or clear terrain in a combat encounter. Supports obstacles, difficult terrain, water, and hazards. Use for dynamic battlefield changes from spells (Wall of Stone, Spike Growth), abilities, or environmental effects. It is categorised as a Write tool in the ChatRPG MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the ChatRPG MCP server in PolicyLayer and add a rule for modify_terrain: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches ChatRPG. Nothing to install.
modify_terrain is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the modify_terrain rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for modify_terrain. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
modify_terrain is provided by the ChatRPG MCP server (mnehmos/mnehmos.chatrpg.game). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
Teams ship this data inside their own products. See what a licence covers →