mp_add_spawner
Add a MultiplayerSpawner node under a parent (undoable). Godot 4 high-level multiplayer replicates server-spawned nodes to clients: set spawn_path to the node whose children are auto-replicated, and register the scenes it may spawn. Pure node authoring — no service is started.
This record as markdown: /tools/breakpoint-mcp/mp-add-spawner.md
What mp_add_spawner does on Breakpoint
AI agents use mp_add_spawner to create or update resources in Breakpoint, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Breakpoint environment.
| Parameter | Type | Required | Description |
|---|---|---|---|
name | string | — | Node name (default MultiplayerSpawner) A taken name gets a number appended (`SFX`->`SFX2`), reported as `coerced` + `requested`. |
spawn_path | string | — | NodePath (relative to the spawner) whose children are auto-replicated |
parent_path | string | Yes | Parent node path relative to the scene root; "." for the root |
spawnable_scenes | array | — | res:// scenes the spawner may instantiate (add_spawnable_scene) |
Parameters from the server's own tool schema.
Why mp_add_spawner is rated Medium
An AI agent can call mp_add_spawner faster than any human can review: one bad instruction and it creates or modifies resources in Breakpoint by the hundred, each call as confident as the last.
Attacks that exploit this kind of access
The rule that runs mp_add_spawner safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Breakpoint, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For mp_add_spawner, this is the rule to start with:
mp_add_spawner stays usable, but capped: an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Breakpoint, apply this rule, and every mp_add_spawner call is checked against it from then on.
Questions about mp_add_spawner
Add a MultiplayerSpawner node under a parent (undoable). Godot 4 high-level multiplayer replicates server-spawned nodes to clients: set spawn_path to the node whose children are auto-replicated, and register the scenes it may spawn. Pure node authoring — no service is started. It is categorised as a Write tool in the Breakpoint MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
mp_add_spawner accepts 4 parameters: name, spawn_path, parent_path, spawnable_scenes. Required: parent_path. The full parameter table on this page comes from the server's own tool schema.
Register the Breakpoint MCP server in PolicyLayer and add a rule for mp_add_spawner: 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 Breakpoint. Nothing to install.
mp_add_spawner 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 mp_add_spawner 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 mp_add_spawner. 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.
mp_add_spawner is provided by the Breakpoint MCP server (breakpoint-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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