# piece_move

Move a piece onto a board cell by id (reparent + snap via board_place), optionally with a short scale "pop" animation authored from Group C anim primitives. Undoable node authoring; purely additive — it emits only existing node / anim ops, never a new engine call. Returns the piece's new path.

Agent View of the PolicyLayer registry record for `piece_move`. HTML page: https://policylayer.com/tools/breakpoint-mcp/piece-move

## Facts

- Tool: `piece_move`
- Server: Breakpoint (`breakpoint-mcp`) — https://policylayer.com/tools/breakpoint-mcp.md
- Install: `npx -y breakpoint-mcp`
- Homepage: https://www.npmjs.com/package/breakpoint-mcp
- Risk category: Write (Medium risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 6 (3 required)
- Recommended policy verdict: Rate-limited

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `to` | string | yes | Destination cell id (resolves to <board>/cell_<to>) |
| `from` | string | no | Source cell id, echoed in the result for the caller's convenience |
| `node` | string | yes | Node path of the piece to move |
| `align` | object | no | Offset from the cell origin in px (default 0,0 — centred on the anchor) |
| `board` | string | yes | Board root node path in the open scene ("." if the board is the scene root) |
| `animate` | object | no | Optional pop animation; omitted → an instant snap |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "piece_move",
    "arguments": {
      "to": "<to>",
      "node": "<node>",
      "board": "<board>"
    }
  }
}
```

## Why piece_move is rated Medium

This tool creates or modifies data (piece position on board) reversibly through reparenting and animation operations. The 'Undoable' nature confirms it is Write (not Destructive). While it triggers animation operations from the sibling anim tools, the core function is state modification rather than arbitrary code execution.

From the tool's own definition: "Tool description states it performs 'Move a piece onto a board cell' and 'reparent + snap via board_place', which modifies the state of board pieces. Described as 'Undoable node authoring; purely additive' indicating reversible modifications to game state."

Risk signals: High parameter count (13 properties)

## Use case

AI agents use piece_move 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.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Breakpoint:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "piece_move": {
      "limits": [
        {
          "counter": "piece_move_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Breakpoint (273)

- `anim_delete` — Destructive — https://policylayer.com/tools/breakpoint-mcp/anim-delete.md
- `anim_remove_key` — Destructive — https://policylayer.com/tools/breakpoint-mcp/anim-remove-key.md
- `filesystem_move` — Destructive — https://policylayer.com/tools/breakpoint-mcp/filesystem-move.md
- `gd_rename` — Destructive — https://policylayer.com/tools/breakpoint-mcp/gd-rename.md
- `inputmap_erase_action` — Destructive — https://policylayer.com/tools/breakpoint-mcp/inputmap-erase-action.md
- `mp_wire_rpc` — Destructive — https://policylayer.com/tools/breakpoint-mcp/mp-wire-rpc.md
- `node_delete` — Destructive — https://policylayer.com/tools/breakpoint-mcp/node-delete.md
- `project_remove_autoload` — Destructive — https://policylayer.com/tools/breakpoint-mcp/project-remove-autoload.md
- `resource_save` — Destructive — https://policylayer.com/tools/breakpoint-mcp/resource-save.md
- `resource_set_import_settings` — Destructive — https://policylayer.com/tools/breakpoint-mcp/resource-set-import-settings.md
- `runtime_node_remove` — Destructive — https://policylayer.com/tools/breakpoint-mcp/runtime-node-remove.md
- `runtime_peer_stop` — Destructive — https://policylayer.com/tools/breakpoint-mcp/runtime-peer-stop.md
- `scene_close` — Destructive — https://policylayer.com/tools/breakpoint-mcp/scene-close.md
- `scene_reload` — Destructive — https://policylayer.com/tools/breakpoint-mcp/scene-reload.md
- `shader_set_code` — Destructive — https://policylayer.com/tools/breakpoint-mcp/shader-set-code.md
- `tilemap_clear` — Destructive — https://policylayer.com/tools/breakpoint-mcp/tilemap-clear.md
- `vcs_restore` — Destructive — https://policylayer.com/tools/breakpoint-mcp/vcs-restore.md
- `vcs_stash` — Destructive — https://policylayer.com/tools/breakpoint-mcp/vcs-stash.md
- `cs_dbg_attach` — Execute — https://policylayer.com/tools/breakpoint-mcp/cs-dbg-attach.md
- `cs_dbg_continue` — Execute — https://policylayer.com/tools/breakpoint-mcp/cs-dbg-continue.md
- `cs_dbg_launch` — Execute — https://policylayer.com/tools/breakpoint-mcp/cs-dbg-launch.md
- `cs_dbg_restart` — Execute — https://policylayer.com/tools/breakpoint-mcp/cs-dbg-restart.md
- `cs_dbg_set_breakpoints` — Execute — https://policylayer.com/tools/breakpoint-mcp/cs-dbg-set-breakpoints.md
- `cs_dbg_set_exception_breakpoints` — Execute — https://policylayer.com/tools/breakpoint-mcp/cs-dbg-set-exception-breakpoints.md
- `cs_dbg_set_variable` — Execute — https://policylayer.com/tools/breakpoint-mcp/cs-dbg-set-variable.md
- `cs_dbg_step` — Execute — https://policylayer.com/tools/breakpoint-mcp/cs-dbg-step.md
- `dbg_attach` — Execute — https://policylayer.com/tools/breakpoint-mcp/dbg-attach.md
- `dbg_continue` — Execute — https://policylayer.com/tools/breakpoint-mcp/dbg-continue.md
- `dbg_data_breakpoints` — Execute — https://policylayer.com/tools/breakpoint-mcp/dbg-data-breakpoints.md
- `dbg_goto` — Execute — https://policylayer.com/tools/breakpoint-mcp/dbg-goto.md
- …and 243 more: https://policylayer.com/tools/breakpoint-mcp.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=breakpoint-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/breakpoint-mcp