Prototype: add a reaction (interaction) to a node. A reaction pairs a trigger with an action. Existing reactions are preserved.\n\nTrigger types: ON_CLICK, ON_HOVER, ON_PRESS, ON_DRAG, ON_MEDIA_END, AFTER_TIMEOUT, MOUSE_UP, MOUSE_DOWN, MOUSE_ENTER, MOUSE_LEAVE, ON_KEY_DOWN, ON_MEDIA_HIT.\n\nActio...
AI agents use figma_add_reaction to create or update resources in Figma MCP Bridge — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Figma MCP Bridge environment.
This tool creates or modifies interactive prototype behaviors in Figma documents. It is reversible (reactions can be removed or changed), does not execute arbitrary code or external operations, does not delete data, and does not involve financial transactions. It is a Write operation because it modifies document state.
From the tool's definition Tool description states it will 'add a reaction (interaction) to a node' and 'Existing reactions are preserved', indicating reversible modification of Figma document state. The tool creates or modifies interactive prototypes by pairing triggers with actions.
Documented attack patterns abuse exactly the kind of access figma_add_reaction gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Figma MCP Bridge, and nothing reaches the server without passing your rules. This is the rule we recommend for figma_add_reaction:
{
"version": "1",
"default": "deny",
"tools": {
"figma_add_reaction": {
"limits": [
{
"counter": "figma_add_reaction_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}figma_add_reaction 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.
Free to start. No card required.
Prototype: add a reaction (interaction) to a node. A reaction pairs a trigger with an action. Existing reactions are preserved.\n\nTrigger types: ON_CLICK, ON_HOVER, ON_PRESS, ON_DRAG, ON_MEDIA_END, AFTER_TIMEOUT, MOUSE_UP, MOUSE_DOWN, MOUSE_ENTER, MOUSE_LEAVE, ON_KEY_DOWN, ON_MEDIA_HIT.\n\nAction types: NODE (navigate/overlay/scroll — set navigation field), BACK, CLOSE, URL.\n\nFor NODE actions, navigation values: NAVIGATE (go to frame), SWAP (replace current frame), OVERLAY (open as overlay), SCROLL_TO (scroll to frame), CHANGE_TO (change component variant). It is categorised as a Write tool in the Figma MCP Bridge MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Figma MCP Bridge MCP server in PolicyLayer and add a rule for figma_add_reaction: 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 Figma MCP Bridge. Nothing to install.
figma_add_reaction 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 figma_add_reaction 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 figma_add_reaction. 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.
figma_add_reaction is provided by the Figma MCP Bridge MCP server (magic-spells/figma-mcp-bridge). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Figma MCP Bridge, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
88 Figma MCP Bridge tools catalogued and risk-classified — across an index of 43,000+ MCP servers.