End an iOS Live Activity.
AI agents use end_live_activity to create or update resources in OneSignal MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your OneSignal MCP Server environment.
An AI agent can call end_live_activity faster than any human can review — one bad instruction and it creates or modifies resources in OneSignal MCP Server by the hundred, each call as confident as the last.
Attacks that exploit this kind of access
End an iOS Live Activity. It is categorised as a Write tool in the OneSignal MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the OneSignal MCP Server MCP server in PolicyLayer and add a rule for end_live_activity: 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 OneSignal MCP Server. Nothing to install.
end_live_activity 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 end_live_activity 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 end_live_activity. 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.
end_live_activity is provided by the OneSignal MCP Server MCP server (weirdbrains/onesignal-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.