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