receive_handoff · Engram MCP: Risk & Policy

WHAT IT DOES

What receive_handoff does on Engram

AI agents use receive_handoff to create or update resources in Engram — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Engram environment.

WHY IT NEEDS A POLICY

Why receive_handoff needs a policy

This tool writes/injects a context blob received from another agent into the system's memory or state. It creates or modifies data (memory/context) reversibly, but does not delete or execute arbitrary code. The 'injection' language implies writing new data into the epistemic engine.

From the tool's definition 'Receive a context blob from another agent and confirm injection'

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

receive_handoff Rate-limited

receive_handoff 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "receive_handoff": {
      "limits": [
        {
          "counter": "receive_handoff_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Engram, so you can run agents against it safely.

FAQ

Questions about receive_handoff

What does the receive_handoff tool do? +

Receive a context blob from another agent and confirm injection. It is categorised as a Write tool in the Engram MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on receive_handoff? +

Register the Engram MCP server in PolicyLayer and add a rule for receive_handoff: 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 Engram. Nothing to install.

What risk level is receive_handoff? +

receive_handoff is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit receive_handoff? +

Yes. Add a rate_limit block to the receive_handoff 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.

How do I block receive_handoff completely? +

Set action: deny in the PolicyLayer policy for receive_handoff. 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.

What MCP server provides receive_handoff? +

receive_handoff is provided by the Engram MCP server (tinydarkforge/engram). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.