memory_episode_end · MCP Router MCP: Risk & Policy

WHAT IT DOES

What memory_episode_end does on MCP Router

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

WHY IT NEEDS A POLICY

Why memory_episode_end needs a policy

Ending an episode triggers the generation and storage of a summary along with entity/topic extraction — this modifies/creates persisted data (the episode summary and extracted entities). It is reversible in principle (the episode record could be deleted), so Write is more appropriate than Destructive.

From the tool's definition End the current episode. This generates a summary and extracts key entities and topics.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

memory_episode_end Rate-limited

memory_episode_end 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": {
    "memory_episode_end": {
      "limits": [
        {
          "counter": "memory_episode_end_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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

FAQ

Questions about memory_episode_end

What does the memory_episode_end tool do? +

End the current episode. This generates a summary and extracts key entities and topics. It is categorised as a Write tool in the MCP Router MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on memory_episode_end? +

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

What risk level is memory_episode_end? +

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

Can I rate-limit memory_episode_end? +

Yes. Add a rate_limit block to the memory_episode_end 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 memory_episode_end completely? +

Set action: deny in the PolicyLayer policy for memory_episode_end. 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 memory_episode_end? +

memory_episode_end is provided by the MCP Router MCP server (justinpreston/mcp-router). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.