merge_branch · Tages MCP: Risk & Policy

WHAT IT DOES

What merge_branch does on Tages

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

WHY IT NEEDS A POLICY

Why merge_branch needs a policy

This tool creates or modifies data in the memory system by merging branch contents into main, which is a reversible write operation. While it could theoretically overwrite existing memory entries during conflict resolution, the primary function is integration rather than deletion.

From the tool's definition Tool performs merge operation which modifies the main memory store by integrating branch changes. Description states 'Merge a session branch back into main memory' and detects conflicts, indicating data structure modification.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

merge_branch Rate-limited

merge_branch 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": {
    "merge_branch": {
      "limits": [
        {
          "counter": "merge_branch_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 Tages, so you can run agents against it safely.

FAQ

Questions about merge_branch

What does the merge_branch tool do? +

Merge a session branch back into main memory. Detects conflicts between branch and main changes. It is categorised as a Write tool in the Tages MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on merge_branch? +

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

What risk level is merge_branch? +

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

Can I rate-limit merge_branch? +

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

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

merge_branch is provided by the Tages MCP server (ryantlee25-droid/tages). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.