set-before-send-hook · Osmosis MCP Server MCP: Risk & Policy

WHAT IT DOES

What set-before-send-hook does on Osmosis MCP Server

AI agents invoke set-before-send-hook to trigger actions in Osmosis MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why set-before-send-hook needs a policy

Setting a before-send hook configures executable code/logic that runs automatically on the blockchain for every subsequent token transfer. This is an Execute-category action because it triggers and installs external operation logic whose effects depend on the hook's code. It is high severity because a malicious or misconfigured hook could intercept, block, or manipulate all future token transfers for that asset.

From the tool's definition 'Set a before send hook for a token (admin only)' — installs/modifies an on-chain hook that executes custom logic before every token transfer

Risk signalsAdmin/system-level operation

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set-before-send-hook Rate-limited

set-before-send-hook stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "set-before-send-hook": {
      "limits": [
        {
          "counter": "set-before-send-hook_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about set-before-send-hook

What does the set-before-send-hook tool do? +

Set a before send hook for a token (admin only). It is categorised as a Execute tool in the Osmosis MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on set-before-send-hook? +

Register the Osmosis MCP Server MCP server in PolicyLayer and add a rule for set-before-send-hook: 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 Osmosis MCP Server. Nothing to install.

What risk level is set-before-send-hook? +

set-before-send-hook is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit set-before-send-hook? +

Yes. Add a rate_limit block to the set-before-send-hook 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 set-before-send-hook completely? +

Set action: deny in the PolicyLayer policy for set-before-send-hook. 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 set-before-send-hook? +

set-before-send-hook is provided by the Osmosis MCP Server MCP server (myronkoch-dev/mcp-osmosis). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.