sign-and-submit-transaction · Stellar MCP: Risk & Policy

WHAT IT DOES

What sign-and-submit-transaction does on Stellar

AI agents use sign-and-submit-transaction to create or update resources in Stellar — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Stellar environment.

WHY IT NEEDS A POLICY

Why sign-and-submit-transaction needs a policy

An AI agent can call sign-and-submit-transaction faster than any human can review — one bad instruction and it creates or modifies resources in Stellar by the hundred, each call as confident as the last.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

sign-and-submit-transaction Rate-limited

sign-and-submit-transaction 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": {
    "sign-and-submit-transaction": {
      "limits": [
        {
          "counter": "sign-and-submit-transaction_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 Stellar, so you can run agents against it safely.

FAQ

Questions about sign-and-submit-transaction

What does the sign-and-submit-transaction tool do? +

Sign and submit a Soroban transaction to the Stellar network. It is categorised as a Write tool in the Stellar MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on sign-and-submit-transaction? +

Register the Stellar MCP server in PolicyLayer and add a rule for sign-and-submit-transaction: 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 Stellar. Nothing to install.

What risk level is sign-and-submit-transaction? +

sign-and-submit-transaction is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit sign-and-submit-transaction? +

Yes. Add a rate_limit block to the sign-and-submit-transaction 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 sign-and-submit-transaction completely? +

Set action: deny in the PolicyLayer policy for sign-and-submit-transaction. 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 sign-and-submit-transaction? +

sign-and-submit-transaction is provided by the Stellar MCP server (stellar-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.