Build the final on-chain execTransaction UnsignedTx that lands a Safe (Gnosis Safe) multisig payload. The executor doesn't need to have pre-approved on-chain — when msg.sender is an owner, the Safe contract treats their inline (r=msg.sender, s=0, v=1) signature as implicit consent. So one of the ...
AI agents invoke prepare_safe_tx_execute to trigger actions in VaultPilot MCP. 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.
| Parameter | Type | Required | Description |
|---|---|---|---|
chain | string | — | |
executor | string | Yes | |
safeTxHash | string | Yes | |
safeAddress | string | Yes |
Parameters from the server's own tool schema.
prepare_safe_tx_execute triggers real processes with real consequences. An agent gone sideways doesn't fire it once — it starts dozens of builds, sends mass notifications, or burns through compute before anyone looks up.
Attacks that exploit this kind of access
Build the final on-chain execTransaction UnsignedTx that lands a Safe (Gnosis Safe) multisig payload. The executor doesn't need to have pre-approved on-chain — when msg.sender is an owner, the Safe contract treats their inline (r=msg.sender, s=0, v=1) signature as implicit consent. So one of the threshold "signatures" can be the executor themselves; the rest come from the on-chain approvedHashes registry filled by previous prepare_safe_tx_propose / prepare_safe_tx_approve calls. Refuses to build the tx when the threshold isn't met (which would just revert at execute time). Resolves the SafeTx body from the local store first, falling back to Safe Transaction Service. Returns an UnsignedTx the executor broadcasts via send_transaction — the OUTER tx sends 0 ETH (the inner value, if any, is paid by the Safe from its own balance during the inner CALL). It is categorised as a Execute tool in the VaultPilot MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
prepare_safe_tx_execute accepts 4 parameters: chain, executor, safeTxHash, safeAddress. Required: executor, safeTxHash, safeAddress. The full parameter table on this page comes from the server's own tool schema.
Register the VaultPilot MCP server in PolicyLayer and add a rule for prepare_safe_tx_execute: 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 VaultPilot MCP. Nothing to install.
prepare_safe_tx_execute is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the prepare_safe_tx_execute 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.
Set action: deny in the PolicyLayer policy for prepare_safe_tx_execute. 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.
prepare_safe_tx_execute is provided by the VaultPilot MCP server (vaultpilot-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.