Build an unsigned MarginFi BORROW tx against the user's supplied collateral. Pre-flight refuses if the account has zero free collateral. The SDK computes the required oracle-refresh instructions and the health-factor gate is enforced on-chain — but this tool is the right place to surface a clear ...
AI agents call prepare_marginfi_borrow to permanently remove resources in VaultPilot MCP — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
| Parameter | Type | Required | Description |
|---|---|---|---|
mint | object | — | Base58 SPL mint address. Used as an override or when the token isn't in the canonical SOLANA_TOKENS table. Exactly one of `symbol` or `mint` must be passed. |
amount | string | Yes | Human-readable decimal amount to borrow. Pre-flight refuses if the account has zero free collateral. |
symbol | string | — | Canonical token symbol (USDC, SOL, USDT, JUP, BONK, JTO, mSOL, jitoSOL). The builder resolves this to the underlying mint; MarginFi treats SOL as wSOL internall |
wallet | string | Yes | Base58 Solana mainnet address (ed25519 pubkey, 43 or 44 chars). |
accountIndex | integer | — | MarginfiAccount slot (0 = first, 1 = second, ...). Most users stay on 0. Use a different index to segregate positions across multiple MarginfiAccounts owned by |
Parameters from the server's own tool schema.
An AI agent that decides to call prepare_marginfi_borrow doesn't hesitate, doesn't double-check, and doesn't stop at one. Whatever it removes from VaultPilot MCP is gone — there is no undo for destructive operations.
Attacks that exploit this kind of access
Build an unsigned MarginFi BORROW tx against the user's supplied collateral. Pre-flight refuses if the account has zero free collateral. The SDK computes the required oracle-refresh instructions and the health-factor gate is enforced on-chain — but this tool is the right place to surface a clear error rather than burning SOL on a reverting tx. DURABLE NONCE + prepare_marginfi_init prerequisites identical to prepare_marginfi_supply. BLIND-SIGN on Ledger. It is categorised as a Destructive tool in the VaultPilot MCP MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
prepare_marginfi_borrow accepts 5 parameters: mint, amount, symbol, wallet, accountIndex. Required: amount, wallet. 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_marginfi_borrow: 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_marginfi_borrow is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the prepare_marginfi_borrow 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_marginfi_borrow. 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_marginfi_borrow 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.