prepare_marginfi_repay

SERVERVaultPilot MCP SOURCEvaultpilot-mcp

Critical RISK CLASS

Category Financial

Parameters 62 required

Recommended Approval-gatedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-github-szhygulin-vaultpilot-mcp/prepare-marginfi-repay.md

WHAT IT DOES

What prepare_marginfi_repay does on VaultPilot MCP

AI agents use prepare_marginfi_repay to commit financial operations through VaultPilot MCP, usually the final step of a payment, billing, or trading workflow. A call moves real money.

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 repay against outstanding debt in this bank.
`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).
`repayAll`	boolean	—	Set true to repay the full outstanding debt in this bank (SDK also clears the balance slot — cheaper for the user if they're closing out). Omit for partial.
`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.

RISK

Why prepare_marginfi_repay is rated Critical

This tool builds transactions that repay outstanding debt on MarginFi, a DeFi lending protocol. Repaying debt is a financial operation that moves crypto assets and alters on-chain financial positions. The 'repayAll' flag can clear entire debt positions, and BLIND-SIGN on Ledger indicates the transaction will be signed without full verification — significantly increasing misuse risk.

From the tool's definition 'REPAY tx against outstanding debt', 'repayAll: true to repay the full outstanding debt', 'BLIND-SIGN on Ledger', MarginFi DeFi lending protocol interaction

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs prepare_marginfi_repay safely

PolicyLayer is an MCP gateway: it sits between your AI agents and VaultPilot MCP, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For prepare_marginfi_repay, this is the rule to start with:

prepare_marginfi_repay Approval-gated

Any call to prepare_marginfi_repay is blocked until a human approves it. The rest of the server keeps working.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "prepare_marginfi_repay": {
      "deny_if": [
        {
          "conditions": [],
          "on_deny": "Requires human approval."
        }
      ]
    }
  }
}

GATE THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect VaultPilot MCP, apply this rule, and every prepare_marginfi_repay call is checked against it from then on.

FAQ

Questions about prepare_marginfi_repay

What does the prepare_marginfi_repay tool do? +

Build an unsigned MarginFi REPAY tx against outstanding debt in the named bank. Pass repayAll: true to repay the full outstanding debt (also clears the balance slot). DURABLE NONCE + prepare_marginfi_init prerequisites identical to prepare_marginfi_supply. BLIND-SIGN on Ledger. It is categorised as a Financial tool in the VaultPilot MCP MCP Server, which means it involves financial transactions. Block by default and require explicit approval.

What parameters does prepare_marginfi_repay accept? +

prepare_marginfi_repay accepts 6 parameters: mint, amount, symbol, wallet, repayAll, accountIndex. Required: amount, wallet. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on prepare_marginfi_repay? +

Register the VaultPilot MCP server in PolicyLayer and add a rule for prepare_marginfi_repay: 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.

What risk level is prepare_marginfi_repay? +

prepare_marginfi_repay is a Financial tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.

Can I rate-limit prepare_marginfi_repay? +

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

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

prepare_marginfi_repay 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.

KEEP EXPLORING

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