prepare_marginfi_supply

SERVERVaultPilot MCP SOURCEvaultpilot-mcp

Critical RISK CLASS

Category Financial

Parameters 52 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-supply.md

WHAT IT DOES

What prepare_marginfi_supply does on VaultPilot MCP

AI agents use prepare_marginfi_supply 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`	string	—	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 supply (e.g. "1.5" for 1.5 USDC). Decimals resolved from the bank's mint — do NOT pass raw base units.
`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	Solana wallet executing the supply. Must have an initialized MarginfiAccount (run prepare_marginfi_init first) AND a durable-nonce account (prepare_solana_nonce
`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_supply is rated Critical

This tool builds a transaction that supplies crypto assets into a DeFi lending protocol (MarginFi), constituting a financial commitment of user funds. While it builds an 'unsigned' transaction, it is the direct precursor to moving assets into a yield-bearing position.

From the tool's definition 'Supplies the specified amount of the underlying token into the user's MarginfiAccount position in that bank, earning the bank's supply APY' — commits DeFi lending/supply position; 'BLIND-SIGN on Ledger' — signs financial transaction; MarginFi is a DeFi…

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs prepare_marginfi_supply 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_supply, this is the rule to start with:

prepare_marginfi_supply Approval-gated

Any call to prepare_marginfi_supply 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_supply": {
      "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_supply call is checked against it from then on.

FAQ

Questions about prepare_marginfi_supply

What does the prepare_marginfi_supply tool do? +

Build an unsigned MarginFi SUPPLY tx for a given bank (by symbol or mint). Supplies the specified amount of the underlying token into the user's MarginfiAccount position in that bank, earning the bank's supply APY. DURABLE NONCE REQUIRED + prepare_marginfi_init must have run first; otherwise this tool errors. Pre-flight: bank-pause check; invalid-mint check (MarginFi only lists a subset of SPL tokens). Uses v0 VersionedTransaction + MarginFi group ALTs for compact wire size. BLIND-SIGN on Ledger — match the Message Hash on-device after preview_solana_send. 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_supply accept? +

prepare_marginfi_supply 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.

How do I enforce a policy on prepare_marginfi_supply? +

Register the VaultPilot MCP server in PolicyLayer and add a rule for prepare_marginfi_supply: 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_supply? +

prepare_marginfi_supply 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_supply? +

Yes. Add a rate_limit block to the prepare_marginfi_supply 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_supply completely? +

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

prepare_marginfi_supply 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.

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