# prepare_uniswap_swap Prepare a direct Uniswap V3 swap (bypasses LiFi aggregator). Use this ONLY when the user explicitly asks for Uniswap — otherwise default to prepare_swap which compares routes across venues. Same-chain only (Uniswap V3 is not a bridge). Auto-picks the best pool fee tier (100/500/3000/10000 bps) by quoting all four against QuoterV2 and choosing the one with the best price; pass feeTier to override. Supports ERC-20 <-> ERC-20, native-in (ETH -> ERC-20), and native-out (ERC-20 -> ETH). Both exact-in and exact-out. Returns an unsigned tx (with a reset+approve chain when the router needs allowance) that send_transaction can forward to Ledger Live. Single-hop only in v1 — multi-hop routes through an intermediate asset (e.g. via WETH) fall back to prepare_swap. Agent View of the PolicyLayer registry record for `prepare_uniswap_swap`. HTML page: https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-uniswap-swap ## Facts - Tool: `prepare_uniswap_swap` - Server: VaultPilot MCP (`vaultpilot-mcp`) — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp.md - Install: `npx -y vaultpilot-mcp` - Homepage: https://github.com/szhygulin/vaultpilot-mcp - Risk category: Financial (Critical risk) - Registry record: grade F, identity unverified - Server rate-limited: no - Parameters: 11 (5 required) - Recommended policy verdict: Approval-gated ## Parameters | Parameter | Type | Required | Description | | --- | --- | --- | --- | | `chain` | string | yes | | | `amount` | string | yes | Human-readable decimal amount, NOT raw wei/base units. Example: "1.5" for 1.5 USDC, "0.01" for 0.01 ETH. Interpreted as fromToken input by default; set `amountS | | `wallet` | string | yes | | | `feeTier` | number | no | Optional fee-tier override (100 / 500 / 3000 / 10000 bps). When omitted, QuoterV2 is queried across all four tiers and the best-pricing pool is picked. | | `toToken` | object | yes | | | `fromToken` | object | yes | | | `amountSide` | string | no | Which side of the swap `amount` refers to. "from" (default) = exact-in: spend exactly `amount` of fromToken, receive a variable output. "to" = exact-out: receiv | | `slippageBps` | integer | no | Slippage tolerance in basis points (50 = 0.5%). Default 50. Hard-capped at 500 (5%); > 100 requires `acknowledgeHighSlippage: true` to prevent MEV sandwiching. | | `toTokenDecimals` | integer | no | Optional decimals hint for toToken if on-chain lookup fails. Native is 18. | | `fromTokenDecimals` | integer | no | Optional decimals hint for fromToken if on-chain lookup fails. Native is 18. | | `acknowledgeHighSlippage` | boolean | no | Opt-in flag required when slippageBps > 100. Forces explicit acknowledgement of unusually-high slippage. | Parameters from the server's own tool schema. ## Example call (MCP tools/call, JSON-RPC 2.0) ```json { "jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": { "name": "prepare_uniswap_swap", "arguments": { "chain": "", "amount": "", "wallet": "", "toToken": {}, "fromToken": {} } } } ``` ## Why prepare_uniswap_swap is rated Critical This tool prepares a cryptocurrency swap transaction on Uniswap V3, which is a DeFi financial operation involving the exchange of crypto assets. Even though it returns an unsigned transaction (not yet executed), it constructs the financial transaction payload including token approvals and swap parameters. This falls squarely in the Financial category as it commits to a specific financial trade with real asset value. From the tool's own definition: "prepare a direct Uniswap V3 swap...ERC-20 <-> ERC-20, native-in (ETH -> ERC-20), and native-out (ERC-20 -> ETH). Both exact-in and exact-out. Returns an unsigned tx (with a reset+approve chain when the router needs allowan" Risk signals: High parameter count (11 properties) ## Use case AI agents use prepare_uniswap_swap to commit financial operations through VaultPilot MCP, usually the final step of a payment, billing, or trading workflow. A call moves real money. ## Recommended policy (PolicyLayer) Verdict: **Approval-gated**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches VaultPilot MCP: ```json { "version": "1", "default": "deny", "tools": { "prepare_uniswap_swap": { "deny_if": [ { "conditions": [], "on_deny": "Requires human approval." } ] } } } ``` ## Other tools on VaultPilot MCP (188) - `prepare_btc_lifi_swap` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-btc-lifi-swap.md - `prepare_btc_rbf_bump` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-btc-rbf-bump.md - `prepare_jito_stake` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-jito-stake.md - `prepare_marginfi_init` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-marginfi-init.md - `prepare_solana_nonce_close` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-solana-nonce-close.md - `prepare_sunswap_swap` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-sunswap-swap.md - `prepare_uniswap_v3_burn` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-uniswap-v3-burn.md - `prepare_uniswap_v3_mint` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-uniswap-v3-mint.md - `remove_contact` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/remove-contact.md - `unregister_btc_multisig_wallet` — Destructive — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/unregister-btc-multisig-wallet.md - `combine_btc_psbts` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/combine-btc-psbts.md - `pair_ledger_btc` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/pair-ledger-btc.md - `prepare_aave_repay` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-aave-repay.md - `prepare_btc_multisig_send` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-btc-multisig-send.md - `prepare_compound_repay` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-compound-repay.md - `prepare_compound_supply` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-compound-supply.md - `prepare_curve_swap` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-curve-swap.md - `prepare_custom_call` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-custom-call.md - `prepare_kamino_init_user` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-kamino-init-user.md - `prepare_kamino_supply` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-kamino-supply.md - `prepare_lido_unstake` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-lido-unstake.md - `prepare_lido_unwrap` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-lido-unwrap.md - `prepare_lido_wrap` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-lido-wrap.md - `prepare_native_stake_deactivate` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-native-stake-deactivate.md - `prepare_native_stake_delegate` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-native-stake-delegate.md - `prepare_rocketpool_unstake` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-rocketpool-unstake.md - `prepare_safe_tx_execute` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-safe-tx-execute.md - `prepare_solana_lifi_swap` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-solana-lifi-swap.md - `prepare_solana_nonce_init` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-solana-nonce-init.md - `prepare_solana_swap` — Execute — https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp/prepare-solana-swap.md - …and 158 more: https://policylayer.com/tools/io-github-szhygulin-vaultpilot-mcp.md ## For agents This record is a snapshot. Live verdicts and the full registry: - Check every server in your MCP config at once: `npx -y policylayer stack` - Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md) - Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events` --- Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-github-szhygulin-vaultpilot-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-szhygulin-vaultpilot-mcp