MCPBuddy

An account-scoped MCP connection hub for Claude, OpenAI and Grok, designed for Vercel.

中文产品介绍与规划请见 docs/product-overview.zh-CN.md。

Product model

1. Sign in with GitHub or Google.
2. Create a private MCP endpoint at /api/mcp (or a custom subdomain at the edge).
3. Connect that endpoint from Claude, ChatGPT, or Grok.
4. Bind an optional Solana wallet with a signed challenge.
5. Publish pages or upload content through MCP tools.

Vercel setup

Create GitHub and Google OAuth clients, then add the variables in .env.example. The production callback URLs are https://mcpbuddy.creatorsand.fun/api/auth/callback/github and https://mcpbuddy.creatorsand.fun/api/auth/callback/google. Connect both Vercel Postgres and a private Vercel Blob store. Run npm run build before deploying.

Run drizzle/0000_initial.sql once against Vercel Postgres. The unique (kind, jti) constraint gives authorization-code and refresh-token rotation an atomic replay barrier across serverless invocations. Blob is used for publishable file payloads.

publish_html(html) accepts one complete HTML document (up to 1 MB) and returns a direct Vercel Blob public URL with text/html content type. The URL is publicly accessible and the document is deliberately served from the isolated Blob origin rather than the MCPBuddy app origin. Do not publish secrets, private data, or reusable credentials.

get_solana_asset_balances reads the bound wallet's configured famous-token list plus tokens in the current account's wallet whitelist, returning a USD quote where available. The included list covers SOL, USDC, USDT, wSOL, JUP, JTO, PYTH, RAY, ORCA, W, WIF, and BONK, grouped by categories such as Native, Stablecoin, DeFi, Infrastructure, Staking, Wrapped, and Meme. Whitelisted tokens are account-scoped, are included only when their balance is nonzero, and may have no USD quote. When CoinGecko has no quote, MCPBuddy requests a read-only Jupiter route quote for exactly one token into USDC (for example, 1 SPACEX → 90.14 USDC); it neither creates nor signs a transaction. list_solana_swap_tokens also includes a current-account whitelist token when Jupiter can quote it; its on-chain/Jupiter decimal metadata is resolved before it can be used by the symbol-based swap or transfer tools, and configured tokens include category and tags metadata for client grouping. Edit config/solana-famous-tokens.json to choose the queried assets; each item requires symbol, name, mint (use null for SOL), decimals, and coingeckoId, with optional category and tags. Set SOLANA_RPC_URL to a production RPC provider endpoint to avoid public-RPC rate limits; when omitted, it uses Solana's public mainnet endpoint. Prices are fetched from CoinGecko and are indicative only.

Solana swaps

MCP tool packages

MCP tool registration is organized as packages under lib/mcp/plugins/. The solana/base package contains bound-wallet, portfolio, unsigned SPL transfer, transaction-status, and MCP Apps review-card capabilities. The solana/jupiter package contains live Jupiter route discovery plus unsigned symbol- and mint-based swap creation. Both packages receive the authenticated user only through the route's verified MCP context; neither has a private key or can sign or broadcast a transaction.

hylo/core is a Solana protocol plugin focused on Hylo operations. create_hylo_buy_asset and create_hylo_sell_asset create Jupiter-routed unsigned transactions into or out of live Hylo mints such as hyUSD, eHYUSD, hyloSOL, hyloSOL+, xSOL, and cbBTC. The tools reuse the same five-minute, account-owned review/sign flow as Solana swaps; MCPBuddy never receives a private key or broadcasts before wallet review. list_hylo_assets returns the supported Hylo symbols/mints catalog, while get_hylo_asset_balances reads the current account's bound wallet for nonzero Hylo token holdings. get_hylo_operation_guide is the single guide-style helper for choosing the right operation. Native Hylo mint/earn/leverage builders are intentionally not exposed until backed by a verified Hylo SDK/API integration.

The base package also supports create_solana_sol_transfer(recipient, amount) for native SOL. It creates the same five-minute, account-owned unsigned review record as an SPL transfer. The Jupiter package offers quote_solana_swap(inputToken, outputToken, amount, slippageBps) for a read-only expected/minimum-output quote before create_solana_swap; quoting does not create any pending transaction. See plugin development for package boundaries and the checklist for adding tools.

Call list_solana_swap_tokens() before creating a trade. It returns the supported mainnet assets with their stable symbols, mint addresses, and decimals. The public MCP tool create_solana_swap(inputToken, outputToken, amount, slippageBps) accepts those symbols (for example, SOL, USDC) and a human-readable decimal amount (for example, "0.1"), so an external AI never has to guess a mint or its decimal precision. The server only permits tokens in this allowlist, converts the amount exactly to atomic units, and builds a Jupiter-routed swap for the account's bound wallet. The tool has no signing key and never broadcasts a transaction.

It instead creates a five-minute pending item under Account → Pending swaps. Solana transaction blockhashes are much shorter-lived, so MCPBuddy refreshes an older transaction immediately before signing and asks the user to review the refreshed quote; it never silently changes a transaction that is about to be signed. The signing queue shows the payment, expected and minimum received amount, slippage, fee payer, involved program count, route, and a SHA-256 transaction-message fingerprint. The wallet signs the exact Solana message bytes offline; MCPBuddy verifies the 64-byte signature against the bound wallet, attaches it to the server-stored wire transaction, then broadcasts those exact reviewed bytes. See offline-signing design for the protocol and security invariants.

Run drizzle/0006_swap_transactions.sql before enabling this feature. Configure SOLANA_RPC_URL with a production RPC endpoint. JUPITER_API_KEY is optional for Jupiter API plans that require it; it is sent only server-to-server.

Before enabling Google login, run drizzle/0003_auth_identities.sql in the Vercel Postgres SQL editor. It preserves existing GitHub accounts and adds provider-specific identity mapping.

MCP interactive UI practice

create_solana_swap is an end-to-end MCP Apps example. Its tool declaration advertises a ui://mcpbuddy/swap-review.html resource through openai/outputTemplate (and ui/resourceUri for other compatible clients). The resource delivers a sandboxed HTML review card; the tool result carries a short model-visible summary plus structuredContent for the card. Clients without MCP Apps UI support retain the same text-only workflow. See MCP UI return and deep-link flow for the complete design.

Try it with an authenticated MCP client:

1. Call list_solana_swap_tokens() and select two returned symbols.
2. Call create_solana_swap, for example with SOL, USDC, "0.01", and 50 basis points.
3. Verify that an Apps-capable client renders the unsigned-swap review card. Its action only opens MCPBuddy’s Account page.
4. Inspect the persisted pending swap and sign using the connected wallet. The component never receives a key, transaction bytes, or a signing capability.