Dagon Inference MCP server

A stdio Model Context Protocol server for Dagon Inference: list models, check a balance, create keys, buy credits with USDC on Solana, and chat.

MIT licensed.

Dagon Inference serves uncensored (abliterated) open-weight LLMs through an OpenAI-compatible API, paid with USDC on Solana. This server lets an MCP client (Claude Desktop, Claude Code, Cursor, ...) use it directly. Needs Node 22.18 or newer; no install step:

npx -y dagon-mcp

Get an account key with the dagon_create_key tool or at https://inference.dagon.so.

No MCP client? An agent can pay per request with x402 instead: send the request with no key, sign the USDC transfer the 402 asks for, retry, and keep the key returned in x-dagon-key. No key, no SOL, no install beyond an x402 client such as @x402/fetch with @x402/svm. This server does not pay with x402; it uses keys and the wallet purchase below.

Tools

Balance and chat use DAGON_API_KEY by default and accept an api_key argument. Purchases and confirmations never accept an account override: they always use the server's configured DAGON_API_KEY, so a tool caller cannot redirect a configured wallet's payment to another account.

Buying credits

dagon_buy_credits calls POST /v1/credits/purchase, then POST /v1/credits/purchase/confirm (guide).

Before any gateway call, the amount must be at least DAGON_MIN_PURCHASE_USD (default $1), within DAGON_MAX_PURCHASE_USD (per call, default $50), together with purchases this server process has already prepared within DAGON_MAX_PURCHASE_USD_PER_SESSION (default $200), and together with everything prepared today (UTC) by any server process sharing the spend ledger within DAGON_MAX_PURCHASE_USD_PER_DAY (default $200). Requests outside these limits fail with a tool error and create nothing. Purchases the gateway did not create do not count. The session total resets when the MCP server restarts; the daily total does not, because it is kept in DAGON_SPEND_LEDGER (default %APPDATA%\dagon-mcp\spend-ledger.json on Windows, $XDG_CONFIG_HOME/dagon-mcp/spend-ledger.json or ~/.config/dagon-mcp/spend-ledger.json elsewhere; written with mode 0600 where supported). An unreadable or corrupt ledger refuses purchases. DAGON_TREASURY_WALLET is required for every purchase, with or without a wallet.

When the gateway does not sponsor the network fee, the payer's worst-case SOL cost (5,000 lamports per signature, the compute-budget priority fee, and 0.00203928 SOL rent whenever the transaction creates the treasury's USDC account) is counted against DAGON_MAX_SOL_FEES per UTC day (default 0.05 SOL) in the same ledger; a purchase that would exceed it is refused unsigned. An invalid limit stops the server at startup.

• DAGON_WALLET_SECRET_KEY set: DAGON_API_KEY and DAGON_TREASURY_WALLET are also required. The server first proves that the returned transaction (legacy or v0 message) is exactly the payment the payment service builds: one USDC TransferChecked of the requested amount from the configured wallet's associated token account to the configured treasury's associated token account, one SPL Memo whose data is the purchase_id, and at most one idempotent creation of the treasury's USDC account whose rent is paid by the fee payer. It rejects mismatched response metadata, amounts, mint, token program, destination, memo, blockhash, fee-payer or signer roles, lookup tables, duplicate keys, unrelated instructions, accounts or writable authorities; a sponsor fee payer may appear in no instruction except as that rent payer. Only bounded Solana compute-budget instructions may also accompany the transfer. After validation it signs as the wallet. A fee-sponsored transaction carries no fee payer signature: the server does not submit it but sends it to the gateway's confirm as signed_transaction, and the payment service adds its fee payer signature and submits it. Otherwise it submits through DAGON_SOLANA_RPC_URL and confirms with the signature. Either way it confirms the purchase for at most 45 seconds; past that it reports the purchase as pending. Once the payment may be on-chain, every result and error names the purchase_id and the transaction signature (or, when fee sponsored, the signed transaction): do not buy again, pass them to dagon_confirm_purchase. The wallet needs the USDC, and SOL for the fee only when the purchase is not fee sponsored. Give the client a tool timeout of at least 90 seconds; cancelling the tool call stops the wait.
• No wallet: pass payer_wallet. The server runs the same byte-level validation with payer_wallet as payer and transfer authority, and only then returns the unsigned base64 transaction, naming the treasury it pays and the SOL it can cost. A transaction that fails validation is never returned. Sign it with that wallet before it expires, without rebuilding it. When fee_sponsored is true, do not submit it: call dagon_confirm_purchase with purchase_id and signed_transaction (the base64 wallet-signed transaction). Otherwise submit it, then call dagon_confirm_purchase with purchase_id and its signature.

The secret key never leaves the server process and is never echoed, including in errors. At startup the server prints the derived payer address to stderr; check it is the wallet you meant. The trusted treasury address is configured independently rather than accepted from the gateway response. Use a dedicated hot wallet holding only what you intend to spend.

Every gateway and Solana RPC request is aborted after 30 seconds or when the client cancels the tool call, and gateway responses larger than 4 MiB are refused.

Configuration

Install

Claude Code

claude mcp add dagon --env DAGON_API_KEY=gk_... -- npx -y dagon-mcp

Claude Desktop

Add to claude_desktop_config.json (Settings → Developer → Edit Config); write the values themselves:

{
  "mcpServers": {
    "dagon": {
      "command": "npx",
      "args": ["-y", "dagon-mcp"],
      "env": {
        "DAGON_API_KEY": "gk_...",
        "DAGON_TREASURY_WALLET": "9rMdbu4KdLWH2nPXbzhm9HTKaibGZ2ckakQbW1wPh6KK"
      }
    }
  }
}

On Windows, if npx is not found, use "command": "cmd", "args": ["/c", "npx", "-y", "dagon-mcp"].

Cursor

~/.cursor/mcp.json (global) or .cursor/mcp.json (project):

{
  "mcpServers": {
    "dagon": {
      "command": "npx",
      "args": ["-y", "dagon-mcp"],
      "env": { "DAGON_API_KEY": "gk_..." }
    }
  }
}

Project .mcp.json, omp

Claude Code and omp expand ${VAR} from your environment, so secrets stay out of the file:

{
  "mcpServers": {
    "dagon": {
      "command": "npx",
      "args": ["-y", "dagon-mcp"],
      "env": {
        "DAGON_API_KEY": "${DAGON_API_KEY}",
        "DAGON_WALLET_SECRET_KEY": "${DAGON_WALLET_SECRET_KEY:-}",
        "DAGON_TREASURY_WALLET": "${DAGON_TREASURY_WALLET:-}"
      },
      "timeout": 120000
    }
  }
}

timeout is omp's per-tool timeout in milliseconds; drop it for clients that do not use it.

Security

• DAGON_WALLET_SECRET_KEY is optional. Without it the server never signs anything: it returns validated unsigned transactions for you to sign with your own wallet. With it, use a dedicated hot wallet holding only what you intend to spend; the key never leaves the process and is never echoed.
• DAGON_TREASURY_WALLET is the trust anchor for purchases: every transaction is checked byte-for-byte to pay exactly that treasury, so a compromised or spoofed gateway cannot redirect funds. The published Dagon treasury is 9rMdbu4KdLWH2nPXbzhm9HTKaibGZ2ckakQbW1wPh6KK; take it from this README or https://inference.dagon.so, not from a tool result.
• Per-call, per-session and per-day USD caps and a daily SOL fee cap bound what any tool caller can spend.
• Purchases always credit the configured DAGON_API_KEY; a tool caller cannot redirect them to another account.

Development

git clone https://github.com/inkwell-finance/dagon-mcp.git
cd dagon-mcp
npm ci
npm run check   # type-check
npm test        # tool tests against a mocked fetch; no network
npm run build   # compile to dist/

License

MIT © Inkwell Finance, Inc. d/b/a Dagon