@priors/mcp

An MCP server that gives an AI assistant (Claude Desktop, Claude Code, or any MCP client) a USDG wallet on Robinhood Chain: pay x402-priced APIs, check balances, read any agent's Priors credit record, and borrow from and repay the agent's own Priors line.

Just reading? Use the hosted server

No install and no key: https://mcp.priors.trade/mcp (Streamable HTTP) answers the read-only questions (an agent's record and score, the pool's figures, recent loans, the facilitator's services) from the same public data as priors.trade. It holds no key and cannot send a transaction.

claude mcp add --transport http priors https://mcp.priors.trade/mcp

or, in any client that takes a remote server: { "mcpServers": { "priors": { "url": "https://mcp.priors.trade/mcp" } } }.

This package is the other half: a local server with the agent's wallet behind it, for paying, borrowing and repaying.

| tool | what it does | needs the key | |---|---|---| | pay_url(url, method?, body?, max_price_usd?, max_borrow_usd?) | fetch an https URL, pay its x402 402 in USDG if the price is ≤ max_price_usd (default $0.10); borrows the gap only if max_borrow_usd is given. Refuses private and local addresses, never follows a redirect, answers within 45 s, and never signs a second payment for a purchase (the same method, URL and body) that is still pending, until its validBefore plus 60 s (a new call resends the same one, also after a restart, in a new session or from another session of the same wallet: see PRIORS_STATE_DIR) | yes | | wallet_balance(address?) | USDG and gas ETH of the wallet (or any address) | no (with address) | | credit_status(agent_id?) | line, drawn, available, backer, record, score, open loans and due dates; on a stock line, the stock tokens behind it, and available capped by what the stock vault lets it draw | no (with agent_id) | | stock_assets(symbol?) | the stock tokens the Priors stock vault accepts: live Chainlink price, whether it lends against each now (or why not: a sharp price move, a multiplier change, a paused or blocked token), loan-to-value | no | | stock_position(agent_id?) | the stock tokens behind an agent's stock line: amount, what the vault values them at, loan-to-value, what the line can draw now, any lending hold | no (with agent_id) | | borrow(amount_usd, days, dry_run?) | borrow USDG from the line into the wallet; both amounts required; dry_run quotes the fee. A borrow sent whose answer is lost is counted and said to be possibly open (check credit_status) | yes | | repay(loan_id? \| all) | repay one of the agent's own loans, or all of them earliest due first; another agent's loan is refused | yes | | score_of(agent_id) | any agent's on-chain score (0 to 1000) and repayment record, plus its Priors Score v2 and trust rung when published | no | | find_services(query?) | services registered with the Priors facilitator that accept USDG (GET /merchants), each marked as approved by Priors or self-registered and not reviewed | no |

Tools that move money state the amounts in their answer, are marked destructive for MCP clients, and their descriptions tell the assistant to confirm with you first. Merchant text (response bodies, listings, redirect targets) comes back between random <<merchant-data …>> markers, as data. They act on Robinhood Chain mainnet.

Configure

The only secret is the wallet key, and it is read from the environment variable PRIORS_KEY, never from the command line (a key-shaped argument makes the server exit without starting) and never printed or returned by a tool. Use a dedicated agent wallet holding only what the agent may spend.

| variable | default | | |---|---|---| | PRIORS_KEY | none | the agent wallet's private key; without it only the read-only tools work | | PRIORS_AGENT_ID | looked up from the identity registry | the Priors agent id the wallet acts for (the lookup finds only identities minted to the wallet since the v2 deploy, never one transferred to it; set it for an older or a bought one, or when the wallet holds several) | | PRIORS_RPC | https://rpc.mainnet.chain.robinhood.com | JSON-RPC endpoint (a private URL is redacted from every answer) | | PRIORS_FACILITATOR | https://facilitator.priors.trade | where find_services lists merchants | | PRIORS_MAX_PRICE_USD | 1.00 | ceiling on what pay_url may be told to pay per call | | PRIORS_MAX_BORROW_USD | 25 | ceiling on borrow and on pay_url's max_borrow_usd | | PRIORS_MAX_SPEND_USD | 5 | most pay_url may sign in total while the server runs (counted when signed) | | PRIORS_MAX_BORROW_TOTAL_USD | 25 | most borrow and pay_url may borrow in total while the server runs (a borrow sent whose answer was lost counts: it may have opened a loan) | | PRIORS_ALLOW_LOCAL | off | 1 lets pay_url reach http://localhost and private addresses (local testing only) | | PRIORS_SCORE_V2 | https://priors.trade/api/score-v2 | where score_of reads Priors Score v2; off shows the on-chain score only | | PRIORS_STOCK_VAULT | the bundled deployments file's stockVault | the stock vault the stock tools and credit_status read | | PRIORS_STATE_DIR | ~/.local/state/priors-mcp | where the payments signed and not yet settled are kept (one owner-only file per wallet, never the key, with a short-lived .lock beside it while it is written), so a restart, a new session or another session of the same wallet resends them instead of signing again. An absolute path, or one starting with ~/ (a relative one is refused at start). A payment that cannot be written there is not sent. off keeps them in memory only |

Contract addresses (pool, lens, registry, USDG) come from deployments/4663.v2.json, bundled in the package, and the accepted stock tokens from deployments/stock-assets.4663.json. The stock vault's address (live since 2026-09-28) comes from the same deployments file, or from PRIORS_STOCK_VAULT.

Claude Desktop

Settings → Developer → Edit Config (claude_desktop_config.json), then restart Claude Desktop:

{
  "mcpServers": {
    "priors": {
      "command": "npx",
      "args": ["-y", "@priors/[email protected]"],
      "env": {
        "PRIORS_KEY": "0xYOUR_AGENT_WALLET_KEY",
        "PRIORS_AGENT_ID": "1234"
      }
    }
  }
}

Read-only (no wallet): leave out env. From a checkout of the Priors repository instead of npm (run npm install at its root first): "command": "node", "args": ["/path/to/priors/packages/mcp/bin/priors-mcp.mjs"].

Claude Code

A project .mcp.json that reads the key from your shell's environment, so the file itself holds no secret:

{
  "mcpServers": {
    "priors": {
      "command": "npx",
      "args": ["-y", "@priors/[email protected]"],
      "env": {
        "PRIORS_KEY": "${PRIORS_KEY}",
        "PRIORS_AGENT_ID": "${PRIORS_AGENT_ID:-}"
      }
    }
  }
}

or, for your user only: claude mcp add priors --scope user -e PRIORS_KEY="$PRIORS_KEY" -- npx -y @priors/[email protected] (the key is expanded by your shell from the environment; do not paste it on the command line).

Try it

"What's the Priors score of agent 6228?" · "How much USDG does my wallet hold?" · "Find services that sell token prices" · "Pay https://api.example.com/report, up to 5 cents" · "Borrow $5 for 7 days, show me the fee first".

Source

github.com/priors-agents/priors, MIT.