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spendctl

dev.spendctl/spendctl · v0.1.0

Measured by MCP Station

Description written by the publisher, not verified

Spend policy for AI agents that pay (x402, MPP). Login-free sandbox, real sidecar, no real funds.

Connect

claude mcp add --transport http spendctl https://mcp.spendctl.dev/mcp

{
  "mcpServers": {
    "spendctl": {
      "url": "https://mcp.spendctl.dev/mcp"
    }
  }
}

Tools as reported by the server

• sandbox_create
  Creates an isolated spendctl sandbox and returns its sandbox_id. Call it first: every other tool needs the sandbox_id, and one sandbox serves a whole conversation (create another only to try a different preset). The sandbox is a real spendctl sidecar with a throwaway wallet, a mock x402 facilitator
• sandbox_pay
  Fetches one of the sandbox's paid endpoints (HTTP 402, x402) through the spendctl sidecar, which applies the sandbox agent's budget, allowlist and approval policy, pays with the throwaway wallet if allowed, and returns the response. Use it for every paid call in the sandbox: with dryRun to see the d
• check_budget
  Shows the sandbox agent's spending limits, what has been spent in each window and what is left. Use it before a paid call when the remaining budget matters, or after a refusal to see which limit was hit. Returns the agent name and mode, the per-request limit, the approval threshold, what happens whe
• list_receipts
  Lists the sandbox agent's most recent payment attempts, newest first: paid (amount and mock transaction hash), refused (reason codes) and waiting for approval. Use it to report what happened so far or to find a receipt id; after a hold, the approval id is in the sandbox_pay result. Returns up to `li
• get_policy
  Returns the sandbox's spendctl.yaml as text: the preset name and the agent's budgets, allowed hosts and approval rules. Use it to explain why a payment was refused or held, or to show what a spendctl policy file looks like. Read-only; the sandbox policy cannot be changed, create a sandbox with anoth
• approve
  Approves or denies a payment that sandbox_pay reported as waiting for approval, as the human approver would with `spendctl approve`. Use it only with an approval id from this sandbox; in the real product a human decides, in the sandbox the model plays that role. Returns the approval id and its new s

Website · JSON · Text for agents · Registry updated 2026-10-26