nidhipati — proof of spend for AI agents

Check a signed proof-of-spend receipt offline: schema, Ed25519 signature, mandate expiry, positive amount, quantity*unit_price == amount, refund not above payment. Use when an agent or provider returns a receipt and you need to know whether it actually proves the charge was allowed. Do NOT use to move funds or to confirm a transaction on-chain - nothing here reads a chain.

{
  "type": "object",
  "properties": {
    "receipt": {
      "type": "object",
      "description": "The receipt document as JSON."
    },
    "public_key": {
      "type": "string",
      "description": "Ed25519 public key, base64url (from keygen) or 64 hex chars."
    }
  },
  "required": [
    "receipt",
    "public_key"
  ]
}

Find duplicates, price escalation, failed-but-billed calls, runaway loops, missing refunds, model overpay, unknown asset/network and budget breaches in a list of settled agent calls. Returns three separate amounts (money without a basis, estimate above the agent's own median, budget overrun) instead of one sum, because adding them together would overstate what can be recovered. Do NOT use as a statement of money actually returned.

{
  "type": "object",
  "properties": {
    "records": {
      "type": "array",
      "description": "Rows with ts, agent_id, tool, quote, settled, status; optional model, actual, refund, asset, network, tx_hash, payee.",
      "items": {
        "type": "object"
      }
    },
    "policy": {
      "type": "object",
      "description": "Optional budget policy: {\"limit_usd\": \"100\"}."
    }
  },
  "required": [
    "records"
  ]
}

Turn an issuer's reserve lines into a NAV with explicit formulas and a sha256 evidence hash per line. Verdict is backed, underbacked, or incomplete - and the backing ratio is refused (null) when any line has no price, because a ratio over half a reserve is not a number. Do NOT treat the result as a statutory audit.

{
  "type": "object",
  "properties": {
    "reserve": {
      "type": "object",
      "description": "Reserve document."
    }
  },
  "required": [
    "reserve"
  ]
}

Weigh the sources a resolver says it read against the declared outcome. Verdicts: supported, disputed, single_source, insufficient. A conflict is reported as a conflict, never averaged. Do NOT use to trade or to place a position.

{
  "type": "object",
  "properties": {
    "market": {
      "type": "object",
      "description": "Market document."
    }
  },
  "required": [
    "market"
  ]
}

Match invoices to stablecoin transfers by memo first, then exact amount and asset inside the invoice window. Names what is left over in both directions: invoices nobody paid, money nobody invoiced, invoices paid twice. A duplicate is counted once, never twice. Do NOT use as proof of who the payer was.

{
  "type": "object",
  "properties": {
    "invoices": {
      "type": "array",
      "items": {
        "type": "object"
      },
      "description": "id, amount, asset, created_at; optional due_at, payee, memo."
    },
    "transactions": {
      "type": "array",
      "items": {
        "type": "object"
      },
      "description": "tx_hash, amount, asset, timestamp; optional to, memo."
    }
  },
  "required": [
    "invoices",
    "transactions"
  ]
}