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EVM Nonce Gap Check: calculates the gap between pending and proposed transaction nonces…

Name: EVM Nonce Gap Check: calculates the gap between pending and proposed transaction nonces us
Price: 0.001 USD
Availability: InStock

by api.delx.ai · discovered, not yet claimed by its owner · updated 2026-10-08

30d calls3

30d payers3

MethodPOST

Outputjson

Mirrored from Coinbase's public x402 Bazaar. The description is the provider's own text and has not been reviewed here; the payment requirements are copied as published.

What it does

EVM Nonce Gap Check: calculates the gap between pending and proposed transaction nonces using only bounded caller-supplied values. Call when you need a bounded evm nonce gap check result before signing, submitting, replacing, or accepting an EVM/Base transaction assembled from caller-owned data. Returns normalized transaction evidence, calculated budget or shape findings, and a fail-closed preflight status for EVM Nonce Gap Check as versioned deterministic JSON. Price: $0.001 USDC via x402 on B…

Tags: base · evm · preflight · bazaar · payment-identifier

Call contract

Method: POST
Input: json
Output: json
Last paid call: 2026-10-08

Input example from Bazaar metadata

{
  "maximum_gap": 1,
  "pending_nonce": 12,
  "proposed_nonce": 14
}

Output example

{
  "evidence": {
    "external_calls": 0,
    "input_sha256": "b9889d09b1009c8b22542a020475a3b907ede762b24f2fafec69d286c024edfd",
    "retained": false
  },
  "operation": "evm_preflight:evm_nonce_gap_check",
  "result": {
    "gap": 2,
    "possible_replacement": false,
    "within_budget": false
  },
  "schema": "delx/util-evm-nonce-gap-check/v1",
  "status": "advisory"
}

Use with an agent

Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
Inspect. Fetch /resources/31122.json for the price and payment options.
Pay. Call GET https://api.delx.ai/api/v1/x402/evm-nonce-gap-check. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
Execute. The provider returns 200 with the data. Agent Bazaar is not in the request path and never sees your payment.

For humans

You don't need an account or an API key; you need a wallet holding a small amount of USDC on Base, Solana, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.001 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base, Solana
Demand: 3 calls · 3 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

Scheme	Network	Asset	Amount	Pay to	Timeout
exact	Base eip155:8453	USDC	$0.001	0x9f8bd9875b3E0b632a24A3A7C73f7787175e73A2	300s
exact	Base eip155:8453	USDC	$0.001	0x9f8bd9875b3E0b632a24A3A7C73f7787175e73A2	300s
exact	Solana solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp	USDC	$0.001	28heAMpFkeUJsL7o7apiK4oJwZWq2fUHinRwbgYYsemG	300s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x9f8bd9875b3E0b632a24A3A7C73f7787175e73A2",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "1000",
    "amountUsd": 0.001,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x9f8bd9875b3E0b632a24A3A7C73f7787175e73A2",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "1000",
    "amountUsd": 0.001,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "payTo": "28heAMpFkeUJsL7o7apiK4oJwZWq2fUHinRwbgYYsemG",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "1000",
    "amountUsd": 0.001,
    "maxTimeoutSeconds": 300
  }
]

Schemas

Output schema (JSON Schema)

{
  "additionalProperties": true,
  "description": "Versioned bounded first-party JSON result with input evidence; caller data is processed in memory and not retained.",
  "properties": {
    "evidence": {
      "additionalProperties": true,
      "properties": {
        "external_calls": {
          "type": "integer"
        },
        "input_sha256": {
          "type": "string"
        },
        "retained": {
          "type": "boolean"
        }
      },
      "type": "object"
    },
    "operation": {
      "type": "string"
    },
    "result": {
      "additionalProperties": true,
      "properties": {
        "gap": {
          "type": "integer"
        },
        "possible_replacement": {
          "type": "boolean"
        },
        "within_budget": {
          "type": "boolean"
        }
      },
      "type": "object"
    },
    "schema": {
      "type": "string"
    },
    "status": {
      "type": "string"
    }
  },
  "type": "object"
}

Example shape — generated from the schema, not a captured live response

{
  "evidence": {
    "external_calls": 0,
    "input_sha256": "string",
    "retained": true
  },
  "operation": "string",
  "result": {
    "gap": 0,
    "possible_replacement": true,
    "within_budget": true
  },
  "schema": "string",
  "status": "string"
}

Examples

curl

curl "https://api.delx.ai/api/v1/x402/evm-nonce-gap-check"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

JavaScript

const res = await fetch("https://api.delx.ai/api/v1/x402/evm-nonce-gap-check");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

Python

import httpx
res = httpx.get("https://api.delx.ai/api/v1/x402/evm-nonce-gap-check")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header

Details

Provider: api.delx.ai
Endpoint: https://api.delx.ai/api/v1/x402/evm-nonce-gap-check
Machine-readable: /resources/31122.json