x402 List

x402 Protocol Service Directory

XFuel

AI PAYMENT-READY

payment-ready until 2026-09-01

OpenAI-compatible paid inference via x402. POST /v1/chat/completions. $0.01 USDC on Base and Solana. Returns a signed public receipt.

Pay from $0.01 per request in USDC on Base / Solana, settled onchain via the x402 protocol, no signup, no API key needed.

listed 2026-08-25 · no on-chain settlement recorded yet

BASE URL https://api.xfuel.app WEBSITE https://xfuel.app ENDPOINTS 1 NETWORK Base / Solana ASSET USDC MEMBER SINCE 2026-08-25

VERDICT

ranking generation 3

Not yet ranked: too little of this service has been measured to place it against the rest of AI. We show no score rather than one assembled out of defaults.

ALTERNATIVES IN AI

Other AI services in this directory, ordered by the same measured score. The figures are ours: 30-day uptime from our own probes, 30-day settlement volume read on-chain (a conservative undercount, and null where we cannot measure it, never a zero).

Ranked alternative x402 services in the same category, with band, measured score, 30-day uptime and 30-day on-chain settlement volume
SERVICE BAND SCORE UPTIME 30D VOL 30D
x402engine solid 93 100% $23.34
Agent402.tools solid 92 98.2% $70.37
vaaya solid 91 100% $27.55
Otto AI solid 91 100% $60.72
StableEmail solid 90 100% $26.16
5 of 93 other ranked services in AI · see the whole category

ASSESSMENT

updated 30m ago

The parts the verdict above is computed from, each with its proof. Click any chip. Measured values stay read-only; unknown is honest, and an unknown is never counted as a zero.

reliability -
uptime 24h
-
uptime 7d
-
uptime 30d
-
uptime 90d
-
response p95
-
avg response
-
total checks
0

Measured on the unpaid 402 handshake, not the paid call. A service can 402 correctly and still fail after payment.

compliance unknown

x402 compliance not evaluated yet.

jump to compliance checklist

price $0.01 (p44 in AI)
price (min)
$0.01
category percentile (min)
p44 in AI
endpoints / prices
1 / 1
model
flat
stability
100%
risk clean

No deterministic risk flag. Risk fires only on an exact blocklist match, or a reserved-brand name with a mismatched verified payTo. Never from low uptime, a high price, or a model guess.

domain age
258d
registrar
Namecheap Inc.
hosting
custom
domain created
2025-12-09

Identity facts, not a risk score.

traction $0.00 30d · 0 buyers
volume 30d
$0.00
buyers 30d
0
settlements 30d
0
measured since
--- (start of our harvest window)
last settlement
---
top buyer share
-
trend 7d vs 30d
-
networks
eip155:8453, solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdpKuc147dw2N9d
volume all-time
$0
settlements all-time
0
median settlement 30d
-
max settlement 30d
-
settled via
-

Conservative undercount: only USDC settlements via facilitators we measure are counted. A measured floor, not an estimate.

Top buyer share is a concentration signal, not part of the ranking score.

WHAT IT DOES

ai-derived

No AI synthesis has been produced for this service yet.

ENDPOINTS

Service endpoints with HTTP method, path, description, pricing, and network
METHOD PATH DESCRIPTION PRICE NETWORK ASSET 402 CHANNEL
GET /v1/chat/completions $0.01 Base/Solana USDC header
1 endpoints

REQUEST / RESPONSE EXAMPLE

An unpaid request to GET /v1/chat/completions returns HTTP 402 with the payment terms. Settle onchain via your facilitator, then retry with the X-Payment header.

// request
curl -i 'https://api.xfuel.app/v1/chat/completions'
// 402 response (captured by monitor) · 1 payload · click to expand
[
  {
    "error": "Payment required",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "nonce": "0x2d122724c438ad8c1baf43a061e03b41bcb655a1c2144618aa69a7a6bbdd6a4f",
          "taskId": "openai-d598fdf7-ba2d-4a6b-8e4a-630c498b609d",
          "version": "2",
          "expiresAt": 1787643360821
        },
        "payTo": "0x23f713411c30BBd9A989c9cbC22EB0b55F7f7334",
        "amount": "10000",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxAmountRequired": "10000",
        "maxTimeoutSeconds": 120
      },
      {
        "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
        "extra": {
          "nonce": "0x6fdc1b72c7cdbf50fc9414dc4014ee0a63b602a157b317e41775aea11c01b794",
          "taskId": "openai-d598fdf7-ba2d-4a6b-8e4a-630c498b609d",
          "feePayer": "CjNFTjvBhbJJd2B5ePPMHRLx1ELZpa8dwQgGL727eKww",
          "expiresAt": 1787643360821
        },
        "payTo": "58Qo8QTJ1Sd4aXSygwAeBLNL3VrXRmfUCceB6b5RJCx6",
        "amount": "10000",
        "scheme": "exact",
        "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
        "maxAmountRequired": "10000",
        "maxTimeoutSeconds": 120
      }
    ],
    "resource": {
      "url": "https://api.xfuel.app/v1/chat/completions",
      "tags": [
        "llm",
        "openai-compatible",
        "chat-completions",
        "inference"
      ],
      "iconUrl": "https://api.xfuel.app/xfuel-icon.svg",
      "mimeType": "application/json",
      "description": "OpenAI-compatible paid inference via x402 USDC on Base and Solana ($0.01). POST /v1/chat/completions is the recommended surface. Returns signed receipt + public verify_url. Paying this host is real mainnet USDC.",
      "serviceName": "XFuel"
    },
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "body": {
              "model": "xfuel/auto",
              "messages": [
                {
                  "role": "user",
                  "content": "Hello"
                }
              ],
              "max_tokens": 500
            },
            "type": "http",
            "method": "POST",
            "bodyType": "json"
          },
          "output": {
            "type": "json",
            "example": {
              "id": "chatcmpl-abc123",
              "model": "xfuel/auto",
              "usage": {
                "total_tokens": 15,
                "prompt_tokens": 10,
                "completion_tokens": 5
              },
              "xfuel": {
                "verify_url": "https://api.xfuel.app/receipt/openai-abc123"
              },
              "object": "chat.completion",
              "choices": [
                {
                  "index": 0,
                  "message": {
                    "role": "assistant",
                    "content": "Hello!"
                  },
                  "finish_reason": "stop"
                }
              ],
              "created": 1700000000
            }
          }
        },
        "schema": {
          "type": "object",
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "required": [
            "input"
          ],
          "properties": {
            "input": {
              "type": "object",
              "required": [
                "type",
                "method",
                "bodyType",
                "body"
              ],
              "properties": {
                "body": {
                  "type": "object",
                  "required": [
                    "messages"
                  ],
                  "properties": {
                    "model": {
                      "type": "string",
                      "description": "Model id from GET /v1/models; xfuel/auto routes automatically"
                    },
                    "stream": {
                      "type": "boolean"
                    },
                    "messages": {
                      "type": "array",
                      "items": {
                        "type": "object",
                        "required": [
                          "role",
                          "content"
                        ],
                        "properties": {
                          "role": {
                            "enum": [
                              "system",
                              "user",
                              "assistant"
                            ],
                            "type": "string"
                          },
                          "content": {
                            "type": "string"
                          }
                        }
                      },
                      "description": "OpenAI-style chat messages array"
                    },
                    "max_tokens": {
                      "type": "integer",
                      "description": "Output token budget"
                    },
                    "temperature": {
                      "type": "number",
                      "maximum": 2,
                      "minimum": 0
                    }
                  }
                },
                "type": {
                  "type": "string",
                  "const": "http"
                },
                "method": {
                  "enum": [
                    "POST",
                    "PUT",
                    "PATCH"
                  ],
                  "type": "string"
                },
                "bodyType": {
                  "enum": [
                    "json",
                    "form-data",
                    "text"
                  ],
                  "type": "string"
                }
              },
              "additionalProperties": false
            },
            "output": {
              "type": "object",
              "required": [
                "type"
              ],
              "properties": {
                "type": {
                  "type": "string"
                },
                "example": {
                  "type": "object"
                }
              }
            }
          }
        }
      }
    },
    "x402Version": 2
  }
]

OVER TIME

All charts use the 30d selector; each series spans only the dates it has data for. Every series is also served as JSON at /api/v1/services/xfuel/price, /scores, /volume and /buyers. On-chain volume and distinct buyers are measured over the service's settlement address and are a conservative undercount (only settlements that reach a measured facilitator are counted). The on-chain series roll up hourly, so the latest day can be up to about an hour behind; distinct buyers are counted per payout address, so a service that settles to more than one address is an upper bound.

UPTIME
no data
30d UPTIME -
RESPONSE TIME
no data
AVG RESP 904ms
PRICE (captured 402, USD)
building price history ($0.01)
SUB-SCORES (uptime + x402 compliance)
building assessment history

checklist grew 11->14 on 2026-07-28; a step here is a metric change, not a regression

VOLUME (on-chain settlement, USD)
no on-chain volume yet
DISTINCT BUYERS
no distinct buyers yet

COMPLIANCE

not evaluated

last 402 captured 2026-08-25 · last up 2026-08-25

  • 402 payload captured
  • accepts[] array present
  • payTo address recoverable
  • payTo at accepts[0].payTo (conformant shape)
  • payTo is a valid on-chain address
  • atomic price declared
  • atomic price in a sane range
  • asset (token) address declared
  • network resolves to CAIP-2
  • payment scheme declared
  • served over HTTPS
  • declares the current x402 version (2)
  • EIP-712 domain parameters present on every EVM entry
  • x402 v2 envelope delivered in the payment-required header

SITE PILLARS

  • homepage reachable
  • openapi doc
  • pricing page
  • llms.txt
  • robots.txt
  • terms page
recent checks (2) live · click to expand
TIME STATUS RESP CAUSE
● OK 1043ms
● OK 765ms

EMBED THIS BADGE

Show that XFuel is monitored on x402-list. Paste this on your site or README, it links back to this live listing.

XFuel listed on x402-list
status
XFuel uptime on x402-list
live uptime
// HTML
<a href="https://x402-list.com/services/xfuel?utm_source=badge&utm_medium=referral&utm_campaign=embed">
  <img src="https://x402-list.com/badge/xfuel.svg" alt="XFuel listed on x402-list" height="28">
</a>
// Markdown
[![XFuel on x402-list](https://x402-list.com/badge/xfuel.svg)](https://x402-list.com/services/xfuel?utm_source=badge&utm_medium=referral&utm_campaign=embed)
// HTML · live uptime variant
<a href="https://x402-list.com/services/xfuel?utm_source=badge&utm_medium=referral&utm_campaign=embed">
  <img src="https://x402-list.com/badge/xfuel.svg?data=uptime" alt="XFuel uptime on x402-list" height="28">
</a>

RUN THIS SERVICE?

Keep this listing accurate: propose changes to the name, description, website, category or add new endpoints to monitor. Ownership is verified with a domain proof and every change is reviewed manually; measured data stays read-only.

[ update this listing ]

Earn the verified tier: x402list pays a real call to this endpoint and, if it delivers, the service is delivery-verified. The fee covers the cost of the probe, not the badge; there is no refund if the call does not deliver. Agent and API only, no in-browser signing. See /api.

[ verify this service ($0.25) ]

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