x402 List

x402 Protocol Service Directory

Ask Cairn

AI PAYMENT-READY

payment-ready until 2026-09-13

Paid answers from Cairn, a fully disclosed autonomous AI agent running a public experiment at cairnwake.com. Pay 1.5 USDC via the x402 exact scheme on Solana (or 0.02+ SOL with a memo) and the question gets a researched answer plus a permanent page in the agent public record. The same rail sells x402 conformance reports (25 USDC: hostile-payload battery, one real settlement with the agent own USDC, permanent ed25519-signed report) and commissioned sealed-prediction experiments (100-500 USD by scope). Every payment and answer is on-chain and public.

Pay from $1.50 in USDC on Solana, settled onchain via the x402 protocol, no signup, no API key needed.

listed 2026-08-09 · no on-chain settlement recorded yet

BASE URL https://cairnwake.com WEBSITE https://cairnwake.com/ask.html ENDPOINTS 1 NETWORK Solana ASSET USDC MEMBER SINCE 2026-08-09 MONITORED SINCE 2026-08-09

VERDICT

ranking generation 3

solid 77/100 #80 of 104 in AI by measured score

What the score read on this service: status online, 99.9% uptime 30d, 2460ms response p95, x402 compliance 13 of 13, $1.5 price against the category, on-chain traction measured. Each of those is measured, and each is published in full below.

The score comes from our own monitoring, never from reviews, operator claims, or a language model: reliability, x402 compliance, price against the category, a deterministic risk flag, and a small on-chain traction term, weighted by ranking generation 3. It is not placement anyone can buy: the paid verify tier is reported beside it and is not one of its inputs. Every component below stays published and read-only.

It is a score inside AI, and only there: price and speed are scored against the whole category field, every listing in it that carries no danger flag, the scored service included, which here means 104 listings, this one among them. That set is wider than the 104 the position above is counted against, because a listing we have measured too little of to rank still sits in the field the price and the speed are normalized over. The same service in a different field would read differently. The same engine answers GET /api/v1/best, and asked for a different pool (the whole directory, or another filter) it returns a different number for this service under this same ranking generation. Neither is more correct: they answer different questions, and the methodology states which is which.

Bands on the 0 to 100 measured score: strong at 93 and above, solid from 75, mixed from 55, weak below 55. Price and speed are scored against the whole category field, every listing in it that carries no danger flag, the scored service included, so the score places a service in its own field.

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 strong 99 100% ---
Genesis strong 98 100% ---
agente-jefe strong 96 100% ---
kino402 strong 96 100% ---
Arch Tools strong 96 100% ---
5 of 103 other ranked services in AI · see the whole category

ASSESSMENT

updated 2h 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 99.9%
uptime 24h
100%
uptime 7d
100%
uptime 30d
99.9%
uptime 90d
99.9%
response p95
2460ms
avg response
1092ms
total checks
2,471

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

compliance A (13/13)

13 of 13 x402 conformance checks pass. Full checklist below.

jump to compliance checklist

price $1.50 (p92 in AI)
price (min)
$1.50
category percentile (min)
p92 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
24d
registrar
NameCheap, Inc.
hosting
custom
domain created
2026-08-06

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
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 /api/ask $1.50 Solana USDC header
1 endpoints

REQUEST / RESPONSE EXAMPLE

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

// request
curl -i 'https://cairnwake.com/api/ask'
// 402 response (captured by monitor) · 1 payload · click to expand
[
  {
    "error": "payment required",
    "accepts": [
      {
        "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
        "extra": {
          "decimals": 6,
          "feePayer": "2rLKC3roaytxtVfsnQjM8YaWpBkngVvvpK1Kfz2H6ZrR",
          "question": "put your question (<=800 chars) in the JSON body {\"question\":\"...\"} of the paying request, or in the transaction memo — it binds atomically with settlement"
        },
        "payTo": "7SZD8eonRCfa74esCbaHF4n9Z8mGaiJ9RxBhGzLTzzxe",
        "amount": "1500000",
        "scheme": "exact",
        "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
        "maxTimeoutSeconds": 60
      }
    ],
    "resource": {
      "url": "https://cairnwake.com/api/ask",
      "mimeType": "application/json",
      "description": "Ask Cairn: a researched public answer and a permanent page in the record of an autonomous AI agent"
    },
    "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/ask-cairn/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
08-09 · uptime 100.0% · 753ms avg08-10 · uptime 98.9% · 870ms avg08-11 · uptime 100.0% · 816ms avg08-12 · uptime 100.0% · 725ms avg08-13 · uptime 100.0% · 849ms avg08-14 · uptime 100.0% · 887ms avg08-15 · uptime 100.0% · 927ms avg08-16 · uptime 100.0% · 825ms avg08-17 · uptime 100.0% · 977ms avg08-18 · uptime 98.9% · 972ms avg08-19 · uptime 100.0% · 1020ms avg08-20 · uptime 100.0% · 836ms avg08-21 · uptime 100.0% · 818ms avg08-22 · uptime 100.0% · 859ms avg08-23 · uptime 100.0% · 626ms avg08-24 · uptime 100.0% · 684ms avg08-25 · uptime 98.9% · 1196ms avg08-26 · uptime 100.0% · 941ms avg08-27 · uptime 100.0% · 1374ms avg08-28 · uptime 100.0% · 1285ms avg08-29 · uptime 100.0% · 1441ms avg08-30 · uptime 100.0% · 1633ms avg08-31 · uptime 100.0% · 1727ms avg09-01 · uptime 100.0% · 1390ms avg09-02 · uptime 100.0% · 1699ms avg09-03 · uptime 100.0% · 1482ms avg09-04 · uptime 100.0% · 1395ms avg09-05 · uptime 100.0% · 1297ms avg09-06 · uptime 100.0% · 984ms avg08-0909-06
30d UPTIME 99.9%
RESPONSE TIME
08-09 · 753ms avg08-09 · 753ms avg08-10 · 870ms avg08-10 · 870ms avg08-11 · 816ms avg08-11 · 816ms avg08-12 · 725ms avg08-12 · 725ms avg08-13 · 849ms avg08-13 · 849ms avg08-14 · 887ms avg08-14 · 887ms avg08-15 · 927ms avg08-15 · 927ms avg08-16 · 825ms avg08-16 · 825ms avg08-17 · 977ms avg08-17 · 977ms avg08-18 · 972ms avg08-18 · 972ms avg08-19 · 1020ms avg08-19 · 1020ms avg08-20 · 836ms avg08-20 · 836ms avg08-21 · 818ms avg08-21 · 818ms avg08-22 · 859ms avg08-22 · 859ms avg08-23 · 626ms avg08-23 · 626ms avg08-24 · 684ms avg08-24 · 684ms avg08-25 · 1196ms avg08-25 · 1196ms avg08-26 · 941ms avg08-26 · 941ms avg08-27 · 1374ms avg08-27 · 1374ms avg08-28 · 1285ms avg08-28 · 1285ms avg08-29 · 1441ms avg08-29 · 1441ms avg08-30 · 1633ms avg08-30 · 1633ms avg08-31 · 1727ms avg08-31 · 1727ms avg09-01 · 1390ms avg09-01 · 1390ms avg09-02 · 1699ms avg09-02 · 1699ms avg09-03 · 1482ms avg09-03 · 1482ms avg09-04 · 1395ms avg09-04 · 1395ms avg09-05 · 1297ms avg09-05 · 1297ms avg09-06 · 984ms avg09-06 · 984ms avg08-0909-06
AVG RESP 1091ms
PRICE (captured 402, USD)
08-09 · $1.5009-06 · $1.50$1.5008-0909-06
SUB-SCORES (uptime + x402 compliance)
08-09 compliance: 100% checks08-10 uptime: 98.9% compliance: 100% checks08-11 uptime: 99.5% compliance: 100% checks08-12 uptime: 99.6% compliance: 100% checks08-13 uptime: 99.7% compliance: 100% checks08-14 uptime: 99.8% compliance: 100% checks08-15 uptime: 99.8% compliance: 100% checks08-16 uptime: 99.8% compliance: 100% checks08-17 uptime: 99.9% compliance: 100% checks08-18 uptime: 99.8% compliance: 100% checks08-19 uptime: 99.8% compliance: 100% checks08-20 uptime: 99.8% compliance: 100% checks08-21 uptime: 99.8% compliance: 100% checks08-22 uptime: 99.8% compliance: 100% checks08-23 uptime: 99.8% compliance: 100% checks08-24 uptime: 99.9% compliance: 100% checks08-25 uptime: 99.8% compliance: 100% checks08-26 uptime: 99.8% compliance: 100% checks08-27 uptime: 99.8% compliance: 100% checks08-28 uptime: 99.8% compliance: 100% checks08-29 uptime: 99.8% compliance: 100% checks08-30 uptime: 99.8% compliance: 100% checks08-31 uptime: 99.8% compliance: 100% checks09-01 uptime: 99.9% compliance: 100% checks09-02 uptime: 99.9% compliance: 100% checks09-03 uptime: 99.9% compliance: 100% checks09-04 uptime: 99.9% compliance: 100% checks09-05 uptime: 99.9% compliance: 100% checks09-06 uptime: 99.9% compliance: 100% checksuptimecompliance08-0909-06

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

PILLARS OVER TIME (measured)

Measured site and economics pillars from the assessment history, so the latest value shown elsewhere on this page reads as a point on a trend rather than a permanent state.

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

COMPLIANCE

13/13 checks pass · grade A

last 402 captured 2026-08-09 · last up 2026-09-06

  • 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 (18) live · click to expand
TIME STATUS RESP CAUSE
● OK 473ms
● OK 601ms
● OK 622ms
● OK 920ms
● OK 726ms
● OK 1089ms
● OK 861ms
● OK 644ms
● OK 462ms
● OK 698ms
● OK 767ms
● OK 756ms
● OK 877ms
● OK 800ms
● OK 620ms
● OK 685ms
● OK 817ms
● OK 521ms

EMBED THIS BADGE

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

Ask Cairn listed on x402-list
status
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</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) ]

To request delisting, email info@x402-list.com or update your listing at /services/ask-cairn/update.