Oblique Paid Endpoints

Buying from oblique.markets paid endpoints

Every route under https://api.oblique.markets/api/v1/paid/* answers an unpaid request with HTTP 402 and a machine-readable quote. You pay the quoted amount, retry the same request with a payment header, and get JSON. There are no accounts and no API keys; the payment is the authentication. Two rails are offered on the same 402 (dual-stack):

Prices are per call, quoted in USD and settled in stablecoin atomic units (6 decimals: "2000" = $0.002). On 2026-09-09 the catalogue advertised 77 paid routes from $0.001079 to $1.00; most cost $0.002–$0.05. Use an SDK for production buying; the bundled scripts/buy.py shows the whole loop in ~150 lines if you want to see exactly what an SDK signs.

Discovery surfaces (all free, no auth)

scripts/catalog.py                  # today's catalogue as a Markdown table, no wallet
scripts/catalog.py --grep solana    # only matching routes
scripts/catalog.py --json           # machine-readable

Step 1 — read the quote (free)

curl -si https://api.oblique.markets/api/v1/paid/bazaar-pulse
scripts/quote.sh bazaar-pulse       # same, decoded: x402 accepts, MPP terms, input shape, output example

The 402 carries the quote three ways at once:

• PAYMENT-REQUIRED header — base64 of the x402 v2 PaymentRequired JSON.
• JSON body — the same object, readable: {"x402Version":2,"accepts":[{"scheme":"exact","network":"eip155:8453","amount":"2000","payTo":"0x9700…D3Ab","asset":"0x8335…2913","maxTimeoutSeconds":60,…},{"network":"solana:5eykt4…","amount":"2000","payTo":"GYyT…ykdS","asset":"EPjF…Dt1v",…}],"extensions":{"bazaar":{"info":{"input":…,"output":{"example":…}}}}}. extensions.bazaar.info tells you the input shape and shows an example output before you pay — read it.
• WWW-Authenticate: Payment id="…", realm="api.oblique.markets", method="tempo", intent="charge", request="<base64url>", expires="…" — the MPP challenge. request decodes to {"amount":"2000","currency":"0x20c0…0000","methodDetails":{"chainId":4217,"supportedModes":["pull"]},"recipient":"0xD96A…3D6d"}.

x-payment-amount: $0.002 is also set as a convenience. The challenge is authoritative: take amount, payTo, asset, network from it, never from memory.

Step 2 — pay and retry

Quickest: the bundled buyer (Base USDC, no SDK)

scripts/buy.py is a complete x402 exact buyer in plain Python (requests + eth-account). It reads the 402, refuses any quote above your ceiling, signs an EIP-3009 transferWithAuthorization for exactly the quoted amount, retries with PAYMENT-SIGNATURE, and prints the result and the decoded settlement receipt (transaction hash included).

pip install requests==2.32.5 eth-account==0.13.7
printf '%s' '0xYOUR_PRIVATE_KEY' > ./buyer.key       # a dedicated wallet with a little USDC on Base
scripts/buy.py bazaar-pulse --key-file ./buyer.key                       # $0.002
scripts/buy.py 'base-usdc-balance?address=0x970007590aCC5C938cd51345B17AF51B1B40D3Ab' --key-file ./buyer.key
scripts/buy.py web-extract --post '{"url":"https://example.com"}' --max-usd 0.05 --key-file ./buyer.key
scripts/buy.py bazaar-pulse --quote-only                                 # no key: print the quote

The key is read from the file named by --key-file and nowhere else. --max-usd defaults to 0.01, so a mispriced or unexpected quote exits 3 without signing. Exit 0 is a settled purchase; 4 means the facilitator rejected the payment; 5 means the route rejected your input after payment, which settles nothing.

x402 SDKs (Base or Solana USDC)

The v2 SDKs read the 402, pick a network you configured, sign the USDC authorization, and retry with PAYMENT-SIGNATURE. Working files in oblique-markets/oblique-examples:

All four take the private key of a Base wallet holding a little USDC and set an explicit per-payment ceiling so a mispriced challenge fails instead of spending. Use a dedicated, thinly funded wallet. Note the SDK generation: x402 v2 (@x402/fetch 2.x, x402 2.x on PyPI, CAIP-2 network ids, PAYMENT-REQUIRED/PAYMENT-RESPONSE headers). The v1 packages (x402-fetch 1.x, X-PAYMENT header) are deprecated and will not match.

Python sketch (pip install x402[requests,evm]==2.22.0; mirrors pay_for_time.py):

from eth_account import Account
from x402 import SchemeRegistration, prefer_network, x402ClientConfig, x402ClientSync
from x402.http.clients.requests import x402_requests
from x402.mechanisms.evm.exact import ExactEvmScheme
from x402.mechanisms.evm.signers import EthAccountSigner

with open("buyer.key") as f:                                  # dedicated wallet, a little USDC on Base
    signer = EthAccountSigner(Account.from_key(f.read().strip()))
config = x402ClientConfig(
    schemes=[SchemeRegistration(network="eip155:*", client=ExactEvmScheme(signer=signer))],
    spend_controls={"max_amount_per_payment": "$0.05"},   # ceiling: a mispriced quote fails, not spends
    policies=[prefer_network("eip155:8453")],             # Base; register x402.mechanisms.svm.exact for Solana
)
session = x402_requests(x402ClientSync.from_config(config))  # requests.Session: 402 → sign → retry
route = "https://api.oblique.markets/api/v1/paid/base-gas-price"
r = session.get(route, timeout=30)
r.raise_for_status()
print(r.json(), r.headers.get("PAYMENT-RESPONSE"))            # JSON result + base64 settlement receipt

MPP / Tempo

The MPP credential is Authorization: Payment <base64url JSON> where the JSON is {"challenge":{…echoed WWW-Authenticate params…},"payload":{…tempo-specific signed transfer…}} (spec: https://paymentauth.org/draft-httpauth-payment-00.txt, §5.2). The mppx client builds it for you (npm install mppx@0.9.2 viem@2.56.3):

import { privateKeyToAccount } from 'viem/accounts'
import { Mppx, tempo } from 'mppx/client'
Mppx.create({ methods: [tempo({ account: privateKeyToAccount(buyerKey) })] })   // buyerKey: read from your key file
// installs a payment-aware fetch: 402 → sign Tempo charge → retry with Authorization: Payment
const route = 'https://api.oblique.markets/api/v1/paid/bazaar-pulse'
const r = await fetch(route)

A successful MPP response carries Payment-Receipt (base64url JSON). Docs: https://mpp.dev (Tempo charge: /payment-methods/tempo/charge).

Step 3 — read the result

200 with application/json. Shapes are in openapi.json and in the challenge's extensions.bazaar.info.output.example. Payment failures come back as a fresh 402 (x402 puts the reason in the body error; MPP uses RFC 9457 problem details). A 4xx other than 402 with a valid payment means the input was rejected (check the schema) — no charge is settled. PAYMENT-RESPONSE decodes to {"success":true,"transaction":"0x…","network":"eip155:8453","payer":"0x…"}; the transaction is the on-chain USDC transfer you can verify yourself.

When to use which cheap route

Prices from the live catalogue on 2026-09-09. GET routes take query params; POST routes take JSON bodies. Every one is also a paid MCP tool (bazaar_pulse, base_gas_price, …).

Other frequently useful routes: time / echo ($0.01, the smallest end-to-end payment test), crypto-price ($0.004), token-metrics ($0.003), x402-endpoint-verify ($0.02, lint someone else's 402), settlement-verify ($0.01, prove a Base USDC settlement landed), inference (LLM proxy; $1.00 maximum on Base under the upto scheme, $0.01 fixed on Solana; models at the free GET /api/v1/models). The full list with prices is in references/catalog.md; scripts/catalog.py prints today's.

Rules of thumb

• Fetch the quote first (free) and compare amount against your ceiling before paying.
• Snapshot-based Bazaar routes update once a day; do not re-buy the same day expecting change.
• Prefer Base for exact payments (both facilitators cover it); Solana needs the fee-payer the challenge names in extra.feePayer.
• scripts/quote.sh <route> prints the decoded quote for any route without paying; scripts/buy.py <route> --quote-only does the same from Python.
• The free observatory at https://remote.observer (see the remote-observer skill) already answers the daily Bazaar diff and provider ranking at no cost — pay here for the fuller paid variants (bazaar-trending, bazaar-seller-rank, bazaar-market-report, …) or for non-market routes.