APIs for
AI agents
on Base
in USDC
nsgoods
nsgoods is a suite of eight x402 pay-per-call APIs for AI agents on Base + Solana — signed, provable, with a free preview on every service.
● 8 services · live on Base + Solana
Eight oracles.
One cup each.
| GET /backtest | $0.25 |
| GET /signals/top | $0.10 |
| GET /history | $0.05 |
| GET /regime/changed | $0.02 |
| GET /signals?pair=BTC/USD | $0.01 |
| GET /indicators | $0.005 |
| GET /signals/preview | FREE |
curl https://signals.nsgoods.org/signals/preview
→ {"pair":"BTC/USD","signal":"…","signed_by":"0x…"}
| GET /agent-trust?agent=<id>&chain=<name> | $0.005 |
| GET /agent-trust/preview | FREE |
curl https://trust.nsgoods.org/agent-trust/preview
→ {"agent":…,"score":…,"components":{…},"signed_by":"0x…"}
| GET /regime?id=1 (1=BTC · 1027=ETH · 1839=BNB) | $0.01 |
| GET /provable/head | FREE |
curl https://regime.nsgoods.org/provable/head
→ {"count":1887,"head":{"regime":"RISK_OFF",…}}
| GET /solar-legality?state=<state> | $0.005 |
| GET /solar-legality/all | $0.02 |
| GET /solar-legality/preview | FREE |
curl "https://solar.nsgoods.org/solar-legality/preview?state=california"
→ {"state":"california","legal_status":"…"}
| GET /screen?address=<addr>&chain=<base|ethereum|bsc|polygon|mantle|solana> | $0.005 |
| GET /screen/preview?address=<addr>&chain=<name> | FREE |
curl "https://trust.nsgoods.org/screen/preview?address=0x…&chain=base"
→ {"malicious":…,"sanctioned":…,"hard_flags":[…],"soft_flags":[…],"sources":[…],"screening_verdict":"…","signed_by":"0x…"}
OFAC sanctions — Chainalysis on-chain oracle (EVM) malicious-address — GoPlus (EVM + Solana)
| GET /screen?address=<addr>&chain=<chain> | $0.005 |
| GET /screen/preview | FREE |
Solana mainnet · USDC (SPL) · gasless (facilitator feePayer) payTo 35tCuyL3E7M88jfhTeEaRxhrbuKFyQLWgxJQyf5QcLLe
curl "https://sanctions.nsgoods.org/screen/preview"
→ {"preview":true,"demo_address":"0x19aa…4dff","input_ignored":false,"sanctioned":true,"matched_label":"ETH","verdict":"deny","sdn_snapshot_at":"…","signed_by":"0x57fF…"}
OFAC SDN exact-address match, 20 chains (XBT 527, TRX 198, ETH 100, USDT 93, SOL 4, …) Negative-evidence only — deny, or "no SDN match" (≠ safe). No heuristic/GoPlus layer.
Verifying the signature on /screen/preview. The preview response adds four fields after signing: preview, demo_address, input_ignored, note. Strip all four, plus signature and signed_by, before you verify. The paid /screen response adds nothing after signing, so there you strip only signature and signed_by.
| GET /payable?resource=<https-url> | $0.005 |
| GET /payable/preview | FREE |
Base (USDC, payTo 0xc87a06…5EF990) or Solana (USDC-SPL, payTo 35tCuyL3…) — Base first
curl "https://payable.nsgoods.org/payable/preview"
→ {"schema_version":2,"verdict":"PAYABLE","payable_networks":["solana:5eykt…"],"options":[{"network":"solana:5eykt…","verdict":"PAYABLE","detail":{"ata_exists":true,"token_program":"spl"}}],"preview":true,"demo_resource":"https://sanctions.nsgoods.org/screen","signed_by":"0x41Fb…"}
Reachable + well-formed 402 + (Solana) destination-ATA existence. Derive ATA = find_program_address([payTo, tokenProgram, mint], ATokenGP…); ≤3 RPC calls. Every response signed.
Recover the signer over the canonical JSON with signature + signed_by removed; recover == signed_by. On /payable/preview strip the four post-sign fields first (preview, demo_resource, input_ignored, note).
Free on every service: /health · preview · /provable/head · /provable/verify · /.well-known/x402 · /openapi.json · /llms.txt
No accounts.
No API keys.
An agent calls a paid endpoint. Plain HTTP — nothing to sign up for.
It receives HTTP 402 Payment Required with the price and payment instructions.
It pays USDC on Base and retries. The data comes back — signed.
Trust nothing.
Verify everything.
Verifiable delivery
Every paid call to nsgoods data services (extractability, agent-trust, regime, solar) returns a signed proof of delivery: a tamper-proof Ed25519 receipt any agent can verify independently. Verify at /proof/pubkey on each service.
- ECDSA-signed responses — recover the signer, prove authenticity.
- Public hash-chain proofs — tamper-evident history for every service.
- Free preview on every service — try before paying a cent.
- Machine-discoverable — manifests, OpenAPI, llms.txt. MCP-ready.
- Just HTTP and USDC on Base — nothing else between the agent and the data.
One command in Claude Desktop or Cursor exposes the nsgoods oracles as MCP tools. Every preview is free; paid tools need EVM_PRIVATE_KEY — a low-balance Base wallet (USDC).
Independent trust- and compliance-scores by x402.fuchss.app · updates daily·See all endpoints scored →
Monitored by x402-list.com · measured uptime, updated live
Money-back
guarantee
Testnet proven · Base Sepolia
We built and publicly proved an on-chain escrow-bond guarantee for x402 calls. If a paid service fails to deliver, the buyer is compensated from the seller's USDC bond — enforced by a smart contract, triggered by a signed delivery verdict. Proven end-to-end on Base Sepolia. Mainnet next.
Seller posts a bond — USDC locked in a contract.
Verifier signs the delivery verdict — DELIVERED or FAILED.
FAILED → buyer is paid from the bond — automatic, on-chain.
Built by Nikolaos Dimitriadis — indie dev building for the agent economy. Liverpool, UK.
X @nickbuildsai · LinkedIn