Should your agent sign?

One POST before the signature: four paid questions to live Telegraph miners, one verdict, receipts anyone can verify.

Launch App API for agents
The Shield checkpoint An agent's proposed transaction passes through Shield, which runs four paid checks against live miners and returns sign when the score is 80 or more, or hold for CAUTION and BLOCK. AGENT about to sign proposed tx SHIELD 4 paid checks live miners · x402 score ≥ 80 score < 80 SIGN HOLD SAFE CAUTION · BLOCK
The checkpoint sits between "decided" and "signed". Verdicts are advisory.
$0.01per miner query · USDC over x402
4checks · one verdict
~10 sfull report · ~2–4 s per check
100%live miners · nothing mocked
How it works

From "about to sign" to evidence in four steps.

Every report is built fresh from paid miner answers at the moment you ask.

Four-step flow Describe the transaction, Shield queries live miners with one x402 payment of one cent per check, each text answer is graded pass, warn or fail, and a verdict with receipts comes back in about ten seconds. 1 Describe chain · to · value in ETH tx hash? · protocol? input 2 Query live miners x402 · $0.01 each · USDC GAS · TX · PRICE · TVL answers 3 Grade fixed public thresholds pass warn fail grades 4 Verdict + receipts SAFE · CAUTION · BLOCK miner · cost · ms · hash ~10 s end to end · ~2–4 s per paid check Four-step flow Describe the transaction, Shield queries live miners with one x402 payment of one cent per check, each text answer is graded pass, warn or fail, and a verdict with receipts comes back in about ten seconds. 1 Describe chain · to · value in ETH tx hash? · protocol? input 2 Query live miners x402 · $0.01 each · USDC GAS · TX · PRICE · TVL answers 3 Grade fixed public thresholds pass warn fail grades 4 Verdict + receipts SAFE · CAUTION · BLOCK miner · cost · ms · hash ~10 s end to end · ~2–4 s per check
Only the checks your input allows will run, and only those are paid for.
The four checks

Four questions. Four intents. Fixed thresholds.

Each check is one $0.01 query to a live miner, graded against published constants.

FEE

GAS_PRICE

Is gas sane right now?

warn · fee level high warn · > 10× chain floor
answered by Truvian · 8453 runs always

COUNTERPARTY

ONCHAIN_TX_LOOKUP

Did the referenced tx actually succeed?

fail · reverted warn · not found
answered by Truvian · 8453 runs with a tx hash

VALUE

CRYPTO_PRICE

How many dollars are at stake?

warn · > $10,000 fail · > $100,000 unless the tx hash verifies
answered by ChainSight · 302 runs with a value

LIQUIDITY

TVL_LOOKUP

Is the protocol still liquid?

warn · TVL < $1,000,000
answered by ChainSight · 302FinWire · 7322 runs with a protocol
Scoring

Start at 100. Lose points for what the miners find.

Same evidence, same verdict, every time.

Score scale A 0 to 100 scale: below 50 is BLOCK, 50 to 79 is CAUTION, 80 and above is SAFE. Every report starts at 100. start at 100 BLOCK < 50 CAUTION 50–79 SAFE ≥ 80 0 50 80 100 score = 100 − penalties Score scale A 0 to 100 scale: below 50 is BLOCK, 50 to 79 is CAUTION, 80 and above is SAFE. Every report starts at 100. start at 100 BLOCK CAUTION SAFE 0 50 80 100 score = 100 − penalties
≥ 80 SAFE · 50–79 CAUTION · < 50 BLOCK.

Penalties

−15 warn −35 fail −10 error

Overrides

any fail ⇒ at most CAUTION
two fails ⇒ BLOCK
Architecture · payment

One request in, one paid query per check, one hash back.

Every query is a real x402 settlement in USDC on Base Sepolia - gasless for the payer, onchain for everyone.

Shield architecture and payment flow An agent posts to the Shield API. For each check Shield pays the Telegraph engine over x402: an HTTP 402 challenge, an EIP-3009 authorization signed with viem, a PAYMENT-SIGNATURE header, and USDC settlement on Base Sepolia. The engine routes each intent to a live miner, Truvian 8453, ChainSight 302 or FinWire 7322, and returns the answer with a signal hash that flows back to the agent and can be resolved on the node. AGENT your code POST /api/check verdict receipts SHIELD API truvian.xyz pays · grades · scores paid query answer + signal_hash TELEGRAPH ENGINE devnode · Base Sepolia routes intents to miners issues signal_hash intent Truvian · 8453 GAS_PRICE · ONCHAIN_TX_LOOKUP ChainSight · 302 CRYPTO_PRICE · TVL_LOOKUP FinWire · 7322 TVL_LOOKUP live miners · $0.01 each x402 payment · per check · gasless settlement HTTP 402 challenge sign EIP-3009 with viem PAYMENT-SIGNATURE header settle USDC on Base Sepolia VERIFY ON NODE /engine/v1/signal/<hash> anyone Shield architecture and payment flow An agent posts to the Shield API. For each check Shield pays the Telegraph engine over x402: an HTTP 402 challenge, an EIP-3009 authorization signed with viem, a PAYMENT-SIGNATURE header, and USDC settlement on Base Sepolia. The engine routes each intent to a live miner, Truvian 8453, ChainSight 302 or FinWire 7322, and returns the answer with a signal hash that flows back to the agent and can be resolved on the node. AGENT your code POST /api/check SHIELD API truvian.xyz · pays · grades paid query x402 · per check · gasless 1HTTP 402 challenge 2sign EIP-3009 with viem 3PAYMENT-SIGNATURE header 4settle USDC on Base Sepolia TELEGRAPH ENGINE routes · issues signal_hash answer + signal_hash intent Truvian · 8453 GAS_PRICE · ONCHAIN_TX_LOOKUP ChainSight · 302 CRYPTO_PRICE · TVL_LOOKUP FinWire · 7322 TVL_LOOKUP VERIFY ON NODE /engine/v1/signal/<hash> anyone resolves the hash
request · payment answer · signal hash · verification
Shield never custodies your keys; it pays miners from its own USDC wallet and hands back the evidence.
Verifiability

Don't trust the card. Resolve the hash.

Every check carries a signal hash issued by the Telegraph node - anyone can fetch it.

miner latency cost signal_hash
A check receipt One check card shows the miner, latency, cost and a signal hash; the hash resolves on the Telegraph node at devnode.telegraphprotocol.com/engine/v1/signal. FEE GAS_PRICE pass gas within normal range minerTruvian · 8453 latency750 ms cost$0.01 · x402 signal_hash0x<64 hex> verify signal ↗ NODE confirms ✓ devnode.telegraphprotocol.com /engine/v1/signal/<hash>
The node, not Shield, is the source of truth for every answer.
For agents

One POST before you sign.

The dashboard and the API return the same report.

# pre-check a transfer before signing
curl -sS https://truvian.xyz/api/check \
  -H 'content-type: application/json' \
  -d '{"chain":"base","to":"0x4200000000000000000000000000000000000006","valueEth":"0.25","protocol":"aave"}'
# → {"verdict":"SAFE","score":100,"reasons":[],"checks":[…]}
BLOCK → stop CAUTION → escalate SAFE → sign
  • POST/api/check{chain, to?, valueEth?, txHash?, protocol?} → verdict, score, reasons, checks[]
  • GET/api/verify/:txHashone ONCHAIN_TX_LOOKUP verification · reverted ⇒ BLOCK
  • GET/api/stats{checksRun, telegraphRequests, byIntent}
  • GET/healthz{ok:true}
Why Truvian

We built the miner, the scorer and the app.

Shield does not just consume Telegraph. The same team supplies the answers, wrote the module that grades them, and pays for every one it uses.

Supply

The miner

Registration 172, live at miner.truvian.xyz, serving ONCHAIN_TX_LOOKUP and GAS_PRICE on Base. It counts the OP-stack L1 data fee that most implementations silently drop, and answers in about 0.8 seconds.

Quality

The scorer

An open WebAssembly module that grades miner answers on facts, not word overlap: exact values, addresses, status words, and negation. Promoted to network champion twice, registrations 544 and 617.

Demand

This app

Shield pays live miners in USDC for every check, and charges for its own, so the loop closes: supply, grading, and a paying customer, all on one protocol.

Full source, including the scorer and its test harness, is on GitHub.

FAQ

Four questions a judge would ask.

What does a check cost?

One miner query at $0.01 in USDC over x402 - a full four-check report is four cents.

Which chains?

base, ethereum and base-sepolia; miner payments always settle on Base Sepolia, where the live Telegraph deployment runs.

Is SAFE a guarantee?

No - verdicts are advisory; Shield surfaces live evidence and never custodies keys or signs.

Is anything mocked or cached?

No; every answer comes from a live miner at request time, and an unreachable miner is graded error, never filled in.

Try it

Run a check against live miners now.

Four cents, ten seconds, receipts included.

Launch App Source ↗