Claros

Claros is a verifiable real-world-data oracle on Casper. An autonomous agent reads trusted public sources (U.S. energy data from the EIA, plus civic feeds such as San Diego parking revenue), attests each value on-chain together with its provenance, and exposes it as a self-describing feed that any app, backend, or contract can read by a single feed_id.

If you have used Pyth , Claros will feel familiar. Values live on-chain as integers, every feed describes its own decimals and unit, and a reading is amount / 10^decimals. Casper is the settlement layer, your feed_id is the key, and there is no indexer to run.

What problem it solves

Smart contracts cannot call an HTTP API, and most real-world data (energy prices, generation, emissions, municipal revenue) lives behind public web APIs that contracts and other agents cannot trust directly. Even when an app fetches that data off-chain, there is no shared, tamper-evident record of what value was true at a given time.

Claros closes that gap:

• One canonical value on-chain. Each feed has exactly one latest attested value, written to a Casper contract by a known attester.
• Provenance you can verify. Every attestation carries the reporting period, a source_hash of the upstream payload, the attester address, and a timestamp.
• A self-describing schema. A feed publishes its own decimals, unit, source, route, and frequency, so consumers never hardcode scaling factors.
• Many ways in. Read the same value from a frontend, a backend in any language, another Casper contract, or a paid pay-per-call endpoint.

The model: self-describing feeds, the Pyth way

A reading is split across two contracts, joined by the feed_id:

The on-chain amount is always an unsigned integer (U512). To get the human number you divide by 10^decimals, exactly like Pyth’s price x 10^expo:

// EIA.PET.PRICE.WTI.DAILY  (WTI crude oil spot price)
amount   = 78940000n            // integer, from AttestationRegistry
decimals = 6                    // from FeedRegistry
value    = 78940000 / 10 ** 6   // 78.94  ($/bbl)

Pairing the value with its self-describing metadata is the heart of the design. See How it works for the full attestation pipeline and the two-registry layout, and Decimals and scaling for the exact integer math.

How a reading is made

The agent runs as an hourly heartbeat that acts only on new data. Each cycle also anomaly-checks the reading and makes a treasury decision, recorded on-chain through the TreasuryVault, so Claros is an oracle and an autonomous on-chain participant at once. See How it works for the full agent cycle.

What data Claros has

Claros currently serves 38 feeds live on-chain: the EIA energy series, the civic San Diego parking feed (OP-1), and an operator-claimed solar feed (EIA.ELEC.GEN_SUN.US48.HOURLY, attested by an independent operator). Those feeds are mapped from a crawled catalog of 232 EIA datasets, and so far 78+ attestations have been written.

The energy feeds span every major EIA family: petroleum, natural gas, electricity, coal, nuclear, densified biomass, total and state energy (SEDS), CO2 emissions, short-term outlooks, and international energy. A few examples:

Recent values include WTI at $78.94/bbl and Henry Hub at $3.16/MMBtu. The flagship civic feed OP-1 (San Diego parking revenue) read $2,734.20 for the period 2026-06-23.

The EIA APIv2 is one uniform faceted API, and a feed_id pins down a single series within it: a route (for example petroleum/pri/spt), one frequency, a data column, and a set of facet filters (for example series, duoarea, stateid, or fueltype). That mapping is covered in the data model. Beyond the 36 live energy feeds, any dataset in the catalog can be registered and attested on demand.

Four ways to read it

The same on-chain value is reachable four ways. Pick by where your code runs and whether you want a free read or metered, paid access. See Choose a method for a side-by-side comparison.

The off-chain methods return the same reading. Here is a single feed in each:

curl http://localhost:4030/v1/feeds/EIA.PET.PRICE.WTI.DAILY
# {
#   "feed_id": "EIA.PET.PRICE.WTI.DAILY",
#   "value": 78.94, "amount": "78940000", "decimals": 6,
#   "unit": "$/bbl", "title": "WTI crude spot", "source": "EIA",
#   "period": 20260623, "source_hash": "…", "updated_at": 1750636800000
# }

import { ClarosOracle } from 'claros-oracle';
 
const claros = new ClarosOracle(); // testnet defaults
const wti = await claros.getReading('EIA.PET.PRICE.WTI.DAILY');
// { feed_id, value: 78.94, unit: '$/bbl', decimals: 6, amount: 78940000n, ... }

let v = AttestationRegistryRef::new(env, registry).get_latest(feed_id.clone()); // value
let m = FeedRegistryRef::new(env, feed_registry).get_feed(feed_id);             // decimals/unit
// real value = v.amount / 10^m.decimals

The x402 metered endpoint wraps a feed behind the HTTP 402 payment protocol: a first request returns 402 Payment Required, the client signs a WCSPR payment and retries with an X-PAYMENT header, a facilitator settles it on Casper, and the response carries the reading plus its on-chain provenance. That metered path is how the Claros agent funds its own attestations.

Network and contracts

Everything is live on the Casper testnet (network casper-test), reachable at the public RPC https://node.testnet.casper.network/rpc and viewable on the explorer at https://testnet.cspr.live. The four Claros contracts are upgradable and keyed by package hash:

Where to go next