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What is
Note (Bearer Instrument)?
A programmable IOU on Ergo — a UTxO encoding a payment obligation that can be transferred between agents and redeemed against a Reserve.
In Ergo's agent economy stack, a Note is a bearer instrument implemented as a UTxO box. It references a Reserve box (the collateral backing), contains a value in ERG or tokens, an expiry block height, and an optional acceptance predicate. Notes can be transferred between agents without any issuer involvement — whoever holds the Note can redeem it against the Reserve. The acceptance predicate encodes conditions that must be true at redemption time, enabling trustless payment-for-task flows without off-chain oracles. ChainCash is the production implementation of the Note protocol on Ergo mainnet.
Key Points
- A Note is a UTxO box, not a token — it uses ErgoScript as spending logic
- References a Reserve box as its backing collateral
- Contains: value, expiry height, optional acceptance predicate, reserve box ID
- Transferable between agents without issuer involvement
- Redeemed against Reserve — Tracker prevents double-redemption
- Acceptance predicate: conditions that must be satisfied at redemption
Use Cases
1
Agent payment for API call with task hash acceptance predicate
2
Community currency note backed by shared ERG Reserve
3
Sub-agent credit issued by orchestrator within credit limit
4
Deferred payment: Note issued now, redeemed after task completion
Technical Details
A Note box in Ergo typically uses registers: R4 = reserve box ID (to verify collateral), R5 = expiry block height, R6 = acceptance predicate hash or inline script. The spending script verifies HEIGHT < R5, that the redemption transaction includes the correct Reserve box, and that any acceptance conditions are satisfied. The Tracker box is also included in the redemption transaction to prevent double-spend.
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Questions about Note (Bearer Instrument)
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Is Ergo a good investment?
This is not financial advice. Ergo has strong fundamentals: fair launch (no VC dump risk), innovative technology (eUTXO, Sigma Protocols, NiPoPoWs), active development, and a cypherpunk ethos. It's a smaller market cap project with higher risk/reward than established chains. Research thoroughly, understand the technology, and never invest more than you can afford to lose.
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Getting Started
How to get started with Ergo?
Start by getting a wallet (Nautilus for browser, Terminus for mobile). Back up your seed phrase securely offline. Get some ERG from an exchange (Gate.io, KuCoin) or DEX (Spectrum). Make a test transaction. Then explore: try DeFi on Spectrum, check out NFTs, or dive into the technology if you're a builder.
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Getting Started
How to use Spectrum DEX on Ergo?
Connect your Nautilus wallet to Spectrum Finance, select tokens to swap, review the rate and slippage, then confirm. Spectrum uses AMM liquidity pools for instant trades. You can also provide liquidity to earn fees. All trades are atomic - they complete fully or not at all, with no front-running possible.
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DeFi
What are NiPoPoWs and why do they matter?
NiPoPoWs (Non-Interactive Proofs of Proof-of-Work) are cryptographic proofs that compress blockchain history. Instead of downloading gigabytes of blocks, light clients can verify the chain with just kilobytes of data. This enables true trustless light wallets, efficient cross-chain bridges, and sidechains - all without trusting third parties.
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