Abstract
Agentic AI systems composed of multiple large-language-model (LLM) agents need verifiable agent identity, tamper-evident records of completed work, and machine-to-machine settlement. Existing agent-economy designs concentrate on registration, discovery and reputation, while consortium-chain notarisation services anchor document hashes on chains whose membership is restricted to known institutions. We present AgentLedger, a smart contract deployed on SCDO Shard0, an EVM-compatible proof-of-work (PoW) shard, which records agent registration, Merkle roots of batches of signed task messages, and pay-per-task receipts. Seven AI agents, each bound to one externally owned account, keep task artefacts off-chain, sign EIP-712 messages carrying the SHA-256 digest of each result, and settle tasks through a direct-forwarding payment call. In an initial deployment (one afternoon, 16 contract transactions), anchoring a seven-message batch cost 167,486 gas, a payment about 36,384 gas, and the median time to a receipt was 9.0 s. We further describe the design of a zero-reward, zero-gas PoW coordination chain that is to checkpoint its state to SCDO Shard0, and we compare public-PoW anchoring with consortium hash anchoring as offered by AntChain. The hybrid design offers permissionless auditability at the cost of the probabilistic finality inherited from the PoW host chain.
摘要
由多個大型語言模型（LLM）代理組成的代理式 AI 系統，需要可驗證的代理身份、防竄改的已完成工作紀錄，以及機器對機器的結算。現有的代理經濟設計集中於註冊、發現與信譽，而聯盟鏈存證服務則把文件雜湊錨定在成員僅限已知機構的鏈上。本文提出 AgentLedger，這是一個部署於 SCDO Shard0（相容 EVM 的工作量證明（PoW）分片）的智能合約，記錄代理註冊、已簽名任務訊息批次的 Merkle 根，以及按任務付款的收據。七個 AI 代理各綁定一個外部擁有帳戶，將任務產物保存在鏈下，簽署載有每個結果 SHA-256 摘要的 EIP-712 訊息，並透過直接轉發的支付呼叫結算任務。在初期部署中（一個下午、16 筆合約交易），錨定一個含七則訊息的批次耗用 167,486 gas，一次支付約 36,384 gas，取得收據的中位時間為 9.0 秒。本文進一步描述一條零獎勵、零 gas 的 PoW 協調鏈的設計，該鏈將把其狀態檢查點寫入 SCDO Shard0；並比較公有 PoW 錨定與螞蟻鏈（AntChain）所提供的聯盟鏈雜湊錨定。此混合設計提供無須許可的可稽核性，代價是繼承自 PoW 宿主鏈的機率性最終確定性。
Live-chain test
On 2026-10-05 the full end-to-end flow ran on SCDO Shard0 (chainId 5680) in 58 seconds, using the code merged at commit 2c945a6. The four transactions are public on the explorer:
- registerAgent:
0x8bdf6badb4…3c954d8e - anchorRoot:
0x73808b87e8…14191f0c - payout workerA:
0xd0989cd136…eb5d4167 - payout workerB:
0x841534aa41…6f3de0a3
Running settlement a second time made no duplicate payment (idempotent).
真鏈實測
2026 年 10 月 5 日，在 SCDO Shard0（chainId 5680）上完成完整端到端流程，耗時 58 秒，程式碼合併於 commit 2c945a6。四筆交易均可在瀏覽器公開查看：
- registerAgent：
0x8bdf6badb4…3c954d8e - anchorRoot：
0x73808b87e8…14191f0c - 支付 workerA：
0xd0989cd136…eb5d4167 - 支付 workerB：
0x841534aa41…6f3de0a3
重複結算不會重複付款（冪等）。
引用本文Cite this paper
BibTeX
@misc{zhang2026agentledger,
author = {Zhang, Ying Willam},
title = {{SCDO Agent Ledger}: On-Chain Identity, Work Attestation and Settlement for Autonomous {AI} Agents on a Sharded {PoW} Blockchain},
year = {2026},
month = oct,
publisher = {Zenodo},
howpublished = {Preprint},
doi = {10.5281/zenodo.23209794},
url = {https://doi.org/10.5281/zenodo.23209794},
note = {SCDO Laboratory, 9Y9 PTY LTD. Open access, CC BY 4.0}
}