L2 Agent Economics · AI Agent Workload Comparison of Arbitrum vs Base vs Optimism

TL;DR

For AI agent workloads in 2026 年, L2 selection is converging on Base as the default, while Arbitrum + Optimism each capture some niches (Arbitrum for DeFi-heavy agents + institutions, Optimism for the OP Stack ecosystem + public goods). The per-transaction costs of the 3 L2 s, after Pectra EIP-7691 · blob doubling and the L2 economic chain, all fall into the $0.001-0.01 range, but Base has the full-stack default of Coinbase CDP + USDC Native + Coinbase Smart Wallet + ERC-4337 paymaster, almost automatically steering agent developers’ “L2 selection” decision toward Base. Arbitrum’s edge is deeper DeFi liquidity (GMX / Camelot / Pendle)+ Stylus (WASM)+ Orbit RaaS as a path for institutional agents to build their own chains. Optimism’s edge is the Superchain network effect (World, Zora, Worldcoin)+ retroactive funding, but its share in agent-payment scenarios is the smallest. Sequencer MEV is still extracted by centralized sequencers on all 3 chains, making it a potential risk for high-frequency agent payments.

Wiki route

This entry sits under systems index. Read it against ERC-4337 overview and ERC-4337 wallet adoption to understand the wallet layer for agent transactions, and against agent economy index to see the evolution of the full agent-payment protocol stack. For the economic background of per-transaction costs, see Pectra EIP-7691 blob expansion.

3 L2 basic parameter comparison (2026-Q1)

Perspective	Base	Arbitrum One	Optimism Mainnet
Type	OP Stack (Bedrock + Fault Proof)	Arbitrum Nitro (custom rollup)	OP Stack (Bedrock + Fault Proof)
TVL (DefiLlama, 2026-Q1)	~$8-10B	~$15-20B	~$1-2B
Daily tx	~3-5M	~2-3M	~300-500k
Average per-tx user fee (post-Pectra)	$0.001-0.005	$0.002-0.01	$0.001-0.005
DA layer	Ethereum blob	Ethereum blob (Nova partly uses AnyTrust DA)	Ethereum blob
Sequencer centralization	Coinbase single sequencer	Offchain Labs single sequencer (BoLD fault proof + decentralization plan)	Optimism Foundation single sequencer (decentralization plan)
Native USDC	USDC Native (Circle, 2023-09 launch)	USDC Native (2023-06 launch)	USDC Native (2023-09 launch)
Bridged USDC	USDbC (deprecated, user migration mostly complete)	USDC.e (legacy, still exists)	USDC.e (legacy, still exists)
Smart wallet default	Coinbase Smart Wallet (ERC-4337)	Multiple third parties (Safe / Biconomy, etc.)	Multiple third parties
Paymaster commercial product	Coinbase CDP Paymaster	Alchemy Account Kit / Biconomy / Pimlico	Alchemy Account Kit / Biconomy / Pimlico
Known large agent / payment integrations	x402 / Coinbase Agent Kit / Privy default	GMX agent / DeFi agent / some institutions	World mini-apps / Worldcoin

Per-transaction cost · agent workload perspective

Typical AI agent workloads:

micropayment (per 1 API call charged at $0.001-0.10 ): per-tx cost must be below $0.005 ; Base/Optimism satisfy this, while Arbitrum is on the boundary
periodic settlement (daily / hourly batching of many small settlements): with batch contracts + bundled UserOp (ERC-4337), per-call is distributed to the $0.0005 order; all 3 chains can do it
DeFi-action agent (swap / lend / stake): per-tx $0.01-0.10, acceptable on all 3 chains, with Arbitrum advantaged by DeFi depth
bridge-action agent (cross-chain asset funding): per-bridge $0.20-2.00 (including CCTP V2 burn-mint + L1 finality + target-chain mint), expensive but low-frequency

Post-Pectra data: EIP-7691 raised the Ethereum blob target from 3 to 6 per block + max 9, directly reducing L2 calldata cost to 2023 年’s 1/3-1/5 . See Pectra EIP-7691 · blob doubling and the L2 economic chain for details.

Sequencer MEV implications for agents

All 3 chains are still single centralized sequencers, directly affecting agents as follows:

front-running risk: High-value swap / arbitrage agents can be subject to sequencer reordering inside the mempool time window; none of Base / Arbitrum / Optimism has mandatory FCFS or fair ordering
time-boost auction (Arbitrum, 2024-04 launch): users can pay to cut in line, effectively institutionalizing MEV-via-priority; searchers can bid for priority inclusion, and moderately sensitive agents need to budget for time-boost costs
Base private mempool: Coinbase provided an optional private bundle route for Smart Wallet customers in 2024-2025 , partly mitigating sandwich attacks
Optimism Superchain shared sequencer roadmap: In theory, OP Stack chains can introduce cross-chain atomic execution by sharing a sequencer; not deployed in production as of 2026 年
decentralized sequencer: included in the roadmaps of all 3 chains, but as of 2026 年 none has meaningful mainnet progress; centralized sequencers remain a trust assumption agents must accept
agent practical advice: For high-value swaps, use chain abstraction patterns and route transactions through batch-auction paths such as Cowswap / 1inch / Skip, avoiding a sequencer single point of failure

Gas sponsorship / Paymaster availability

ERC-4337 paymaster allows dApp / agent platforms to pay gas on behalf of users, removing the biggest UX obstacle of “needing ETH.” Comparison of 3 chains:

Base + Coinbase CDP Paymaster

Product: Coinbase CDP Paymaster
Pricing: gas sponsorship + Coinbase fee markup, with daily / per-user caps configurable
Integration depth: Natively bound to Coinbase Smart Wallet, completing SCA creation + the first sponsored tx in 1 step
Agent friendliness: Coinbase Agent Kit + AgentKit SDK uses CDP by default, almost zero friction
Constraints: Coinbase risk controls + KYC data belong to Coinbase; agents are restricted in some jurisdictions

Arbitrum + Alchemy / Pimlico / Biconomy

Products: Alchemy Account Kit, Pimlico, Biconomy, Stackup all support Arbitrum
Mechanism: Third-party paymaster service, charged according to sponsored gas volume, usually with 5-15% markup
Integration: Requires self-integration on the dApp side; there is no “default full-stack” experience
Institution-friendly: Alchemy Account Kit provides SOC2 + enterprise SLA for institutional devs

Optimism + third parties similar to Arbitrum

Almost the same paymaster choices as Arbitrum, but the agent ecosystem is smaller and there are fewer concrete SDK integration cases

Paymaster strategy comparison

Perspective	Base / CDP	Arbitrum / Alchemy family	Optimism / same
Default bound wallet	Coinbase Smart Wallet	Safe / Biconomy SCA	Safe / Biconomy SCA
Onboarding friction	Extremely low (Coinbase account = SCA)	Medium (wallet + paymaster selection required)	Medium
Sponsor markup	Built into Coinbase	5-15% third-party markup	5-15%
Agent SDK default	Coinbase Agent Kit + Privy AgentCore default	Each SDK	Each SDK
Regulation / KYC	Coinbase aggregation	Custom per paymaster	Custom per paymaster

Native stablecoin liquidity · USDC Native vs Bridged

USDC Native (direct Circle issuance) vs USDC.e / USDbC (legacy bridges through Wormhole / OFT, etc.):

Base: USDC Native launched in 2023-09 , USDbC migration is mostly complete, and Base USDC circulation is ~$3-5B (2026-Q1)
Arbitrum: USDC Native launched in 2023-06 , but USDC.e legacy still has ~$500M-1B unmigrated (because of deep DeFi integrations), and total USDC is ~$3-4B
Optimism: USDC Native launched in 2023-09 , USDC.e legacy is ~$200-400M, and total USDC is ~$500-800M
CCTP V2 integration: Circle CCTP V2 burn-mint protocol has been deployed on all 3 chains; cross-L2 USDC transfer has 1-3 second finality + ~$0.01-0.10 fee
Impact on agents: Agent stablecoin holding / settlement should use USDC Native (avoiding secondary depeg risk from legacy bridges); Base’s USDC liquidity + default SCA + CDP make Base the default stablecoin rail for agents

PYUSD / USDT0 / RLUSD are deployed on 3 chains, but are far smaller than USDC; stablecoin payment in 2026 年 is effectively synonymous with USDC payment.

Developer defaults · Coinbase CDP / Privy / AWS AgentCore

Agent developers’ L2 selection is pre-locked by wallet providers + cloud SDKs:

Coinbase CDP: Base + USDC Native + Smart Wallet + Paymaster are the defaults; integration is a one-line implementation path, and agent settlement effectively defaults to Base
Privy + AWS AgentCore: Privy creates Base + Ethereum + Solana wallets by default in AWS Bedrock AgentCore integration; the default for agent payment is USDC on Base
x402 edge integration: x402 implementations by CDN/edge platforms such as Cloudflare / AWS / Vercel default to USDC on Base; the agent automatically chooses Base settlement through HTTP 402
Alchemy Account Kit: Multi-chain support, but GTM prioritizes Arbitrum + Base + Optimism + Polygon and recommends multi-chain for agents
Result: In 2025-2026, ~70%+ of new agent projects select Base as the settlement chain, while Arbitrum / Optimism / Polygon combined are ~30%; see embedded wallet network-effect moat for details

Arbitrum differentiation: DeFi depth + Orbit + Stylus

DeFi liquidity: GMX (perps)+ Camelot + Pendle + Radiant + Vertex; DeFi-heavy agents (yield optimizer / perps trader / collateral manager) get the deepest liquidity on Arbitrum
Orbit RaaS: Arbitrum Orbit gives enterprises / institutions / large DeFi protocols the option to build their own L3 ; Xai (gaming), Sanko, Cheese Chain, and others are live
Stylus: WASM-based contract execution; Rust / C / C++ contracts can interoperate with EVM; 2024-04 mainnet; theoretically advantageous for high-performance agent compute, but actual adoption is slow
Institutional customers: Some PayPal PYUSD on Arbitrum + some institutional Treasury deployments
Conclusion: Arbitrum remains the first-choice agent option for “DeFi depth demand + L3 RaaS + Stylus performance”

Optimism differentiation: Superchain + RetroPGF

Superchain: Base, World, Zora, Worldcoin, Mode, Lyra, Polynomial, and others share OP Stack codebase + governance + future sequencer
RetroPGF (Retroactive Public Goods Funding): Periodically distributes OP tokens to public-goods contributors; over 5 rounds, ~$300M+ has been distributed
agent scenario: World mini-apps (inside Worldcoin) are the largest real agent / mini-app deployment scenario, but diverge from the conventional ERC-4337 agent route
Constraints: Optimism Mainnet’s own TVL and daily tx are far below Base / Arbitrum, and its direct agent deployment share is the smallest

Bundled UserOp + Batched settlement · actual agent cost

The actual per-action cost for agents is not “1 UserOp 1 settlement”; rather, the bundler aggregates N UserOps to send them to EntryPoint:

Bundler economics: Bundlers such as Pimlico / Stackup / Alchemy / Biconomy package dozens to hundreds of UserOps into 1 件 L2 transaction
per-UserOp distributed cost: Bundled UserOp on Base is ~$0.0003-0.001 (Pimlico 2026 public benchmark), Arbitrum is ~$0.0005-0.002, and Optimism is similar to Base
bundler relationships: Agent platforms typically maintain long-term partnerships with 1-2 bundlers; bundlers adjust batch size in real time according to the L2 fee market
session key + ERC-4337 v0.7+: Agents can request session-scoped keys (amount limits + time limits + contract allowlists), so users do not need to sign every time; this is a key UX breakthrough for commercializing agent payments
ERC-7715 + 7710 (permission proposal)+ ERC-4337 v0.8 (roadmap) further reduce agent permission complexity; compare with ERC-7715 overview · Wallet Permissions and AI Agent auto-payment
bundler centralization risk: The top 5 社 bundlers process ~80%+ of UserOps; bundler exit / regulation / outage affects agent-payment availability

Network effects of Privy / Coinbase CDP / AWS AgentCore defaults

When an agent project selects a wallet provider, L2 selection becomes materially constrained by wallet-provider integration defaults; see embedded wallet network effects moat for details:

Privy creates ETH + Base + Solana wallets by default in AWS Bedrock AgentCore; once an agent goes through the AWS AgentCore route, Base becomes the default settlement chain in most practical integrations
Coinbase CDP uses Base as the default chain in all SDK documentation examples; migration to other L2 requires reconfiguring paymaster / RPC / USDC addresses
WalletConnect / Reown supports multiple chains, but GTM promotes Base + Arbitrum + Optimism + Polygon
AWS / Cloudflare / Vercel edge integration defaults to USDC on Base; compare with x402 edge integration
Actual selection distribution of new agent projects (2025-2026 industry informal survey basis): Base 60-70% / Arbitrum 15-20% / Optimism 5-10% / Polygon 5-10% / Other 5%

CCTP V2 + chain abstraction · agent multi-chain architecture

Agents are not bound to a single L2 ; they use home chain + multi-chain spending:

Home chain pattern: The agent holds stablecoin / token on the home chain (usually Base), and crosses chains via CCTP V2 when spending is needed
CCTP V2 fast finality: USDC burn-mint has 1-3 second finality, and cross-chain transfer per 1 time has a fee of $0.01-0.10
Chain abstraction (compare with chain abstraction patterns): Skip Protocol / Connext / Across / Hyperlane Warp Route and others let the agent sign 1 intent on the source chain, with cross-chain settlement completed by a solver
Typical agent flow: 1) User holds USDC on Base in Coinbase Smart Wallet → 2) agent triggers cross-chain spending → 3) bundler submits UserOp to Base → 4) CCTP V2 burns USDC on Base → 5) mints USDC on target L2 → 6) completes spending on target L2 ; full flow < 30 seconds
Multi-chain agent practice: Most agent payments still complete inside Base; cross-chain scenarios concentrate in DeFi yield optimizers / cross-DEX arbitrage, < 20% of total agent-payment volume

Per-tx measured economics comparison table (2026-Q1)

Workload	Base	Arbitrum	Optimism
EOA simple ETH transfer	~$0.001	~$0.002	~$0.001
EOA USDC transfer	~$0.002	~$0.003	~$0.002
SCA (ERC-4337) create + first sponsored tx	~$0.005-0.015	~$0.01-0.03	~$0.005-0.015
Bundled UserOp (per UserOp distributed)	~$0.0003-0.001	~$0.0005-0.002	~$0.0003-0.001
Uniswap V3 swap	~$0.02-0.10	~$0.05-0.15	~$0.02-0.10
CCTP V2 USDC burn-mint (cross-chain)	~$0.01-0.10 each side	~$0.02-0.15 each side	~$0.01-0.10 each side
GMX perps open / close	n/a (mainly Arbitrum)	~$0.10-0.50	n/a
World mini-app action	n/a	n/a	~$0.001-0.005(on World chain)
Blob congestion-period fee spike	~10-50×	~5-20×	~10-50×

Figures are from L2Beat + DefiLlama + Pimlico bundler benchmarks + Coinbase CDP public examples; actual volatility is high, so consult a real-time gas tracker.

Agent-relevant security / risk-control considerations

session key design: Agent session keys must have chain id restrictions + contract allowlists + amount limits + time limits; otherwise loss is unlimited if stolen
paymaster validation: Paymasters such as CDP / Pimlico run validatePaymasterUserOp before sponsoring; paymasters can reject some malicious contract calls
bundle failure rollback: A single UserOp revert inside a bundled UserOp does not roll back the whole bundle, but the sponsor still bears gas
chain reorg risk: Base / OP Mainnet occasionally have 1-2 block reorgs (rare); agent payments should preferably wait for ~12 blocks confirmation for sensitive transactions
L1 fault proof window: Base / Arbitrum / Optimism all have a 7 -day fault proof window, and withdrawals to L1 require waiting, but this does not affect settlement inside L2
sequencer regulation / sanctions: Coinbase, as a US-regulated entity, may block specific addresses under OFAC sanctions; agents need to consider that sanctioned wallets cannot settle on Base

Agent workload L2 decision tree

General agent payment / micropayment: Base (default, CDP + Smart Wallet + USDC Native)
DeFi-heavy yield / perps / collateral: Arbitrum (deep liquidity + GMX + Pendle)
Enterprise / institutional proprietary agent chain: Arbitrum Orbit or OP Stack self-build (compare with Polygon AggLayer)
World / Worldcoin mini-app agent: Optimism / World
Cross-chain agent (multi-chain settlement): CCTP V2 + use Base as the home chain
KYC-regulated agent: Coinbase CDP on Base (Coinbase risk controls + KYC)

See chain abstraction pattern overview and three chain-abstraction solutions for detailed chain-abstraction routes.

Sources

L2Beat — Base, Arbitrum One, Optimism Mainnet metrics
DefiLlama — chain TVL, stablecoin breakdown
Coinbase Base documentation & blog
Arbitrum documentation — Nitro, Orbit, Stylus, BoLD
Optimism documentation — OP Stack, Superchain, Bedrock
Coinbase CDP documentation — Paymaster, Smart Wallet, Agent Kit
Privy documentation — embedded wallet, AgentCore integration
Alchemy Account Kit documentation
Circle CCTP V2 announcement & docs
Stripe / Visa public blog posts on L2 stablecoin payment integration