8 Chains · Bridge Aggregation · Best Route

Cross-Chain Bridge API
for AI Agents

Move tokens between Ethereum, Arbitrum, Base, Optimism, Polygon, BNB Chain, Solana, and Tron in a single API call. Purple Flea aggregates 10+ bridging protocols and automatically selects the cheapest, fastest, and most reliable route for every transfer.

Ethereum
Arbitrum
Base
Optimism
Polygon
BNB Chain
Solana
Tron
Avalanche
zkSync
Use Cases

Why AI agents need cross-chain bridging

AI agents operating in DeFi rarely stay on a single chain. Capital efficiency demands going wherever yield is highest, liquidity is deepest, or fees are lowest. A yield-farming agent might earn USDC on Base, bridge to Arbitrum for a higher-rate Aave market, then swing to Polygon for a Curve pool opportunity — all within the same strategy loop.

Arbitrage agents constantly exploit price differences that exist because liquidity is fragmented across chains. Cross-chain arbitrage between Uniswap on Ethereum and SushiSwap on Arbitrum requires reliable, low-latency bridging that an agent can call programmatically without manual intervention.

Agents that follow users across ecosystems also need bridging. A personal finance agent serving a user who operates across Base and Solana must be able to move that user's funds between chains on demand, without the user needing to manually interact with bridge UIs.

Purple Flea's bridge API abstracts all of this complexity into a single endpoint. Pass in the token, amount, source chain, and destination chain. The API handles route selection, protocol interaction, gas management, and status monitoring.

Protocols

10+ bridging protocols, one unified API

Rather than integrating each bridge directly, Purple Flea evaluates all available routes in real time and returns the best option based on your configured preferences (lowest fee, fastest settlement, or highest historical reliability).

Stargate (LayerZero)
Native asset bridging over LayerZero's omnichain messaging. Supports USDC, USDT, ETH across most major EVM chains. Deep liquidity pools.
Most liquid
Across Protocol
Intent-based bridge with relayer network. Typically 1-5 minute settlements with competitive fees. Strong on ETH, USDC, USDT.
Fastest EVM
Circle CCTP
Circle's native USDC bridging protocol. Burns on source chain, mints on destination. No wrapped tokens. No bridge risk. 1-2 minute settlement.
Native USDC
Hop Protocol
Optimistic rollup bridge focused on L2-to-L2 transfers. Best for ETH and stablecoins between Arbitrum, Optimism, Base, and Polygon.
L2 specialist
Wormhole
Cross-chain messaging protocol supporting EVM, Solana, and non-EVM chains. Best route when bridging between EVM and Solana ecosystems.
Solana support
deBridge
Decentralized bridging with on-chain validation. Competitive on Arbitrum, BNB, and Polygon. DLN (deBridge Liquidity Network) for fast routes.
Low fee
Connext
Trustless cross-chain communication protocol. AAMM-based liquidity for stablecoins. Strong on Optimism and Arbitrum.
Trustless
Synapse Protocol
Multi-chain AMM + bridge. Supports a broad range of tokens and chains including non-EVM. Good fallback for tokens not covered by larger bridges.
Broad token support
Celer cBridge
State channel-based bridging with fast optimistic mode. Reliable fallback for chains and tokens that other bridges do not cover.
Reliable fallback
Best route selection: For each bridge request, Purple Flea queries available routes from all supported protocols simultaneously, then ranks by fee, estimated time, and recent reliability score. The winning route is returned and executed automatically. You can also override to pin a specific bridge.
Native USDC

Circle CCTP: no wrapped tokens, no bridge risk

Most bridges work by locking tokens on the source chain and issuing a synthetic “wrapped” version on the destination. Wrapped tokens introduce smart contract risk: if the bridge is exploited, the wrapped tokens become worthless.

Circle CCTP (Cross-Chain Transfer Protocol) works differently. When you bridge USDC via CCTP, the tokens are burned on the source chain and minted fresh by Circle on the destination chain. There is no bridge custodying your USDC. The destination tokens are 100% native, not wrapped.

🔥
Burn and mint model
USDC is burned on the source chain. Circle attests the burn. Native USDC is minted on destination. No wrapped token exposure at any point.
⏳
1-2 minute settlement
Circle's attestation service typically finalizes within 1-2 minutes. Faster than most lock-and-mint bridges which require longer confirmation windows.
💰
~$0.50 fee
CCTP charges a flat attestation fee regardless of transfer size. For large USDC transfers (over $1,000), CCTP is almost always the cheapest option.
🌐
8 chains supported
CCTP currently supports Ethereum, Arbitrum, Base, Optimism, Polygon, Avalanche, Solana, and Tron — the same chains Purple Flea covers natively.
🔒
No bridge contract risk
CCTP is operated by Circle, the USDC issuer. There is no third-party bridge smart contract that can be exploited. The attestation model is audited and battle-tested.
✅
Auto-selected for USDC
When you request a USDC bridge and CCTP is available for the route, Purple Flea automatically selects CCTP as the default. Override with protocol: "stargate" if needed.
Code Examples

Bridge in three API calls

Get a quote, execute the bridge, then poll for status. All three steps use the same Purple Flea API key. No separate bridge accounts or credentials needed.

bridge-usdc-eth-to-base.js
// Bridge 10,000 USDC from Ethereum to Base via best route (auto-selects CCTP) const PURPLE_FLEA_API_KEY = process.env.PURPLE_FLEA_API_KEY; const BASE_URL = 'https://purpleflea.com/v1'; async function bridgeUSDC(amount = 10000) { // Step 1: Get best route quote const quoteRes = await fetch(`${BASE_URL}/bridge/quote`, { method: 'POST', headers: { 'Authorization': `Bearer ${PURPLE_FLEA_API_KEY}`, 'Content-Type': 'application/json' }, body: JSON.stringify({ token: 'USDC', amount: amount, from_chain: 'ethereum', to_chain: 'base' }) }); const quote = await quoteRes.json(); console.log(`Best route: ${quote.protocol}`); console.log(`Fee: $${quote.fee_usd.toFixed(4)}`); console.log(`Est. time: ${quote.estimated_seconds}s`); // Step 2: Execute the bridge const bridgeRes = await fetch(`${BASE_URL}/bridge/execute`, { method: 'POST', headers: { 'Authorization': `Bearer ${PURPLE_FLEA_API_KEY}`, 'Content-Type': 'application/json' }, body: JSON.stringify({ quote_id: quote.quote_id, from_address: '0xYourAgentAddress...', to_address: '0xYourAgentAddress...' // same address, different chain }) }); const bridge = await bridgeRes.json(); console.log(`Bridge tx: ${bridge.source_tx_hash}`); console.log(`Bridge ID: ${bridge.bridge_id}`); return bridge.bridge_id; } bridgeUSDC(10000).catch(console.error);
bridge-eth-to-arbitrum.js
// Bridge 1 ETH from Ethereum to Arbitrum (best route: Across or Stargate) async function bridgeETH(amountEth = 1.0) { const quoteRes = await fetch('https://purpleflea.com/v1/bridge/quote', { method: 'POST', headers: { 'Authorization': `Bearer ${process.env.PURPLE_FLEA_API_KEY}`, 'Content-Type': 'application/json' }, body: JSON.stringify({ token: 'ETH', amount: amountEth, from_chain: 'ethereum', to_chain: 'arbitrum', preference: 'fastest' // 'cheapest' | 'fastest' | 'safest' }) }); const quote = await quoteRes.json(); const executeRes = await fetch('https://purpleflea.com/v1/bridge/execute', { method: 'POST', headers: { 'Authorization': `Bearer ${process.env.PURPLE_FLEA_API_KEY}`, 'Content-Type': 'application/json' }, body: JSON.stringify({ quote_id: quote.quote_id, from_address: '0xYourAgentAddress...', to_address: '0xYourAgentAddress...' }) }); const result = await executeRes.json(); return result; } bridgeETH(1.0).catch(console.error);
monitor-bridge-status.js
// Poll bridge status until confirmed on destination chain async function waitForBridge(bridgeId, timeoutMs = 300000) { const start = Date.now(); while (Date.now() - start < timeoutMs) { const res = await fetch(`https://purpleflea.com/v1/bridge/status/${bridgeId}`, { headers: { 'Authorization': `Bearer ${process.env.PURPLE_FLEA_API_KEY}` } }); const status = await res.json(); console.log(`Status: ${status.status} | ${status.message}`); if (status.status === 'completed') { console.log(`Destination tx: ${status.destination_tx_hash}`); console.log(`Amount received: ${status.received_amount} ${status.token}`); return status; } if (status.status === 'failed') { throw new Error(`Bridge failed: ${status.error}`); } // Poll every 10 seconds await new Promise(r => setTimeout(r, 10000)); } throw new Error('Bridge timed out'); } // Usage: const bridgeId = await bridgeUSDC(10000); const result = await waitForBridge(bridgeId); console.log('Bridge complete:', result);
Bridge Comparison

Bridge fee comparison: 10,000 USDC, Ethereum to Arbitrum

Fees vary by bridge, time of day, and network congestion. The table below shows typical fees under normal network conditions. Purple Flea's best-route selector evaluates these in real time.

Bridge Fee (10k USDC) Est. Time Token Type Reliability
Circle CCTP ~$0.50 1–2 min Native USDC Excellent
Stargate (LayerZero) ~$2–4 3–10 min Pool USDC Excellent
Across Protocol ~$1–3 1–5 min Pool USDC Excellent
Hop Protocol ~$3–6 5–15 min hUSDC Good
Synapse Protocol ~$4–8 5–20 min nUSD Good
Celer cBridge ~$2–5 3–15 min Pool USDC Good
Auto-selection in action: For a 10,000 USDC Ethereum → Arbitrum bridge, Purple Flea's best-route engine selects Circle CCTP by default, saving $1.50–$7.50 compared to alternatives while providing faster settlement and no wrapped token risk.
Safety

Bridge health monitoring and automatic failover

Bridge exploits have resulted in over $2 billion in losses across the industry. Purple Flea actively monitors the health of all integrated bridges and automatically removes any bridge from the routing pool if anomalies are detected.

The monitoring system tracks: bridge contract TVL changes (sudden drops signal a potential exploit), transaction success rate on each bridge (drops below 95% trigger review), settlement time deviation (if a bridge is taking 3x longer than normal, it is deprioritized), and liquidity depth (bridges with thin pools are penalized in route scoring to avoid high slippage).

🚑
TVL anomaly detection
Real-time TVL monitoring for all bridge contracts. A sudden outflow of more than 10% in under 60 seconds triggers an automatic bridge disable.
📈
Success rate tracking
Purple Flea tracks the rolling 24h success rate for each bridge. Bridges below 97% are automatically down-weighted in route scoring.
⏩
Automatic failover
If a bridge is disabled mid-transfer, Purple Flea retries via the next-best route automatically. Your agent does not need to handle bridge-level failures.
🔠
Bridge status endpoint
Query GET /v1/bridge/health to see the current status of all integrated bridges. Useful for agents that want to pre-screen before initiating transfers.
🔔
Incident alerts
Subscribe to bridge incident alerts via Telegram or webhook. Your agent receives notification within seconds if a bridge it uses is taken offline.
🖌
Audit trail
Every bridge transaction is logged with source tx hash, destination tx hash, protocol used, fee paid, and settlement time. Full history queryable via API.
Security note: No bridge is risk-free. Purple Flea's monitoring reduces risk but cannot guarantee against novel exploits. For large transfers, consider splitting into multiple smaller transactions across different bridges (the API supports multi-route splitting natively via split_routes: true).