# Otto AI x402 — Cross-Chain Bridge

> Otto AI x402 — Cross-Chain Bridge is a paid API for AI agents from x402.ottoai.services, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Bridges tokens from one blockchain network to another (e.g., Base to Arbitrum), returning a transaction hash and estimated completion time.

## Facts

- Endpoint: POST https://x402.ottoai.services/bridge
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/otto-ai-x402-cross-chain-bridge-b28336c2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OHVBQDS_C79hpPVoeURQm

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability otto-ai-x402-cross-chain-bridge-b28336c2 -d '<json body>'
```

Example prompt: Bridge my USDC from Base to Arbitrum — I want to move about 100 USDC and need to know when it'll complete.

## When to prefer this

Use this endpoint when you need to programmatically move tokens between supported blockchain networks (Base, Polygon, Arbitrum, Solana, Ethereum) via a pay-per-call x402 micropayment model. Prefer this over manual bridge UIs when automating DeFi workflows or agent-driven cross-chain asset management within the Otto AI ecosystem.

## Known failure modes

- Unsupported chain pair — returns error if fromChain/toChain combination is not supported
- Insufficient balance — transaction fails if wallet lacks enough tokens
- Payment failure — x402 USDC micropayment not confirmed, call rejected
- Bridge congestion — estimated completion time may be significantly higher than usual
- Invalid wallet address — malformed address returns validation error

## How this service works

Cross-chain token bridging via LiFi aggregator. Move tokens between Base, Ethereum, Arbitrum, Optimism, Polygon, BSC, Avalanche, and Solana with best-route execution across all major bridges.

## Output

Returns a JSON object with a success flag, the source chain (fromChain), destination chain (toChain), the on-chain bridge transaction hash (bridgeTxHash starting with 0x...), and an estimated completion time in seconds (e.g. 180 seconds for Base to Arbitrum).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "amount": {
   "type": "number",
   "description": "Amount to bridge (human-readable). Decimals are derived server-side — do NOT send fromDecimals."
  },
  "toSymbol": {
   "type": "string",
   "description": "Destination token: a known symbol OR a 0x contract address, resolved on the DESTINATION chain."
  },
  "toChainId": {
   "type": "number",
   "description": "Destination chain ID"
  },
  "fromSymbol": {
   "type": "string",
   "description": "Source token: a known symbol OR a 0x contract address, resolved on the SOURCE chain. Ambiguous symbols are rejected (HTTP 400) with candidates."
  },
  "fromChainId": {
   "type": "number",
   "description": "Source chain ID (8453 Base, 1 Ethereum, 42161 Arbitrum, 137 Polygon, 56 BSC, 43114 Avalanche, 10 Optimism)"
  },
  "tokenSource": {
   "enum": [
    "butler_wallet",
    "otto_safe",
    "auto"
   ],
   "type": "string",
   "description": "Funds source (default: auto)"
  },
  "toTokenAddress": {
   "type": "string",
   "description": "Destination token contract address (alternative to toSymbol)."
  },
  "fromTokenAddress": {
   "type": "string",
   "description": "Source token contract address (alternative to fromSymbol). If both are sent and disagree, the request is rejected."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "success": true,
  "toChain": "Arbitrum",
  "fromChain": "Base",
  "bridgeTxHash": "0x...",
  "estimatedCompletionSeconds": 180
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/otto-ai-x402-cross-chain-bridge-b28336c2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.ottoai.services](https://www.zero.xyz/host/x402.ottoai.services/llms.txt)