# Cross-Chain Bridge Rate Aggregator (LiFi Multi-Protocol)

> Cross-Chain Bridge Rate Aggregator (LiFi Multi-Protocol) is a paid API for AI agents from x402-deployer.x402-deployer.workers.dev, paid per call via x402, $0.03/call, status unknown (last checked 2026-09-15).

Aggregates and returns best bridge rates across Across, Stargate, Hop, deBridge, Synapse, and CCTP for cross-chain token transfers

## Facts

- Endpoint: POST https://x402-deployer.x402-deployer.workers.dev/bridge-rates
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-deployer-x402-deployer-workers-dev-4246ad28
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3hk7DyzXf1RHhzky2lDyn

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 x402-deployer-x402-deployer-workers-dev-4246ad28 -d '<json body>'
```

Example prompt: What's the best bridge rate to move 500 USDC from Ethereum mainnet to Arbitrum right now — compare all the major protocols like Across, Stargate, and Hop and tell me which has the lowest fees and fastest settlement.

## When to prefer this

Use this endpoint when you need to compare bridge rates across multiple protocols simultaneously rather than querying each bridge API individually. Ideal for DeFi agents that need to route cross-chain transfers optimally by cost or speed, and when you want a single aggregated view covering the most popular bridge protocols including Across, Stargate, Hop, deBridge, Synapse, and CCTP.

## Known failure modes

- Unsupported token/chain pair returns no quotes or empty results
- Invalid chain ID or token address returns a 400 error
- One or more underlying bridge protocols temporarily unavailable, resulting in partial quote set
- Amount too low for bridge minimums returns an error or filtered results
- Network congestion causes stale or delayed rate data

## How this service works

Cross-chain bridge rate aggregator. LiFi public quote API aggregates Across, Stargate, Hop, deBridge, Synapse, CCTP. Free, commercial-OK with attribution.

## Output

Returns aggregated bridge quotes from multiple protocols (Across, Stargate, Hop, deBridge, Synapse, CCTP), including estimated output amount, fees, slippage, estimated transfer time, and the recommended best route ranked by cost or speed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "required": [
      "from_chain",
      "to_chain",
      "from_token",
      "to_token",
      "amount"
     ],
     "properties": {
      "limit": {
       "type": "number",
       "description": "Max routes to return. 1-10. Default 5."
      },
      "amount": {
       "type": "string",
       "description": "Source amount in the token's smallest unit (e.g. wei for ETH, '1000000000000000000' = 1 ETH; '1000000' = 1 USDC at 6 decimals)."
      },
      "slippage": {
       "type": "number",
       "description": "Max slippage as decimal fraction (0.01 = 1%). Default 0.005."
      },
      "to_chain": {
       "type": "number",
       "description": "Destination chain id (same id space as from_chain)."
      },
      "to_token": {
       "type": "string",
       "description": "Destination token contract address. Same '0x000...' convention for native."
      },
      "from_chain": {
       "type": "number",
       "description": "Source chain id. EVM chain id (1=Ethereum, 8453=Base, 42161=Arbitrum One, 10=Optimism, 137=Polygon, 56=BNB Chain)."
      },
      "from_token": {
       "type": "string",
       "description": "Source token contract address. Use '0x0000000000000000000000000000000000000000' for the chain's native gas token (ETH, MATIC, BNB)."
      },
      "to_address": {
       "type": "string",
       "description": "Optional EVM destination address. Defaults to from_address."
      },
      "from_address": {
       "type": "string",
       "description": "Optional EVM address of the sender. Required for slippage-checked + ready-to-sign quotes."
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "routes": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "to
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-deployer-x402-deployer-workers-dev-4246ad28/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-deployer.x402-deployer.workers.dev](https://www.zero.xyz/host/x402-deployer.x402-deployer.workers.dev/llms.txt)