get_bridge_instructions - Documentation

Overview

Retrieves cross-chain bridge guides for Cronos (Gravity Bridge and IBC). Tool Name: get_bridge_instructions

Parameters

action

enum

required

Action to performOptions: "get", "search", "list", "route"

bridge_id

string

Bridge ID (required for "get" action)

query

string

Search query (required for "search" action)

bridge_type

enum

Filter by bridge typeOptions: "gravity", "ibc"

from_chain

string

Source chain (required for "route" action)

to_chain

string

Destination chain (required for "route" action)

Available Bridges

Gravity Bridge
IBC

Bridge ID	From	To	Time	Assets
`cronos-pos-to-evm`	Cronos POS	Cronos EVM	2-5 min	CRO, ATOM
`cronos-evm-to-pos`	Cronos EVM	Cronos POS	2-5 min	CRO

Bridge ID	From	To	Time	Assets
`cronos-to-osmosis`	Cronos POS	Osmosis	30-60 sec	CRO, ATOM
`cronos-to-cosmos`	Cronos POS	Cosmos Hub	30-60 sec	CRO, ATOM

Response

{
  "found": true,
  "action": "get",
  "guides": [
    {
      "id": "cronos-pos-to-evm",
      "from_chain": "Cronos POS",
      "to_chain": "Cronos EVM",
      "bridge_type": "gravity",
      "estimated_time": "2-5 minutes",
      "supported_assets": ["CRO", "ATOM"],
      "fees": {
        "network_fee": "~0.001 CRO",
        "bridge_fee": "0%",
        "total_estimate": "~0.001 CRO"
      },
      "requirements": [
        "Keplr wallet installed",
        "MetaMask wallet installed",
        "Minimum balance: 0.01 CRO"
      ],
      "steps": [
        {
          "step_number": 1,
          "action": "Connect Keplr wallet to Cronos POS",
          "ui_action": "Open https://cronos.org/gravity and click 'Connect Keplr'",
          "note": "Ensure you're on Cronos POS network"
        },
        {
          "step_number": 2,
          "action": "Approve IBC transfer",
          "command": "cronosd tx ibc-transfer transfer transfer channel-0 ...",
          "wait_time": "1-2 minutes for confirmation"
        }
      ],
      "code_example": "// TypeScript example\nimport { GravityBridge } from '@cronos/bridge';\n...",
      "warnings": [
        "Ensure sufficient balance for fees",
        "Double-check recipient address"
      ],
      "github_source": "https://github.com/cronos-labs/bridge-guides"
    }
  ]
}

Example Usage

Get Specific Bridge Guide

result = use_mcp_tool(
    server_name="cato",
    tool_name="get_bridge_instructions",
    arguments={
        "action": "get",
        "bridge_id": "cronos-pos-to-evm"
    }
)

Find Route Between Chains

result = use_mcp_tool(
    server_name="cato",
    tool_name="get_bridge_instructions",
    arguments={
        "action": "route",
        "from_chain": "pos",
        "to_chain": "evm"
    }
)

Search Bridge Guides

result = use_mcp_tool(
    server_name="cato",
    tool_name="get_bridge_instructions",
    arguments={
        "action": "search",
        "query": "osmosis"
    }
)

List All Bridges

result = use_mcp_tool(
    server_name="cato",
    tool_name="get_bridge_instructions",
    arguments={
        "action": "list"
    }
)

Bridge Types

Gravity Bridge

Connects Cronos POS and Cronos EVM chainsFeatures:

Bidirectional transfers
2-5 minute transfer time
Low fees (~0.001 CRO)
Supports CRO and ATOM

Use cases: Move assets between POS and EVM chains

IBC (Inter-Blockchain Communication)

IBC Protocol

Connects Cronos POS to Cosmos ecosystemFeatures:

Fast transfers (30-60 seconds)
Native Cosmos protocol
Wide ecosystem support
Secure and trustless

Use cases: Bridge to Osmosis, Cosmos Hub, other IBC chains

Step-by-Step Bridge Guides

Cronos POS → EVM

Connect Keplr Wallet

Open Cronos Gravity Bridge
Click “Connect Keplr”
Approve connection in Keplr popup

Enter Bridge Details

Select CRO or ATOM token
Enter amount to bridge
Enter MetaMask address as destination
Review fees and estimated time

Approve & Execute

Click “Bridge”
Confirm transaction in Keplr
Wait 2-5 minutes for completion
Tokens appear in MetaMask

Verify Receipt

Check balance in MetaMask on Cronos EVM

Cronos EVM → POS

Connect MetaMask

Open Cronos Gravity Bridge
Click “Connect MetaMask”
Select Cronos EVM network

Enter Bridge Details

Select CRO token
Enter amount to bridge
Enter Keplr address (cro1…) as destination
Review fees

Approve & Execute

Approve token if needed
Click “Bridge”
Confirm in MetaMask
Wait 2-5 minutes

Verify Receipt

Check balance in Keplr on Cronos POS

Cronos POS → Osmosis (IBC)

Open Keplr

Ensure Keplr is connected to Cronos POS

Use IBC Transfer

cronosd tx ibc-transfer transfer transfer \
  channel-5 \
  osmo1... \
  1000000basecro \
  --from mykey \
  --chain-id cronos_25-1 \
  --fees 5000basecro

Wait for Confirmation

IBC transfers complete in 30-60 seconds

Verify on Osmosis

Check balance on Osmosis chain

Fee Structure

Gravity Bridge
IBC

Fee Type	Amount	Description
Network Fee	~0.001 CRO	Gas fee for transaction
Bridge Fee	0%	No additional bridge fee
Total	~0.001 CRO	Very affordable

Fee Type	Amount	Description
Network Fee	~0.005 CRO	Cosmos SDK gas fee
Relayer Fee	0%	Typically none
Total	~0.005 CRO	Minimal cost

Requirements

Wallet Requirements

Keplr Wallet

Required for Cronos POS interactions

Install from keplr.app
Add Cronos POS chain
Fund with CRO for fees

MetaMask

Required for Cronos EVM interactions

Install from metamask.io
Add Cronos EVM network
Fund with CRO for fees

Minimum Balances

Ensure you have sufficient balances:

Bridge amount: Your desired transfer amount
Gas fees: At least 0.01 CRO extra
Total: Bridge amount + fees

Common Bridge Routes

Within Cronos Ecosystem

POS ↔ EVM

Use Gravity Bridge
2-5 minute transfers
Supports CRO, ATOM
Lowest fees

To Cosmos Ecosystem

POS → Osmosis/Cosmos Hub

Use IBC protocol
30-60 second transfers
Native Cosmos integration
Wider asset support

From Other Chains

Ethereum/Other EVMs → Cronos

Use third-party bridges (Multichain, etc.)
Longer transfer times
Higher fees
Check bridge reputation

Code Examples

TypeScript - Gravity Bridge

import { GravityBridge } from '@cronos/bridge';

// Initialize bridge
const bridge = new GravityBridge({
  posRpc: 'https://rpc.cronos.org:26657',
  evmRpc: 'https://evm.cronos.org'
});

// Bridge from POS to EVM
const tx = await bridge.bridgeToEVM({
  from: 'cro1...',
  to: '0x...',
  amount: '1000000000000000000', // 1 CRO
  token: 'CRO'
});

console.log('Transaction:', tx.hash);

Python - IBC Transfer

from cosmospy import Transaction

# Create IBC transfer
tx = Transaction(
    privkey='your_private_key',
    chain_id='cronos_25-1',
    rpc='https://rpc.cronos.org:26657'
)

result = tx.ibc_transfer(
    receiver='osmo1...',
    amount=1000000,  # 1 CRO
    denom='basecro',
    channel='channel-5',
    timeout_height=100000
)

print('TX Hash:', result['txhash'])

Troubleshooting

Transaction Pending Too Long

Gravity Bridge: Should complete in 2-5 minutes

Check network status
Verify sufficient gas fees
Contact support if >10 minutes

IBC: Should complete in 30-60 seconds

Check channel status
Verify packet was relayed

Insufficient Balance

Solution:

Ensure you have enough for amount + fees
Keep at least 0.01 CRO extra
Check both source and destination chains

Wrong Address Format

Solution:

POS addresses: cro1… (Bech32)
EVM addresses: 0x… (Ethereum format)
Double-check before confirming

Wallet Not Connected

Solution:

Refresh browser
Check wallet extension is unlocked
Ensure correct network selected
Try disconnecting and reconnecting

Best Practices

Safety Checklist✅ Verify recipient address format
✅ Start with small test amount
✅ Ensure sufficient gas fees
✅ Check network status before bridging
✅ Save transaction hash for reference
✅ Wait for confirmations before proceeding

Optimization Tips

Bridge during low network congestion for faster transfers
Batch multiple transfers to save on gas
Keep some native tokens on both chains for future fees
Bookmark bridge interfaces for quick access

get_unified_portfolio

Check balances across all chains

query_cronos_sdk_docs

Find bridge integration examples

​Overview

​Parameters

​Available Bridges

​Response

​Example Usage

​Get Specific Bridge Guide

​Find Route Between Chains

​Search Bridge Guides

​List All Bridges

​Bridge Types

​Gravity Bridge

Gravity Bridge

​IBC (Inter-Blockchain Communication)

IBC Protocol

​Step-by-Step Bridge Guides

​Cronos POS → EVM

​Cronos EVM → POS

​Cronos POS → Osmosis (IBC)

​Fee Structure

​Requirements

​Wallet Requirements

Keplr Wallet

MetaMask

​Minimum Balances

​Common Bridge Routes

​Code Examples

​TypeScript - Gravity Bridge

​Python - IBC Transfer

​Troubleshooting

​Best Practices

​Related Tools

get_unified_portfolio

query_cronos_sdk_docs

Overview

Parameters

Available Bridges

Response

Example Usage

Get Specific Bridge Guide

Find Route Between Chains

Search Bridge Guides

List All Bridges

Bridge Types

Gravity Bridge

IBC (Inter-Blockchain Communication)

Step-by-Step Bridge Guides

Cronos POS → EVM

Cronos EVM → POS

Cronos POS → Osmosis (IBC)

Fee Structure

Requirements

Wallet Requirements

Minimum Balances

Common Bridge Routes

Code Examples

TypeScript - Gravity Bridge

Python - IBC Transfer

Troubleshooting

Best Practices

Related Tools