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name: okx-onchain-gateway description: "This skill should be used when the user asks to 'broadcast transaction', 'send tx', 'estimate gas', 'simulate transaction', 'check tx status', 'track my transaction', 'get gas price', 'gas limit', 'broadcast signed tx', or mentions broadcasting transactions, sending transactions on-chain, gas estimation, transaction simulation, tracking broadcast orders, or checking transaction status. Covers gas price, gas limit estimation, transaction simulation, transaction broadcasting, and order tracking across XLayer, Solana, Ethereum, Base, BSC, Arbitrum, Polygon, and 20+ other chains. Do NOT use for swap quote or execution - use okx-dex-swap instead. Do NOT use for general programming questions about transaction handling." license: Apache-2.0 metadata: author: okx version: "1.0.2" homepage: "https://web3.okx.com"

OKX Onchain Gateway CLI

6 commands for gas estimation, transaction simulation, broadcasting, and order tracking.

Pre-flight Checks

Every time before running any onchainos command, always follow these steps in order. Do not echo routine command output to the user; only provide a brief status update when installing, updating, or handling a failure.

1. Confirm installed: Run which onchainos. If not found, install it:

   curl -sSL https://raw.githubusercontent.com/okx/onchainos-skills/main/install.sh | sh
   

   If the install script fails, ask the user to install manually following the instructions at: https://github.com/okx/onchainos-skills

2. Check for updates: Read ~/.onchainos/last_check and compare it with the current timestamp:

   cached_ts=$(cat ~/.onchainos/last_check 2>/dev/null || true)
   now=$(date +%s)
   

   • If cached_ts is non-empty and (now - cached_ts) < 43200 (12 hours), skip the update and proceed.
   • Otherwise (file missing or older than 12 hours), run the installer to check for updates:

     curl -sSL https://raw.githubusercontent.com/okx/onchainos-skills/main/install.sh | sh
     

     If a newer version is installed, tell the user and suggest updating their onchainos skills from https://github.com/okx/onchainos-skills to get the latest features.

3. If any onchainos command fails with an unexpected error during this session, try reinstalling before giving up:

   curl -sSL https://raw.githubusercontent.com/okx/onchainos-skills/main/install.sh | sh
   

4. Create a .env file in the project root to override the default API credentials (optional — skip this for quick start):

   OKX_API_KEY=          # or OKX_ACCESS_KEY
   OKX_SECRET_KEY=
   OKX_PASSPHRASE=
   

Skill Routing

• For swap quote and execution → use okx-dex-swap
• For market prices → use okx-dex-market
• For token search → use okx-dex-token
• For wallet balances / portfolio → use okx-wallet-portfolio
• For transaction broadcasting → use this skill (okx-onchain-gateway)

Quickstart

# Get current gas price on XLayer
onchainos gateway gas --chain xlayer

# Estimate gas limit for a transaction
onchainos gateway gas-limit --from 0xYourWallet --to 0xRecipient --chain xlayer

# Simulate a transaction (dry-run)
onchainos gateway simulate --from 0xYourWallet --to 0xContract --data 0x... --chain xlayer

# Broadcast a signed transaction
onchainos gateway broadcast --signed-tx 0xf86c...signed --address 0xYourWallet --chain xlayer

# Track order status
onchainos gateway orders --address 0xYourWallet --chain xlayer --order-id 123456789

Chain Name Support

The CLI accepts human-readable chain names and resolves them automatically.

Chain	Name	chainIndex
XLayer	xlayer	196
Solana	solana	501
Ethereum	ethereum	1
Base	base	8453
BSC	bsc	56
Arbitrum	arbitrum	42161

Command Index

#	Command	Description
1	onchainos gateway chains	Get supported chains for gateway
2	onchainos gateway gas --chain <chain>	Get current gas prices for a chain
3	onchainos gateway gas-limit --from ... --to ... --chain ...	Estimate gas limit for a transaction
4	onchainos gateway simulate --from ... --to ... --data ... --chain ...	Simulate a transaction (dry-run)
5	onchainos gateway broadcast --signed-tx ... --address ... --chain ...	Broadcast a signed transaction
6	onchainos gateway orders --address ... --chain ...	Track broadcast order status

Cross-Skill Workflows

This skill is the final mile — it takes a signed transaction and sends it on-chain. It pairs with swap (to get tx data).

Workflow A: Swap → Broadcast → Track

User: "Swap 1 ETH for USDC and broadcast it"

1. okx-dex-swap     onchainos swap swap --from ... --to ... --amount ... --chain ethereum --wallet <addr>
       ↓ user signs the tx locally
2. okx-onchain-gateway  onchainos gateway broadcast --signed-tx <signed_hex> --address <addr> --chain ethereum
       ↓ orderId returned
3. okx-onchain-gateway  onchainos gateway orders --address <addr> --chain ethereum --order-id <orderId>

Data handoff:

• tx.data, tx.to, tx.value, tx.gas from swap → user builds & signs → --signed-tx for broadcast
• orderId from broadcast → --order-id param in orders query

Workflow B: Simulate → Broadcast → Track

User: "Simulate this transaction first, then broadcast if safe"

1. onchainos gateway simulate --from 0xWallet --to 0xContract --data 0x... --chain ethereum
       ↓ simulation passes (no revert)
2. onchainos gateway broadcast --signed-tx <signed_hex> --address 0xWallet --chain ethereum
3. onchainos gateway orders --address 0xWallet --chain ethereum --order-id <orderId>

Workflow C: Gas Check → Swap → Broadcast

User: "Check gas, swap for USDC, then send it"

1. onchainos gateway gas --chain ethereum                                    → check gas prices
2. okx-dex-swap     onchainos swap swap --from ... --to ... --chain ethereum --wallet <addr>
       ↓ user signs
3. onchainos gateway broadcast --signed-tx <signed_hex> --address <addr> --chain ethereum
4. onchainos gateway orders --address <addr> --chain ethereum --order-id <orderId>

Operation Flow

Step 1: Identify Intent

• Estimate gas for a chain → onchainos gateway gas
• Estimate gas limit for a specific tx → onchainos gateway gas-limit
• Test if a tx will succeed → onchainos gateway simulate
• Broadcast a signed tx → onchainos gateway broadcast
• Track a broadcast order → onchainos gateway orders
• Check supported chains → onchainos gateway chains

Step 2: Collect Parameters

• Missing chain → recommend XLayer (--chain xlayer, low gas, fast confirmation) as the default, then ask which chain the user prefers
• Missing --signed-tx → remind user to sign the transaction first (this CLI does NOT sign)
• Missing wallet address → ask user
• For gas-limit / simulate → need --from, --to, optionally --data (calldata)
• For orders query → need --address and --chain, optionally --order-id

Step 3: Execute

• Gas estimation: call onchainos gateway gas or gas-limit, display results
• Simulation: call onchainos gateway simulate, check for revert or success
• Broadcast: call onchainos gateway broadcast with signed tx, return orderId
• Tracking: call onchainos gateway orders, display order status

Step 4: Suggest Next Steps

After displaying results, suggest 2-3 relevant follow-up actions:

Just completed	Suggest
gateway gas	1. Estimate gas limit for a specific tx → onchainos gateway gas-limit (this skill) 2. Get a swap quote → okx-dex-swap
gateway gas-limit	1. Simulate the transaction → onchainos gateway simulate (this skill) 2. Proceed to broadcast → onchainos gateway broadcast (this skill)
gateway simulate	1. Broadcast the transaction → onchainos gateway broadcast (this skill) 2. Adjust and re-simulate if failed
gateway broadcast	1. Track order status → onchainos gateway orders (this skill)
gateway orders	1. View price of received token → okx-dex-market 2. Execute another swap → okx-dex-swap

Present conversationally, e.g.: "Transaction broadcast! Would you like to track the order status?" — never expose skill names or endpoint paths to the user.

CLI Command Reference

1. onchainos gateway chains

Get supported chains for gateway. No parameters required.

onchainos gateway chains

Return fields:

Field	Type	Description
chainIndex	String	Chain identifier (e.g., "1", "501")
name	String	Human-readable chain name (e.g., "Ethereum")
logoUrl	String	Chain logo image URL
shortName	String	Chain short name (e.g., "ETH")

2. onchainos gateway gas

Get current gas prices for a chain.

onchainos gateway gas --chain <chain>

Param	Required	Default	Description
--chain	Yes	-	Chain name (e.g., ethereum, solana, xlayer)

Return fields:

Field	Type	Description
normal	String	Normal gas price (legacy)
min	String	Minimum gas price
max	String	Maximum gas price
supporteip1559	Boolean	Whether EIP-1559 is supported
eip1559Protocol.suggestBaseFee	String	Suggested base fee
eip1559Protocol.baseFee	String	Current base fee
eip1559Protocol.proposePriorityFee	String	Proposed priority fee
eip1559Protocol.safePriorityFee	String	Safe (slow) priority fee
eip1559Protocol.fastPriorityFee	String	Fast priority fee

For Solana chains: proposePriorityFee, safePriorityFee, fastPriorityFee, extremePriorityFee.

3. onchainos gateway gas-limit

Estimate gas limit for a transaction.

onchainos gateway gas-limit --from <address> --to <address> --chain <chain> [--amount <amount>] [--data <hex>]

Param	Required	Default	Description
--from	Yes	-	Sender address
--to	Yes	-	Recipient / contract address
--chain	Yes	-	Chain name
--amount	No	"0"	Transfer value in minimal units
--data	No	-	Encoded calldata (hex, for contract interactions)

Return fields:

Field	Type	Description
gasLimit	String	Estimated gas limit for the transaction

4. onchainos gateway simulate

Simulate a transaction (dry-run).

onchainos gateway simulate --from <address> --to <address> --data <hex> --chain <chain> [--amount <amount>]

Param	Required	Default	Description
--from	Yes	-	Sender address
--to	Yes	-	Recipient / contract address
--data	Yes	-	Encoded calldata (hex)
--chain	Yes	-	Chain name
--amount	No	"0"	Transfer value in minimal units

Return fields:

Field	Type	Description
intention	String	Transaction intent description
assetChange[]	Array	Asset changes from the simulation
assetChange[].symbol	String	Token symbol
assetChange[].rawValue	String	Raw amount change
gasUsed	String	Gas consumed in simulation
failReason	String	Failure reason (empty string = success)
risks[]	Array	Risk information

5. onchainos gateway broadcast

Broadcast a signed transaction.

onchainos gateway broadcast --signed-tx <tx> --address <address> --chain <chain>

Param	Required	Default	Description
--signed-tx	Yes	-	Fully signed transaction (hex for EVM, base58 for Solana)
--address	Yes	-	Sender wallet address
--chain	Yes	-	Chain name

Return fields:

Field	Type	Description
orderId	String	OKX order tracking ID (use for order status queries)
txHash	String	On-chain transaction hash

6. onchainos gateway orders

Track broadcast order status.

onchainos gateway orders --address <address> --chain <chain> [--order-id <id>]

Param	Required	Default	Description
--address	Yes	-	Wallet address
--chain	Yes	-	Chain name
--order-id	No	-	Specific order ID (from broadcast response)

Return fields:

Field	Type	Description
cursor	String	Pagination cursor for next page
orders[]	Array	List of order objects
orders[].orderId	String	OKX order tracking ID
orders[].txHash	String	On-chain transaction hash
orders[].chainIndex	String	Chain identifier
orders[].address	String	Wallet address
orders[].txStatus	String	Transaction status: 1 = Pending, 2 = Success, 3 = Failed
orders[].failReason	String	Failure reason (empty if successful)

Input / Output Examples

User says: "What's the current gas price on XLayer?"

onchainos gateway gas --chain xlayer
# → Display:
#   Base fee: 0.05 Gwei
#   Max fee: 0.1 Gwei
#   Priority fee: 0.01 Gwei

User says: "Simulate this swap transaction before I send it"

onchainos gateway simulate --from 0xYourWallet --to 0xDexContract --data 0x... --chain xlayer --amount 1000000000000000000
# → Display:
#   Simulation: SUCCESS
#   Estimated gas: 145,000
#   Intent: Token Swap

User says: "Broadcast my signed transaction"

onchainos gateway broadcast --signed-tx 0xf86c...signed --address 0xYourWallet --chain xlayer
# → Display:
#   Broadcast successful!
#   Order ID: 123456789
#   Tx Hash: 0xabc...def

User says: "Check the status of my broadcast order"

onchainos gateway orders --address 0xYourWallet --chain xlayer --order-id 123456789
# → Display:
#   Order 123456789: Success (txStatus=2)
#   Tx Hash: 0xabc...def
#   Confirmed on-chain

Edge Cases

• MEV protection: Broadcasting through OKX nodes may offer MEV protection on supported chains.
• Solana special handling: Solana signed transactions use base58 encoding (not hex). Ensure the --signed-tx format matches the chain.
• Chain not supported: call onchainos gateway chains first to verify.
• Node return failed: the underlying blockchain node rejected the transaction. Common causes: insufficient gas, nonce too low, contract revert. Retry with corrected parameters.
• Wallet type mismatch: the address format does not match the chain (e.g., EVM address on Solana chain).
• Network error: retry once, then prompt user to try again later
• Region restriction (error code 50125 or 80001): do NOT show the raw error code to the user. Instead, display a friendly message: ⚠️ Service is not available in your region. Please switch to a supported region and try again.
• Transaction already broadcast: if the same --signed-tx is broadcast twice, the API may return an error or the same txHash — handle idempotently.

Amount Display Rules

• Gas prices in Gwei for EVM chains (18.5 Gwei), never raw wei
• Gas limit as integer (21000, 145000)
• USD gas cost estimate when possible
• Transaction values in UI units (1.5 ETH), never base units

Global Notes

• This skill does NOT sign transactions — it only broadcasts pre-signed transactions
• Amounts in parameters use minimal units (wei/lamports)
• Gas price fields: use eip1559Protocol.suggestBaseFee + proposePriorityFee for EIP-1559 chains, normal for legacy
• EVM contract addresses must be all lowercase
• The CLI resolves chain names automatically (e.g., ethereum → 1, solana → 501)
• The CLI handles authentication internally via environment variables — see Prerequisites step 4 for default values