web3_clientVersion

web3_clientVersion returns a free-form string identifying the client software running an OP Mainnet node — the OP Stack rollup that settles to Ethereum L1 and uses ETH for gas. OP Mainnet execution nodes typically run op-geth (a fork of Geth), so the string usually resembles a Geth-style identifier with version, platform, and Go build details. Call it at https://optimism.therpc.io/YOUR_API_KEY (chain ID 10, 0xa) to learn which client and version is answering your requests.

Use cases

• Detect the underlying client type and version on OP Mainnet to enable or skip client-specific features such as the txpool namespace, which only op-geth exposes.
• Log the node identity string alongside infrastructure diagnostics so you can correlate behaviour with a specific client build.

Parameters

Cette méthode ne prend aucun paramètre. Passez un tableau vide [].

Response

Example request

1curl https://optimism.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "web3_clientVersion",
7    "params": [],
8    "id": 1
9  }'

Try it live in the Optimism playground.

Errors & troubleshooting

Common pitfalls

• Managed endpoints such as optimism.therpc.io may return a custom or redacted string rather than the exact underlying op-geth version, so do not assume it reflects a specific patch level.
• Avoid using this string as your sole feature-detection signal in production — probe the method you actually need (for example, call txpool_status and handle "method not found") rather than parsing the version text.

Supported networks

• Mainnet — Chain ID: 10
• Sepolia — Chain ID: 11155420

See also

• net_version

1curl https://optimism.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H 'Content-Type: application/json' \
4  -d '{"jsonrpc":"2.0","id":1,"method":"web3_clientVersion","params":[]}'