debug_getBadBlocks

debug_getBadBlocks returns the list of invalid blocks an OP Mainnet node has seen and rejected since it last started — blocks that failed validation and never entered the canonical chain that settles to Ethereum L1. OP Mainnet is an OP Stack optimistic rollup where gas and value move in ETH, so this method surfaces malformed or consensus-breaking blocks that op-geth refused to import rather than anything about token balances. Send the request to https://optimism.therpc.io/YOUR_API_KEY (chain ID 10, 0xa); each entry carries the block hash, the decoded header, and the raw RLP so you can inspect exactly what was rejected.

Use cases

• Detect consensus violations or malformed blocks propagated to your OP Mainnet node by misbehaving peers in the Superchain p2p mesh.
• Investigate fork events by examining the rejected alternative block alongside the canonical one that op-geth kept.
• Audit op-geth validation logic by comparing rejected blocks against OP Stack Bedrock protocol rules.

Parameters

هذا الأسلوب لا يأخذ أي معاملات. مرر مصفوفة فارغة [].

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": "debug_getBadBlocks",
7    "params": [],
8    "id": 1
9  }'

Try it live in the Optimism playground.

Errors & troubleshooting

Common pitfalls

• The bad-block list lives in memory only and is wiped when the op-geth node restarts, so a fresh node always reports an empty array.
• A healthy OP Mainnet node rarely accumulates bad blocks, so an empty result is the normal, expected response — not an error.
• Not every OP Stack execution client implements this method; some return -32601 if the debug namespace is unavailable.

Supported networks

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

See also

• debug_traceBlock
• debug_traceBlockByHash
• debug_traceBlockByNumber

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":"debug_getBadBlocks","params":[]}'