debug_traceTransaction

debug_traceTransaction takes one already-mined transaction and replays it instruction by instruction, rebuilding the exact EVM state of the block where it landed and emitting a step-by-step record of execution. That is visibility no plain read method can offer. BNB Smart Chain (BSC) is a PoSA network with roughly three-second blocks where BNB pays gas and BEP-20 tokens flow through venues like PancakeSwap and Venus, so most traces here mean unpicking a DeFi interaction. Point the call at the JSON-RPC endpoint https://bsc.therpc.io/YOUR_API_KEY on chain ID 56. Re-running against historical state is heavy, so it wants a debug-enabled archive node.

Use cases

Pin down why a BEP-20 swap or contract call reverted by reading the opcode and stack contents at the REVERT instruction.
Profile per-opcode gas to find the hot spots worth trimming before a contract ships to mainnet.
Rebuild the full internal call tree of a sandwich or arbitrage bundle with callTracer to study how the transaction moved value.
Capture pre-execution account and storage state through prestateTracer for a security post-mortem after an exploit.

Parameters

#	Name	Type	Required	Description
1	`transactionHash`	string	Yes	Hash of the transaction to trace.
2	`options`	object	No	Tracer configuration object.

Response

Type	Description
object	With the default tracer: `{gas, failed, returnValue, structLogs[]}` where each structLog entry contains `{pc, op, gas, gasCost, depth, stack?, memory?, storage?}`. With callTracer: a nested call-tree object. With prestateTracer: a pre-execution account/storage map.

Example request

1curl https://bsc.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "debug_traceTransaction",
7    "params": [
8        "0x0000000000000000000000000000000000000000000000000000000000000000",
9        {}
10      ],
11    "id": 1
12  }'

Try it live in the BNB Smart Chain playground.

Errors & troubleshooting

Code	Message	Cause
`-32601`	`Method not found`	debug namespace is not enabled on the node (requires --http.api=debug or equivalent).
`-32602`	`Invalid params`	Transaction hash is missing, malformed, or the options object contains unknown fields.
`-32000`	`transaction not found`	The transaction hash does not exist on the chain or the node lacks archive state for that block.

Common pitfalls

Any transaction older than the last few thousand blocks needs full archive state, so a pruned BSC node simply rejects it.
The default structLog stream can swell to hundreds of megabytes on a dense transaction. Switch to callTracer, or just turn off the stack and storage dumps in the options object.
Custom JavaScript tracers run in a sandboxed interpreter and can hit the node timeout on a long-running transaction. Lower tiers may rate-limit or refuse the call outright.

Supported networks

Mainnet — Chain ID: 56
Testnet — Chain ID: 97