# debug\_traceTransaction ### Parameters 1. `Transaction Hash`. 2. `Tracer` - choose from one of these options: * `4byteTracer` - Solidity contract functions are [addressed](https://docs.soliditylang.org/en/develop/abi-spec.html#function-selector) using the first four byte of the Keccak-256 hash of their signature. This `tracer` monitors and analyzes the usage of specific function signatures within smart contracts by capturing their unique first four bytes. * `callTracer` - collects data about all call frames executed within a transaction, creating a hierarchical list of call frames structured mirroring the EVM's operations. This is useful for debugging and analytical purposes. * `prestateTracer` - captures and analyzes the state of the blockchain before the execution of a specific transaction. It helps in understanding the state changes and effects that a transaction will have on the blockchain's data and accounts before the transaction is actually executed. * `noopTracer` - returns empty results. This is used for testing purpose. * `opcountTracer` - count and track the number of operations (or opcodes) executed during a specific transaction. * `unigramTracer` - counts the frequency of occurrence of each opcode. * `bigramTracer` - a bigram refers to a sequence of two bytes or characters. This tracer is designed to observe and provide insights into the patterns and occurrences of these two-byte sequences as they appear within the data of executed transactions. * `trigramTracer` - a trigram refers to a sequence of three bytes or characters. This tracer is designed to observe and provide insights into the patterns and occurrences of these three-byte sequences as they appear within the data of executed transactions. * `evmdisTracer` - generates the bytecode disassembly of executed transactions, providing developers with insights into how smart contracts operate at a low-level bytecode level for debugging, security audits, and performance optimization purposes. #### Sample Request {% code overflow="wrap" %} ``` curl https://lb.nodies.app/v1/ \ -H "x-api-key: " \ -X POST \ -H "Content-Type: application/json" \ -d '{ "method": "debug_traceTransaction", "params": [ "0x38f92e54c90766253656beaa11f91102e8ad5bd6e6dad0f526c9998900caadf0", { "tracer": "bigramTracer" } ], "id": 1, "jsonrpc": "2.0" }' ``` {% endcode %} #### Sample Response {% code overflow="wrap" %} ``` { "jsonrpc": "2.0", "id": 1, "result": { "ADD-CALLDATALOAD": 1, "ADD-PUSH2": 1, "ADD-SWAP1": 2, "ADDRESS-EQ": 1, "AND-ADDRESS": 1, "AND-CALLER": 1, "AND-DUP2": 2, "AND-DUP5": 1, "AND-EQ": 1, "AND-ISZERO": 1, "AND-PUSH1": 2, "AND-PUSH2": 2, "AND-PUSH32": 1, "AND-SWAP2": 2, "CALLDATACOPY-PUSH1": 1, "CALLDATALOAD-PUSH1": 3, "CALLDATALOAD-SWAP4": 1, "CALLDATASIZE-LT": 2, "CALLDATASIZE-PUSH1": 3, "CALLER-DUP5": 1, "CALLER-PUSH1": 2, "CALLVALUE-DUP1": 1, "DUP1-CALLDATACOPY": 1, "DUP1-CALLDATALOAD": 1, "DUP1-CALLDATASIZE": 1, "DUP1-DUP1": 1, "DUP1-DUP3": 1, "DUP1-DUP6": 1, "DUP1-ISZERO": 2, "DUP1-PUSH1": 1, "DUP1-PUSH4": 10, "DUP1-RETURNDATACOPY": 1, "DUP1-SLOAD": 1, "DUP1-SWAP2": 2, "DUP2-AND": 1, "DUP2-DUP2": 1, "DUP2-EQ": 1, "DUP2-KECCAK256": 2, "DUP2-LT": 1, "DUP2-MSTORE": 6, "DUP2-SWAP1": 1, "DUP3-AND": 1, "DUP3-GT": 1, "DUP3-KECCAK256": 1, "DUP3-NOT": 1, "DUP3-PUSH1": 1, "DUP4-AND": 3, "DUP4-DUP4": 1, "DUP4-DUP6": 1, "DUP4-PUSH2": 2, "DUP5-DUP5": 1, "DUP5-GAS": 1, "DUP5-PUSH1": 2, "DUP5-PUSH2": 1, "DUP5-SWAP1": 1, "DUP5-SWAP3": 1, "DUP6-AND": 2, "DUP6-DUP6": 1, "DUP6-SUB": 2, "EQ-ISZERO": 2, "EQ-PUSH2": 8, "GAS-DELEGATECALL": 1, "GT-ISZERO": 1, "GT-PUSH2": 3, "ISZERO-DUP2": 1, "ISZERO-ISZERO": 1, "ISZERO-PUSH2": 8, "JUMP-JUMPDEST": 27, "JUMPDEST-CALLDATASIZE": 1, "JUMPDEST-CALLER": 1, "JUMPDEST-DUP1": 2, "JUMPDEST-JUMP": 1, "JUMPDEST-POP": 4, "JUMPDEST-PUSH1": 15, "JUMPDEST-PUSH2": 9, "JUMPDEST-SLOAD": 2, "JUMPDEST-SWAP1": 1, "JUMPDEST-SWAP2": 1, "JUMPDEST-SWAP3": 1, "JUMPDEST-SWAP4": 1, "JUMPDEST-SWAP5": 1, "JUMPI-DUP1": 7, "JUMPI-JUMPDEST": 12, "JUMPI-PUSH1": 2, "JUMPI-PUSH2": 1, "JUMPI-RETURNDATASIZE": 1, "KECCAK256-DUP1": 1, "KECCAK256-DUP6": 1, "KECCAK256-SLOAD": 2, "LOG3-PUSH2": 1, "LT-ISZERO": 1, "LT-PUSH2": 2, "MLOAD-DUP1": 2, "MLOAD-PUSH2": 1, "MLOAD-SWAP1": 1, "MSTORE-CALLVALUE": 1, "MSTORE-PUSH1": 9, "MSTORE-SWAP1": 1, "NOT-DUP3": 1, "POP-ADD": 1, "POP-DUP2": 1, "POP-DUP3": 1, "POP-JUMP": 7, "POP-POP": 9, "POP-PUSH1": 2, "POP-SWAP1": 1, "PUSH1-ADD": 2, "PUSH1-AND": 1, "PUSH1-CALLDATALOAD": 2, "PUSH1-CALLDATASIZE": 2, "PUSH1-DUP1": 5, "PUSH1-DUP2": 1, "PUSH1-DUP3": 1, "PUSH1-DUP4": 1, "PUSH1-DUP5": 1, "PUSH1-MLOAD": 4, "PUSH1-MSTORE": 5, "PUSH1-PUSH1": 29, "PUSH1-PUSH2": 3, "PUSH1-PUSH32": 2, "PUSH1-RETURN": 1, "PUSH1-SHL": 12, "PUSH1-SHR": 2, "PUSH1-SWAP1": 4, "PUSH1-SWAP3": 1, "PUSH1-SWAP4": 1, "PUSH2-CALLDATASIZE": 1, "PUSH2-CALLER": 1, "PUSH2-DUP4": 2, "PUSH2-JUMP": 16, "PUSH2-JUMPI": 23, "PUSH2-PUSH2": 7, "PUSH2-SWAP1": 1, "PUSH2-SWAP2": 1, "PUSH32-DUP5": 1, "PUSH32-JUMPDEST": 1, "PUSH32-PUSH2": 1, "PUSH4-EQ": 7, "PUSH4-GT": 3, "RETURNDATACOPY-DUP1": 1, "RETURNDATASIZE-PUSH1": 2, "SHL-SUB": 12, "SHR-DUP1": 2, "SLOAD-DUP2": 1, "SLOAD-DUP5": 1, "SLOAD-PUSH1": 3, "SLT-ISZERO": 1, "SSTORE-POP": 1, "SSTORE-SWAP2": 1, "SUB-AND": 6, "SUB-DUP1": 1, "SUB-DUP2": 1, "SUB-DUP3": 1, "SUB-DUP4": 3, "SUB-SLT": 1, "SUB-SWAP1": 3, "SWAP1-DUP2": 4, "SWAP1-DUP5": 1, "SWAP1-ISZERO": 1, "SWAP1-JUMP": 3, "SWAP1-KECCAK256": 1, "SWAP1-LOG3": 1, "SWAP1-POP": 4, "SWAP1-PUSH2": 2, "SWAP1-RETURN": 1, "SWAP1-SSTORE": 2, "SWAP1-SWAP4": 1, "SWAP2-DUP2": 1, "SWAP2-DUP6": 1, "SWAP2-POP": 1, "SWAP2-SUB": 2, "SWAP2-SWAP1": 3, "SWAP3-POP": 2, "SWAP3-SWAP1": 1, "SWAP3-SWAP2": 1, "SWAP4-ADD": 1, "SWAP4-POP": 1, "SWAP4-SWAP1": 1, "SWAP4-SWAP3": 1, "SWAP5-PUSH1": 1 } } ``` {% endcode %}