Documentation Index Fetch the complete documentation index at: https://cofhe-docs.fhenix.zone/llms.txt
Use this file to discover all available pages before exploring further.
Overview When working with Solidity smart contracts, you’ve probably encountered cryptic error messages like:
Error: execution reverted: 0x118cdaa7 Transaction reverted without a reason string execution reverted
These errors are frustrating because you only get a 4-byte error selector (e.g., 0x118cdaa7) with no human-readable message. The @fhenixprotocol/cofhe-errors package provides instant, human-readable error decoding for CoFHE smart contracts.
What's Inside
53 custom errors from 13 smart contracts Complete error signatures with parameter types
Source contract information
Fast CLI lookup tool
Programmatic JavaScript/TypeScript API
Quick Start No installation required! Use npx to decode errors immediately:npx cofhe-errors 0x118cdaa7
Output: Name: OwnableUnauthorizedAccount Selector: 0x118cdaa7 Signature: OwnableUnauthorizedAccount(address) Source: ACL Inputs: address
Installation (Optional) Only install if you need to import the error database programmatically in your code:
npm install @fhenixprotocol/cofhe-errors
CLI Usage Decode an Error Selector When you see “execution reverted: 0x…”, decode it instantly:
npx cofhe-errors 0x118cdaa7
Search Errors by Name Find errors when you know part of the error name:
npx cofhe-errors --name Permission
Output: 0x4c40eccb PermissionInvalid_IssuerSignature (ACL) 0x8e143bf7 PermissionInvalid_RecipientSignature (ACL) 0xcbd3a966 PermissionInvalid_Disabled (ACL) 0xed0764a1 PermissionInvalid_Expired (ACL)
List All Known Errors Browse the complete error database:
JSON Output Get JSON output for scripting and automation:
npx cofhe-errors --json 0x118cdaa7
Output: { "name" : "OwnableUnauthorizedAccount" , "selector" : "0x118cdaa7" , "signature" : "OwnableUnauthorizedAccount(address)" , "source" : "ACL" , "inputs" : [ "account" ], "inputTypes" : [ "address" ] }
Programmatic API JavaScript/TypeScript Usage const errors = require ( '@fhenixprotocol/cofhe-errors/errors.json' ); // Find error by selector const error = errors . find ( e => e . selector === '0x118cdaa7' ); console . log ( `Error: ${ error . name } ` ); console . log ( `Signature: ${ error . signature } ` ); // Search by name const permissionErrors = errors . filter ( e => e . name . toLowerCase (). includes ( 'permission' ) ); // Get all errors from a specific contract const aclErrors = errors . filter ( e => e . source === 'ACL' );
TypeScript with Types import errors from '@fhenixprotocol/cofhe-errors/errors.json' ; interface SolidityError { name : string ; selector : string ; signature : string ; source : string ; inputs : string []; inputTypes : string []; } const error = errors . find ( e => e . selector === '0x118cdaa7' ) as SolidityError ;
Error Monitoring Example const errors = require ( '@fhenixprotocol/cofhe-errors/errors.json' ); // Decode error from blockchain event function decodeError ( errorData ) { const selector = errorData . slice ( 0 , 10 ); // First 4 bytes const error = errors . find ( e => e . selector === selector ); if ( error ) { console . log ( `Error: ${ error . name } ` ); console . log ( `Contract: ${ error . source } ` ); console . log ( `Signature: ${ error . signature } ` ); } }
Error Coverage The package includes errors from the following contracts:
Contract Error Count TaskManager 16 ACL 8 SafeCast 4 ERC1967Utils 4 Errors 4 Ownable2StepUpgradeable 4 ECDSA 3 Strings 3 Common 2 UUPSUpgradeable 2 Address 1 FHE 1 PlaintextsStorage 1
How Error Selectors Work Solidity custom errors use a 4-byte selector computed as:
selector = keccak256("ErrorName(type1,type2,...)").slice(0, 4)
Example: error OwnableUnauthorizedAccount ( address account);
Becomes:
Signature: OwnableUnauthorizedAccount(address)
Selector: keccak256("OwnableUnauthorizedAccount(address)") = 0x118cdaa7...
First 4 bytes: 0x118cdaa7
Next Steps 
