Contract Decode

by sd0xdev

Contract Decode is an AI Engineering skill for Claude Code, published by sd0xdev in sd0x-dev-flow.

188 stars24 forkson sd0xdev/sd0x-dev-flowAdded 2026/09/06Repository updated 2026/09/05

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Install in seconds

Install Contract Decode

Copy Contract Decode into your Claude Code skills folder. Run the command in your terminal, or review the source on GitHub before installing.

terminal

npx degit https://github.com/sd0xdev/sd0x-harness/tree/main/skills/contract-decode ~/.claude/skills/contract-decode

Requires Node.js. Downloads this skill only — not the rest of the repository — into your Claude Code skills folder.

Without Node.js

git clone https://github.com/sd0xdev/sd0x-harness.git

Clones the whole repository, then copy the skill’s own directory into your skills folder yourself.

In this catalog

Source file: skills/contract-decode/SKILL.md in sd0xdev/sd0x-dev-flow
Installs to: ~/.claude/skills/contract-decode
Collection: One of 25 skills cataloged from this repository
Category: AI Engineering — 3278 skills

What Contract Decode does

Contract Decode decodes EVM revert data, function selectors, custom errors, and calldata from hex input. Use it when you have 0x-prefixed calldata, a selector, or an execution reverted message and need the signature or arguments.

Contract Decode is cataloged under AI Engineering on DirSkills. Contract Decode comes from a repository tagged agent-harness, claude-code, claude-code-plugin, codex and harness-engineering.

Documentation

README

Excerpt

Contract Decode — EVM Error & Calldata Decoder

Decode EVM contract function selectors, custom errors, calldata, and revert data.

Trigger

Keywords: revert, selector, 4byte, calldata, decode, custom error, execution reverted, abi decode
Message contains 0x + 8+ hex chars (selector or revert data)

When NOT to Use

Standard Error(string) revert already handled by your codebase
Non-EVM chain errors
Only need error code definitions (not hex decoding)

Input Parsing

Extract from user input:

This is the opening of the README. Read the full README on GitHub.

Frequently asked about Contract Decode

What else does sd0xdev publish alongside Contract Decode?
Contract Decode is one of 25 skills that DirSkills catalogs from sd0xdev/sd0x-dev-flow, the repository it ships in. Its siblings there include Adr, Architecture Design and Ask. Each one is a separate skill with its own page in this directory, installs the same way Contract Decode does, and is maintained by sd0xdev in that same repository. The rest of the collection is listed on the sd0xdev/sd0x-dev-flow page.
How does Contract Decode compare to other AI Engineering skills?
Contract Decode ranks #2974 by stars among the 3278 AI Engineering skills in this catalog. The most-starred ones next to it are Architecture Decision Records, AI-First Engineering and Agentic OS. DirSkills ranks by the star count of the repository each skill ships in, so that order reflects how popular those repositories are rather than any review of Contract Decode against them. Open each page to compare what they document and how they install.