How do I install the Trace Tx skill?

Run npx skillmds@latest add syjcnss/trace-tx in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Trace Tx safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Trace Tx?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Trace Tx free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Trace Tx?

syjcnss (@syjcnss) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Trace Tx by syjcnss — Agent Skill

Name: Trace Tx
Author: syjcnss

Trace Tx

Fetches the full execution trace of an EVM transaction using debug_traceTransaction API. Use this skill whenever the user wants to trace a transaction, inspect internal calls, debug a failed tx, check sub-calls or revert reasons, analyze gas usage per call, understand what a transaction actually did on-chain, or investigate MEV / sandwich attacks. Trigger even if the user just says things like "trace this tx", "what did this transaction do?", "why did this tx revert?", "show me the call tree", or "get the internal calls for 0x...".

syjcnss 0f23e0a 4 files · 11.1 KB Updated Sep 17, 2026

File contents

trace-tx

Fetches the full execution trace for an EVM transaction via debug_traceTransaction. The trace reveals the complete call tree: every internal CALL/DELEGATECALL/CREATE, gas consumed at each step, input/output data, and any revert reasons.

Usage

~/.claude/skills/trace-tx/scripts/trace_tx.sh [-o <output_file>] <TX_HASH> <RPC_URL> [TRACER] [onlyTopCall]

Use the RPC URL the user supplied.
Or if ALCHEMY_API_KEY is set, construct the Alchemy URL: https://<chain-slug>.g.alchemy.com/v2/$ALCHEMY_API_KEY and use it as the RPC URL. Common slugs: "Ethereum"/"ETH" → eth-mainnet, "Arbitrum"/"Arb" → arb-mainnet, "Base" → base-mainnet, "Optimism"/"OP" → opt-mainnet, "Polygon"/"MATIC" → polygon-mainnet, "BSC"/"BNB Chain" → bnb-mainnet, "Sepolia" → eth-sepolia. Find full slug list in references/rpc_urls.md only when necessary.
If neither is available, find an RPC URL that supports debug_traceTransaction for the specific tx.
Default tracer: callTracer (nested call tree — best for most tasks). Also supports prestateTracer and raw opcode trace.

Workflow

Use -o to write the trace to a file — traces can be megabytes:

~/.claude/skills/trace-tx/scripts/trace_tx.sh -o trace_0xabc123.json 0xabc... https://your-rpc-url

Tell the user the path to the saved file.

Reference

Full RPC URL list: references/rpc_urls.md

---name: trace-txdescription: Fetches the full execution trace of an EVM transaction using debug_traceTransaction API. Use this skill whenever the user wants to trace a transaction, inspect internal calls, debug a failed tx, check sub-calls or revert reasons, analyze gas usage per call, understand what a transaction actually did on-chain, or investigate MEV / sandwich attacks. Trigger even if the user just says things like "trace this tx", "what did this transaction do?", "why did this tx revert?", "show me the call tree", or "get the internal calls for 0x...".---# trace-txFetches the full execution trace for an EVM transaction via `debug_traceTransaction`. The trace reveals the complete call tree: every internal CALL/DELEGATECALL/CREATE, gas consumed at each step, input/output data, and any revert reasons.## Usage```bash~/.claude/skills/trace-tx/scripts/trace_tx.sh [-o <output_file>] <TX_HASH> <RPC_URL> [TRACER] [onlyTopCall]```- Use the RPC URL the user supplied.- Or if `ALCHEMY_API_KEY` is set, construct the Alchemy URL: `https://<chain-slug>.g.alchemy.com/v2/$ALCHEMY_API_KEY` and use it as the RPC URL. Common slugs: "Ethereum"/"ETH" → `eth-mainnet`, "Arbitrum"/"Arb" → `arb-mainnet`, "Base" → `base-mainnet`, "Optimism"/"OP" → `opt-mainnet`, "Polygon"/"MATIC" → `polygon-mainnet`, "BSC"/"BNB Chain" → `bnb-mainnet`, "Sepolia" → `eth-sepolia`. Find full slug list in `references/rpc_urls.md` only when necessary.- If neither is available, find an RPC URL that supports `debug_traceTransaction` for the specific tx.- Default tracer: `callTracer` (nested call tree — best for most tasks). Also supports `prestateTracer` and raw opcode trace.## WorkflowUse `-o` to write the trace to a file — traces can be megabytes:```bash~/.claude/skills/trace-tx/scripts/trace_tx.sh -o trace_0xabc123.json 0xabc... https://your-rpc-url```Tell the user the path to the saved file.## Reference- Full RPC URL list: `references/rpc_urls.md`

Frequently asked questions