agentmods.dev

rspack-debugging

A debugging guide for Rspack build crashes and hangs, including segmentation faults, which are serious program crashes. It uses LLDB, a debugger that can show where a program failed.

In plain words
What is it for?
Use it to prepare LLDB, install Rspack packages with debugging information, reproduce the failure, and capture automated diagnostic output.
Why use it?
It helps collect a detailed crash backtrace so developers can investigate the underlying problem instead of guessing from the visible error.

Skill for Claude CodeCodex

90 5d ago A scan 56 tokens original MIT
View the source file rstackjs/agent-skills
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/rstackjs/agent-skills/rspack-debugging
Any agent
npx skills add rstackjs/agent-skills --skill rspack-debugging
Clone the repo
git clone --depth 1 https://github.com/rstackjs/agent-skills

Made for: Claude Code, Codex.

Per session 56 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 896 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00056 $0.00896
Opus 5 $0.00028 $0.00448
Sonnet 5 $0.00011 $0.00179
Haiku 4.5 $0.00006 $0.00090

Measured 2d ago against content hash 2c5dd3c2d376, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

rspack-debugging scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/setup_debug_deps.cjs), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/rspack-debugging/SKILL.md · 93 lines

How it starts

The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Rspack Debugging

Overview

This Skill guides you on how to capture the underlying crash state of Rspack (which is based on Rust). By using the LLDB debugger and Rspack packages with debug symbols, we can obtain detailed stack backtraces, which are crucial for pinpointing issues. The guides focus on non-interactive, automated debugging to easily capture backtraces.

Preparation

Before starting, please ensure your environment meets the requirements.

  1. Install LLDB: You must install the LLDB debugger.

    • macOS: Run xcode-select --install
    • Linux: Install the lldb package (e.g., apt-get install lldb)
    • Detailed guide: references/lldb.md

  2. Replace Debug Packages: Production packages like @rspack/core have debug symbols stripped. They must be replaced with the @rspack-debug/* series packages to see useful stack information.

    Automatic Replacement Script:

    Resolve the bundled scripts/setup_debug_deps.cjs relative to the Skill root while keeping the working directory in the user's project, then run:

    node "<skill-root>/scripts/setup_debug_deps.cjs"

    Running the above script will automatically add pnpm.overrides configuration to package.json, pointing Rspack packages to their corresponding Debug versions. Afterwards, please be sure to run pnpm install to update dependencies.

Debugging Workflows

Identify your specific scenario and follow the corresponding linked guide.

Detailed Guides

Detailed Guides

Guide A: Crash during HMR

Scenario: Stable Crash/Deadlock during DevServer HMR. Read Guide: references/guide_a_hmr_crash.md

Guide B: Crash during Build

Scenario: Stable Crash/Deadlock during Build (or Unstable Build Crash that is frequent enough). Read Guide: references/guide_b_build_crash.md

Guide C: Attach to Stuck Process

Read the full file on GitHub · 93 lines

Files

What ships with it

8 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 93 lines · 56 tokens per session scan A 2c5dd3c2d376

Subscribe to this mod's changes

rspack-debugging is a skill published in the GitHub repository rstackjs/agent-skills (90 stars, last pushed 5d ago), licensed MIT. It adds 56 tokens to every session and 896 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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