Claude Code Research
Description
Independent research on Claude Code internals, Claude Agent SDK, and related tooling.
Installation
This entry records only its repository, not the path inside it, so there is no
exact command to give. Open the source below and copy the folder into
~/.claude/skills/, or the file into ~/.claude/agents/.
README
Claude Code Research
[](./CONTRIBUTING.md)
Independent research on Claude Code internals.
What's in this repo
| Directory | What | Source | Count |
|---|---|---|---|
| `source-code-analysis/` | Full architecture reverse-engineering | Leaked TypeScript source (v2.1.88) | 75 reports |
| `reports/` | Problem-oriented investigations (cache, cost, injection) | Minified npm bundle (cli.js) |
8 reports |
**Looking for the source code analysis?** Go to [`source-code-analysis/`](./source-code-analysis/). **Looking for specific bug/cost investigations?** Go to [`reports/`](./reports/).
Source Code Analysis (`source-code-analysis/`)
On 2026-03-31, the full source code of Claude Code was exposed via a sourcemap file in the npm registry ([discovered by Chaofan Shou](https://x.com/shoucccc), archived by [Kuberwastaken](https://github.com/Kuberwastaken/claude-code) and [sanbuphy](https://github.com/sanbuphy/claude-code-source-code)).
We performed a 10-domain, 75-report analysis — the most thorough publicly available breakdown of how a production AI coding agent works.
**[Browse all reports →](./source-code-analysis/)**
Interactive viewer — open `source-code-analysis/index.html` in your browser (all 75 reports are embedded, no server needed).
Key Findings
| Domain | Reports | Highlights |
|---|---|---|
| Harness Engineering ⭐ | 7 | Agent Loop reverse-engineering, 12 transferable harness design principles |
| System Prompt ⭐ | 6 | Complete 13-section prompt with dynamic assembly logic, 17 prompt engineering patterns |
| Cost & Quota ⭐ | 8 | Cost envelope, prompt cache break detection (12 causes), Haiku→Opus 37.5x cost ga |
Related Skills
Auto Update
Pull the latest ECC repo changes and reinstall the current managed targets.
Ecc Guide
Navigate ECC's current agents, skills, commands, hooks, install profiles, and docs from the live repository su
Epic Claim
Claim an epic issue, stamp coordination state, and sync local ownership.
Epic Publish
Publish a validated epic update back to the issue and local cache.
Epic Review
Mark epic review requested, approved, or changes requested.
Epic Unblock
Sweep blocked epic issues and reopen anything whose dependencies are closed.