diff --git a/README.md b/README.md deleted file mode 100644 index ec3a91d..0000000 --- a/README.md +++ /dev/null @@ -1,463 +0,0 @@ -# Claude Code's Entire Source Code Got Leaked via a Sourcemap in npm, Let's Talk About It - -> **PS:** I've also published this [breakdown on my blog](https://kuber.studio/blog/AI/Claude-Code's-Entire-Source-Code-Got-Leaked-via-a-Sourcemap-in-npm,-Let's-Talk-About-it) with a better reading experience and UX :) - -> There's also a non-zero chance this repo might be taken down, so if you want to play around with it later, or archive it yourself, feel free to fork it & bookmark the external blog link ! - -Earlier today (March 31st, 2026) - Chaofan Shou on X discovered something that Anthropic probably didn't want the world to see: the **entire source code** of Claude Code, Anthropic's official AI coding CLI, was sitting in plain sight on the npm registry via a sourcemap file bundled into the published package. - -[![The tweet announcing the leak](https://raw.githubusercontent.com/kuberwastaken/claude-code/main/public/leak-tweet.png)](https://raw.githubusercontent.com/kuberwastaken/claude-code/main/public/leak-tweet.png) - -This repository is a backup of that leaked source, and this README is a full breakdown of what's in it, how the leak happened and most importantly, the things we now know that were never meant to be public. - -Let's get into it. - -## How Did This Even Happen? - -This is the part that honestly made me go "...really?" - -When you publish a JavaScript/TypeScript package to npm, the build toolchain often generates **source map files** (`.map` files). These files are a bridge between the minified/bundled production code and the original source, they exist so that when something crashes in production the stack trace can point you to the *actual* line of code in the *original* file, not some unintelligible line 1, column 48293 of a minified blob. - -But the fun part is **source maps contain the original source code**. The actual, literal, raw source code, embedded as strings inside a JSON file. - -The structure of a `.map` file looks something like this: - -```json -{ - "version": 3, - "sources": ["../src/main.tsx", "../src/tools/BashTool.ts", "..."], - "sourcesContent": ["// The ENTIRE original source code of each file", "..."], - "mappings": "AAAA,SAAS,OAAO..." -} -``` - -That `sourcesContent` array? That's everything. -Every file. Every comment. Every internal constant. Every system prompt. All of it, sitting right there in a JSON file that npm happily serves to anyone who runs `npm pack` or even just browses the package contents. - -This is not a novel attack vector. It's happened before and honestly it'll happen again. - -The mistake is almost always the same: someone forgets to add `*.map` to their `.npmignore` or doesn't configure their bundler to skip source map generation for production builds. With Bun's bundler (which Claude Code uses), source maps are generated by default unless you explicitly turn them off. - -[![Claude Code source files exposed in npm package](https://raw.githubusercontent.com/kuberwastaken/claude-code/main/public/claude-files.png)](https://raw.githubusercontent.com/kuberwastaken/claude-code/main/public/claude-files.png) - -The funniest part is, there's an entire system called ["Undercover Mode"](#undercover-mode--do-not-blow-your-cover) specifically designed to prevent Anthropic's internal information from leaking. - -They built a whole subsystem to stop their AI from accidentally revealing internal codenames in git commits... and then shipped the entire source in a `.map` file, likely by Claude. - ---- - -## What's Claude Under The Hood? - -If you've been living under a rock, Claude Code is Anthropic's official CLI tool for coding with Claude and the most popular AI coding agent. - -From the outside, it looks like a polished but relatively simple CLI. - -From the inside, It's a **785KB [`main.tsx`](https://github.com/kuberwastaken/claude-code/blob/main/main.tsx)** entry point, a custom React terminal renderer, 40+ tools, a multi-agent orchestration system, a background memory consolidation engine called "dream," and much more - -Enough yapping, here's some parts about the source code that are genuinely cool that I found after an afternoon deep dive: - ---- - -## BUDDY - A Tamagotchi Inside Your Terminal - -I am not making this up. - -Claude Code has a full **Tamagotchi-style companion pet system** called "Buddy." A **deterministic gacha system** with species rarity, shiny variants, procedurally generated stats, and a soul description written by Claude on first hatch like OpenClaw. - -The entire thing lives in [`buddy/`](https://github.com/kuberwastaken/claude-code/tree/main/buddy) and is gated behind the `BUDDY` compile-time feature flag. - -### The Gacha System - -Your buddy's species is determined by a **Mulberry32 PRNG**, a fast 32-bit pseudo-random number generator seeded from your `userId` hash with the salt `'friend-2026-401'`: - -```typescript -// Mulberry32 PRNG - deterministic, reproducible per-user -function mulberry32(seed: number): () => number { - return function() { - seed |= 0; seed = seed + 0x6D2B79F5 | 0; - var t = Math.imul(seed ^ seed >>> 15, 1 | seed); - t = t + Math.imul(t ^ t >>> 7, 61 | t) ^ t; - return ((t ^ t >>> 14) >>> 0) / 4294967296; - } -} -``` - -Same user always gets the same buddy. - -### 18 Species (Obfuscated in Code) - -The species names are hidden via `String.fromCharCode()` arrays - Anthropic clearly didn't want these showing up in string searches. Decoded, the full species list is: - -| Rarity | Species | -|--------|---------| -| **Common** (60%) | Pebblecrab, Dustbunny, Mossfrog, Twigling, Dewdrop, Puddlefish | -| **Uncommon** (25%) | Cloudferret, Gustowl, Bramblebear, Thornfox | -| **Rare** (10%) | Crystaldrake, Deepstag, Lavapup | -| **Epic** (4%) | Stormwyrm, Voidcat, Aetherling | -| **Legendary** (1%) | Cosmoshale, Nebulynx | - -On top of that, there's a **1% shiny chance** completely independent of rarity. So a Shiny Legendary Nebulynx has a **0.01%** chance of being rolled. Dang. - -### Stats, Eyes, Hats, and Soul - -Each buddy gets procedurally generated: -- **5 stats**: `DEBUGGING`, `PATIENCE`, `CHAOS`, `WISDOM`, `SNARK` (0-100 each) -- **6 possible eye styles** and **8 hat options** (some gated by rarity) -- **A "soul"** as mentioned, the personality generated by Claude on first hatch, written in character - -The sprites are rendered as **5-line-tall, 12-character-wide ASCII art** with multiple animation frames. There are idle animations, reaction animations, and they sit next to your input prompt. - -### The Lore - -The code references April 1-7, 2026 as a **teaser window** (so probably for easter?), with a full launch gated for May 2026. The companion has a system prompt that tells Claude: - -``` -A small {species} named {name} sits beside the user's input box and -occasionally comments in a speech bubble. You're not {name} - it's a -separate watcher. -``` - -So it's not just cosmetic - the buddy has its own personality and can respond when addressed by name. I really do hope they ship it. - ---- - -## KAIROS - "Always-On Claude" - -Inside [`assistant/`](https://github.com/kuberwastaken/claude-code/tree/main/assistant), there's an entire mode called **KAIROS** i.e. a persistent, always-running Claude assistant that doesn't wait for you to type. It watches, logs, and **proactively** acts on things it notices. - -This is gated behind the `PROACTIVE` / `KAIROS` compile-time feature flags and is completely absent from external builds. - -### How It Works - -KAIROS maintains **append-only daily log files** - it writes observations, decisions, and actions throughout the day. On a regular interval, it receives `` prompts that let it decide whether to act proactively or stay quiet. - -The system has a **15-second blocking budget**, any proactive action that would block the user's workflow for more than 15 seconds gets deferred. This is Claude trying to be helpful without being annoying. - -### Brief Mode - -When KAIROS is active, there's a special output mode called **Brief**, extremely concise responses designed for a persistent assistant that shouldn't flood your terminal. Think of it as the difference between a chatty friend and a professional assistant who only speaks when they have something valuable to say. - -### Exclusive Tools - -KAIROS gets tools that regular Claude Code doesn't have: - -| Tool | What It Does | -|------|-------------| -| **SendUserFile** | Push files directly to the user (notifications, summaries) | -| **PushNotification** | Send push notifications to the user's device | -| **SubscribePR** | Subscribe to and monitor pull request activity | - - --- - -## ULTRAPLAN - 30-Minute Remote Planning Sessions - -Here's one that's wild from an infrastructure perspective. - -**ULTRAPLAN** is a mode where Claude Code offloads a complex planning task to a **remote Cloud Container Runtime (CCR) session** running **Opus 4.6**, gives it up to **30 minutes** to think, and lets you approve the result from your browser. - -The basic flow: - -1. Claude Code identifies a task that needs deep planning -2. It spins up a remote CCR session via the `tengu_ultraplan_model` config -3. Your terminal shows a polling state - checking every **3 seconds** for the result -4. Meanwhile, a browser-based UI lets you watch the planning happen and approve/reject it -5. When approved, there's a special sentinel value `__ULTRAPLAN_TELEPORT_LOCAL__` that "teleports" the result back to your local terminal - ---- - -## The "Dream" System - Claude Literally Dreams - -Okay this is genuinely one of the coolest things in here. - -Claude Code has a system called **autoDream** ([`services/autoDream/`](https://github.com/kuberwastaken/claude-code/tree/main/services/autoDream)) - a background memory consolidation engine that runs as a **forked subagent**. The naming is very intentional. It's Claude... dreaming. - -This is extremely funny because [I had the same idea for LITMUS last week - OpenClaw subagents creatively having leisure time to find fun new papers](https://github.com/Kuberwastaken/litmus) - -### The Three-Gate Trigger - -The dream doesn't just run whenever it feels like it. It has a **three-gate trigger system**: - -1. **Time gate**: 24 hours since last dream -2. **Session gate**: At least 5 sessions since last dream -3. **Lock gate**: Acquires a consolidation lock (prevents concurrent dreams) - -All three must pass. This prevents both over-dreaming and under-dreaming. - -### The Four Phases - -When it runs, the dream follows four strict phases from the prompt in [`consolidationPrompt.ts`](https://github.com/kuberwastaken/claude-code/blob/main/services/autoDream/consolidationPrompt.ts): - -**Phase 1 - Orient**: `ls` the memory directory, read `MEMORY.md`, skim existing topic files to improve. - -**Phase 2 - Gather Recent Signal**: Find new information worth persisting. Sources in priority: daily logs → drifted memories → transcript search. - -**Phase 3 - Consolidate**: Write or update memory files. Convert relative dates to absolute. Delete contradicted facts. - -**Phase 4 - Prune and Index**: Keep `MEMORY.md` under 200 lines AND ~25KB. Remove stale pointers. Resolve contradictions. - -The prompt literally says: - -> *"You are performing a dream - a reflective pass over your memory files. Synthesize what you've learned recently into durable, well-organized memories so that future sessions can orient quickly."* - -The dream subagent gets **read-only bash** - it can look at your project but not modify anything. It's purely a memory consolidation pass. - ---- - -## Undercover Mode - "Do Not Blow Your Cover" - - -This one is fascinating from a corporate strategy perspective. - -Anthropic employees (identified by `USER_TYPE === 'ant'`) use Claude Code on public/open-source repositories. **Undercover Mode** ([`utils/undercover.ts`](https://github.com/kuberwastaken/claude-code/blob/main/utils/undercover.ts)) prevents the AI from accidentally revealing internal information in commits and PRs. - -When active, it injects this into the system prompt: - -``` -## UNDERCOVER MODE - CRITICAL - -You are operating UNDERCOVER in a PUBLIC/OPEN-SOURCE repository. Your commit -messages, PR titles, and PR bodies MUST NOT contain ANY Anthropic-internal -information. Do not blow your cover. - -NEVER include in commit messages or PR descriptions: -- Internal model codenames (animal names like Capybara, Tengu, etc.) -- Unreleased model version numbers (e.g., opus-4-7, sonnet-4-8) -- Internal repo or project names -- Internal tooling, Slack channels, or short links (e.g., go/cc, #claude-code-…) -- The phrase "Claude Code" or any mention that you are an AI -- Co-Authored-By lines or any other attribution -``` - -The activation logic: -- `CLAUDE_CODE_UNDERCOVER=1` forces it ON (even in internal repos) -- Otherwise it's **automatic**: active UNLESS the repo remote matches an internal allowlist -- There is **NO force-OFF** - *"if we're not confident we're in an internal repo, we stay undercover."* - -So this confirms: -1. **Anthropic employees actively use Claude Code to contribute to open-source** - and the AI is told to hide that it's an AI -2. **Internal model codenames are animal names** - Capybara, Tengu, etc. -3. **"Tengu"** appears hundreds of times as a prefix for feature flags and analytics events - it's almost certainly **Claude Code's internal project codename** - -All of this is dead-code-eliminated from external builds. But source maps don't care about dead code elimination. - -Makes me wonder how much are they internally causing havoc to open source repos - ---- - -## Multi-Agent Orchestration - "Coordinator Mode" - - -Claude Code has a full **multi-agent orchestration system** in [`coordinator/`](https://github.com/kuberwastaken/claude-code/tree/main/coordinator), activated via `CLAUDE_CODE_COORDINATOR_MODE=1`. - -When enabled, Claude Code transforms from a single agent into a **coordinator** that spawns, directs, and manages multiple worker agents in parallel. The coordinator system prompt in [`coordinatorMode.ts`](https://github.com/kuberwastaken/claude-code/blob/main/coordinator/coordinatorMode.ts) is a masterclass in multi-agent design: - -| Phase | Who | Purpose | -|-------|-----|---------| -| **Research** | Workers (parallel) | Investigate codebase, find files, understand problem | -| **Synthesis** | **Coordinator** | Read findings, understand the problem, craft specs | -| **Implementation** | Workers | Make targeted changes per spec, commit | -| **Verification** | Workers | Test changes work | - -The prompt **explicitly** teaches parallelism: - -> *"Parallelism is your superpower. Workers are async. Launch independent workers concurrently whenever possible - don't serialize work that can run simultaneously."* - -Workers communicate via `` XML messages. There's a shared **scratchpad directory** (gated behind `tengu_scratch`) for cross-worker durable knowledge sharing. And the prompt has this gem banning lazy delegation: - -> *Do NOT say "based on your findings" - read the actual findings and specify exactly what to do.* - -The system also includes **Agent Teams/Swarm** capabilities (`tengu_amber_flint` feature gate) with in-process teammates using `AsyncLocalStorage` for context isolation, process-based teammates using tmux/iTerm2 panes, team memory synchronization, and color assignments for visual distinction. - ---- - -## Fast Mode is Internally Called "Penguin Mode" - -Yeah, they really called it Penguin Mode. The API endpoint in [`utils/fastMode.ts`](https://github.com/kuberwastaken/claude-code/blob/main/utils/fastMode.ts) is literally: - -```typescript -const endpoint = `${getOauthConfig().BASE_API_URL}/api/claude_code_penguin_mode` -``` - -The config key is `penguinModeOrgEnabled`. The kill-switch is `tengu_penguins_off`. The analytics event on failure is `tengu_org_penguin_mode_fetch_failed`. Penguins all the way down. - ---- - -## The System Prompt Architecture - -The system prompt isn't a single string like most apps have - it's built from **modular, cached sections** composed at runtime in [`constants/`](https://github.com/kuberwastaken/claude-code/tree/main/constants). - -The architecture uses a `SYSTEM_PROMPT_DYNAMIC_BOUNDARY` marker that splits the prompt into: -- **Static sections** - cacheable across organizations (things that don't change per user) -- **Dynamic sections** - user/session-specific content that breaks cache when changed - -There's a function called `DANGEROUS_uncachedSystemPromptSection()` for volatile sections you explicitly want to break cache. The naming convention alone tells you someone learned this lesson the hard way. - -### The Cyber Risk Instruction - -One particularly interesting section is the `CYBER_RISK_INSTRUCTION` in [`constants/cyberRiskInstruction.ts`](https://github.com/kuberwastaken/claude-code/blob/main/constants/cyberRiskInstruction.ts), which has a massive warning header: - -``` -IMPORTANT: DO NOT MODIFY THIS INSTRUCTION WITHOUT SAFEGUARDS TEAM REVIEW -This instruction is owned by the Safeguards team (David Forsythe, Kyla Guru) -``` - -So now we know exactly who at Anthropic owns the security boundary decisions and that it's governed by named individuals on a specific team. The instruction itself draws clear lines: authorized security testing is fine, destructive techniques and supply chain compromise are not. - ---- - -## The Full Tool Registry - 40+ Tools - -Claude Code's tool system lives in [`tools/`](https://github.com/kuberwastaken/claude-code/tree/main/tools).Here's the complete list: - -| Tool | What It Does | -|------|-------------| -| **AgentTool** | Spawn child agents/subagents | -| **BashTool** / **PowerShellTool** | Shell execution (with optional sandboxing) | -| **FileReadTool** / **FileEditTool** / **FileWriteTool** | File operations | -| **GlobTool** / **GrepTool** | File search (uses native `bfs`/`ugrep` when available) | -| **WebFetchTool** / **WebSearchTool** / **WebBrowserTool** | Web access | -| **NotebookEditTool** | Jupyter notebook editing | -| **SkillTool** | Invoke user-defined skills | -| **REPLTool** | Interactive VM shell (bare mode) | -| **LSPTool** | Language Server Protocol communication | -| **AskUserQuestionTool** | Prompt user for input | -| **EnterPlanModeTool** / **ExitPlanModeV2Tool** | Plan mode control | -| **BriefTool** | Upload/summarize files to claude.ai | -| **SendMessageTool** / **TeamCreateTool** / **TeamDeleteTool** | Agent swarm management | -| **TaskCreateTool** / **TaskGetTool** / **TaskListTool** / **TaskUpdateTool** / **TaskOutputTool** / **TaskStopTool** | Background task management | -| **TodoWriteTool** | Write todos (legacy) | -| **ListMcpResourcesTool** / **ReadMcpResourceTool** | MCP resource access | -| **SleepTool** | Async delays | -| **SnipTool** | History snippet extraction | -| **ToolSearchTool** | Tool discovery | -| **ListPeersTool** | List peer agents (UDS inbox) | -| **MonitorTool** | Monitor MCP servers | -| **EnterWorktreeTool** / **ExitWorktreeTool** | Git worktree management | -| **ScheduleCronTool** | Schedule cron jobs | -| **RemoteTriggerTool** | Trigger remote agents | -| **WorkflowTool** | Execute workflow scripts | -| **ConfigTool** | Modify settings (**internal only**) | -| **TungstenTool** | Advanced features (**internal only**) | -| **SendUserFile** / **PushNotification** / **SubscribePR** | KAIROS-exclusive tools | - -Tools are registered via `getAllBaseTools()` and filtered by feature gates, user type, environment flags, and permission deny rules. There's a **tool schema cache** ([`toolSchemaCache.ts`](https://github.com/kuberwastaken/claude-code/blob/main/tools/toolSchemaCache.ts)) that caches JSON schemas for prompt efficiency. - ---- - -## The Permission and Security System - -Claude Code's permission system in [`tools/permissions/`](https://github.com/kuberwastaken/claude-code/tree/main/tools/permissions) is far more sophisticated than "allow/deny": - -**Permission Modes**: `default` (interactive prompts), `auto` (ML-based auto-approval via transcript classifier), `bypass` (skip checks), `yolo` (deny all - ironically named) - -**Risk Classification**: Every tool action is classified as **LOW**, **MEDIUM**, or **HIGH** risk. There's a **YOLO classifier** - a fast ML-based permission decision system that decides automatically. - -**Protected Files**: `.gitconfig`, `.bashrc`, `.zshrc`, `.mcp.json`, `.claude.json` and others are guarded from automatic editing. - -**Path Traversal Prevention**: URL-encoded traversals, Unicode normalization attacks, backslash injection, case-insensitive path manipulation - all handled. - -**Permission Explainer**: A separate LLM call explains tool risks to the user before they approve. When Claude says "this command will modify your git config" - that explanation is itself generated by Claude. - ---- - -## Hidden Beta Headers and Unreleased API Features - -The [`constants/betas.ts`](https://github.com/kuberwastaken/claude-code/blob/main/constants/betas.ts) file reveals every beta feature Claude Code negotiates with the API: - -```typescript -'interleaved-thinking-2025-05-14' // Extended thinking -'context-1m-2025-08-07' // 1M token context window -'structured-outputs-2025-12-15' // Structured output format -'web-search-2025-03-05' // Web search -'advanced-tool-use-2025-11-20' // Advanced tool use -'effort-2025-11-24' // Effort level control -'task-budgets-2026-03-13' // Task budget management -'prompt-caching-scope-2026-01-05' // Prompt cache scoping -'fast-mode-2026-02-01' // Fast mode (Penguin) -'redact-thinking-2026-02-12' // Redacted thinking -'token-efficient-tools-2026-03-28' // Token-efficient tool schemas -'afk-mode-2026-01-31' // AFK mode -'cli-internal-2026-02-09' // Internal-only (ant) -'advisor-tool-2026-03-01' // Advisor tool -'summarize-connector-text-2026-03-13' // Connector text summarization -``` - -`redact-thinking`, `afk-mode`, and `advisor-tool` are also not released. - ---- - -## Feature Gating - Internal vs. External Builds - -This is one of the most architecturally interesting parts of the codebase. - -Claude Code uses **compile-time feature flags** via Bun's `feature()` function from `bun:bundle`. The bundler **constant-folds** these and **dead-code-eliminates** the gated branches from external builds. The complete list of known flags: - -| Flag | What It Gates | -|------|--------------| -| `PROACTIVE` / `KAIROS` | Always-on assistant mode | -| `KAIROS_BRIEF` | Brief command | -| `BRIDGE_MODE` | Remote control via claude.ai | -| `DAEMON` | Background daemon mode | -| `VOICE_MODE` | Voice input | -| `WORKFLOW_SCRIPTS` | Workflow automation | -| `COORDINATOR_MODE` | Multi-agent orchestration | -| `TRANSCRIPT_CLASSIFIER` | AFK mode (ML auto-approval) | -| `BUDDY` | Companion pet system | -| `NATIVE_CLIENT_ATTESTATION` | Client attestation | -| `HISTORY_SNIP` | History snipping | -| `EXPERIMENTAL_SKILL_SEARCH` | Skill discovery | - -Additionally, `USER_TYPE === 'ant'` gates Anthropic-internal features: staging API access (`claude-ai.staging.ant.dev`), internal beta headers, Undercover mode, the `/security-review` command, `ConfigTool`, `TungstenTool`, and debug prompt dumping to `~/.config/claude/dump-prompts/`. - -**GrowthBook** handles runtime feature gating with aggressively cached values. Feature flags prefixed with `tengu_` control everything from fast mode to memory consolidation. Many checks use `getFeatureValue_CACHED_MAY_BE_STALE()` to avoid blocking the main loop - stale data is considered acceptable for feature gates. - ---- - -## Other Notable Findings - -### The Upstream Proxy -The [`upstreamproxy/`](https://github.com/kuberwastaken/claude-code/tree/main/upstreamproxy) directory contains a container-aware proxy relay that uses **`prctl(PR_SET_DUMPABLE, 0)`** to prevent same-UID ptrace of heap memory. It reads session tokens from `/run/ccr/session_token` in CCR containers, downloads CA certificates, and starts a local CONNECT→WebSocket relay. Anthropic API, GitHub, npmjs.org, and pypi.org are explicitly excluded from proxying. - -### Bridge Mode -A JWT-authenticated bridge system in [`bridge/`](https://github.com/kuberwastaken/claude-code/tree/main/bridge) for integrating with claude.ai. Supports work modes: `'single-session'` | `'worktree'` | `'same-dir'`. Includes trusted device tokens for elevated security tiers. - -### Model Codenames in Migrations -The [`migrations/`](https://github.com/kuberwastaken/claude-code/tree/main/migrations) directory reveals the internal codename history: -- `migrateFennecToOpus` - **"Fennec"** (the fox) was an Opus codename -- `migrateSonnet1mToSonnet45` - Sonnet with 1M context became Sonnet 4.5 -- `migrateSonnet45ToSonnet46` - Sonnet 4.5 → Sonnet 4.6 -- `resetProToOpusDefault` - Pro users were reset to Opus at some point - -### Attribution Header -Every API request includes: -``` -x-anthropic-billing-header: cc_version={VERSION}.{FINGERPRINT}; - cc_entrypoint={ENTRYPOINT}; cch={ATTESTATION_PLACEHOLDER}; cc_workload={WORKLOAD}; -``` -The `NATIVE_CLIENT_ATTESTATION` feature lets Bun's HTTP stack overwrite the `cch=00000` placeholder with a computed hash - essentially a client authenticity check so Anthropic can verify the request came from a real Claude Code install. - -### Computer Use - "Chicago" -Claude Code includes a full Computer Use implementation, internally codenamed **"Chicago"**, built on `@ant/computer-use-mcp`. It provides screenshot capture, click/keyboard input, and coordinate transformation. Gated to Max/Pro subscriptions (with an ant bypass for internal users). - -### Pricing -For anyone wondering - all pricing in [`utils/modelCost.ts`](https://github.com/kuberwastaken/claude-code/blob/main/utils/modelCost.ts) matches [Anthropic's public pricing](https://docs.anthropic.com/en/docs/about-claude/models) exactly. Nothing newsworthy there. - ---- - -## Final Thoughts - -This is, without exaggeration, one of the most comprehensive looks we've ever gotten at how *the* production AI coding assistant works under the hood. Through the actual source code. - -A few things stand out: - -**The engineering is genuinely impressive.** This isn't a weekend project wrapped in a CLI. The multi-agent coordination, the dream system, the three-gate trigger architecture, the compile-time feature elimination - these are deeply considered systems. - -**There's a LOT more coming.** KAIROS (always-on Claude), ULTRAPLAN (30-minute remote planning), the Buddy companion, coordinator mode, agent swarms, workflow scripts - the codebase is significantly ahead of the public release. Most of these are feature-gated and invisible in external builds. - -**The internal culture shows.** Animal codenames (Tengu, Fennec, Capybara), playful feature names (Penguin Mode, Dream System), a Tamagotchi pet system with gacha mechanics. Some people at Anthropic is having fun. - -If there's one takeaway this has, it's that security is hard. But `.npmignore` is harder, apparently :P - ---- - -A writeup by [Kuber Mehta](https://kuber.studio/) \ No newline at end of file