Claude Code Internals Explorer

Analyze Claude Code's minified source to understand internal behavior and discover features.

Important Caveats

• Minified code: Variable names are obfuscated (e.g., UnB, cT0)
• Version-specific: Findings may change between versions
• Unofficial: Discovered features may be unsupported/unstable
• Token-intensive: Mitigated via subagent delegation (see Workflow Phase 0)

Quick Start

1. Delegate exploration to Explore subagent:

Task tool (subagent_type: Explore)
Prompt: "Run ~/.claude/skills/claude-code-internals/scripts/find_installation.sh,
        then search for [keyword] in cli.js. Report file paths and matching lines."

2. Analyze findings in main context (subagent returns summary)

3. Iterate with follow-up delegation if deeper investigation needed

Workflow

0. Delegate Context Gathering

Principle: Initial exploration consumes tokens in subagent context, preserving main context for analysis.

Call Task tool with:

• subagent_type: Explore
• prompt: Specify search target and expected output format

Example delegation:

Find Claude Code installation path using ~/.claude/skills/claude-code-internals/scripts/find_installation.sh.
Then search for patterns related to [feature] in cli.js.
Return: installation path, version, matching lines with context.

The subagent will:

1. Execute shell scripts and grep commands
2. Filter and summarize findings
3. Return structured results to main context

Main agent then performs interpretation and decision-making.

1. Locate Source

Run scripts/find_installation.sh to find:

• cli.js path (minified JavaScript source, ~9.9MB)
• Current version
• Binary location

Typical path: ~/.npm/_npx/*/node_modules/@anthropic-ai/claude-code/cli.js

2. Choose Investigation Type

3. Search Strategies

For minified code, search string literals (not variable names).

Quick example:

grep -E "anthropic-beta|context-management" cli.js

See references/search-patterns.md for comprehensive patterns by category.

4. Analyze Findings

When you find relevant code:

1. Note line numbers: grep -n "pattern" cli.js
2. Extract context: sed -n 'LINE-10,LINE+10p' cli.js
3. Trace related code by searching for adjacent strings
4. Compare with references/known-features.md

5. Document Discoveries

Update references/known-features.md with:

• New features found
• Changed defaults/thresholds
• New beta headers
• Corrected information

Common Investigations

Resources

• scripts/find_installation.sh: Locate Claude Code installation
• references/search-patterns.md: Comprehensive grep patterns by category
• references/known-features.md: Baseline of known features for comparison

Tips

1. Start narrow: Search specific terms before broad exploration
2. Use line numbers: -n flag helps locate code for context reading
3. Chain searches: Find one string, search nearby for related code
4. Save findings: Update known-features.md to track discoveries
5. Version awareness: Note version when documenting findings