tokenlean

57 CLI tools + MCP server that let AI agents understand codebases without burning tokens

Why • Install • Quick Reference • All Tools • AI Integration • Workflows • Languages

Zero config — npm i -g tokenlean and you're done · Token-conscious — every tool outputs only what's needed · Fast — ripgrep-powered with disk caching · Multi-language — JS/TS, Python, Go, Rust, Ruby · MCP native — structured tool access, no shell overhead · Minimal deps — installs in seconds

The Problem

If you've ever checked your usage quota at 2 PM and decided whether to debug now or wait for the reset — this is for you. Enterprise teams with unlimited API keys don't feel the burn. Solo devs, small teams, anyone on a Pro subscription does. Every cat of a 2000-line file when you needed one function, every 300-line test run when only 3 lines failed, every full directory read to find a signature — that's your working day getting shorter.

tokenlean fixes this:

Instead of...	Use	Savings
Reading a 500-line file for signatures	`tl-symbols`	~90% fewer tokens
Reading all files to find exports	`tl-exports`	~95% fewer tokens
Guessing what a change might break	`tl-impact`	Know for sure
Reading a file to extract one function	`tl-snippet`	~85% fewer tokens
Running `npm test` and reading all output	`tl-run "npm test"`	Errors only
Scanning long logs for real failures	`tl-tail app.log`	Errors/warns + dedupe

How much are you wasting?

Find out in one command, no install needed:

npx tokenlean audit --all --savings --claudecode

Summary (348 Claude Code sessions)
  Opportunities:
  Category                Count  Actual     Saveable   Suggestion
  ----------------------------------------------------------------------------
  read-large-file          75x    253.4k      202.7k   -> tl-symbols + tl-snippet
  build-test-output        34x     28.2k       18.3k   -> tl-run
  grep-command            115x     59.6k       11.9k   -> Grep tool
  tail-command              7x      4.8k        3.3k   -> tl-tail
  find-command             25x      8.6k        2.6k   -> Glob tool
  curl-command             13x      3.2k        2.3k   -> tl-browse
  cat-large-file            1x      1.1k         902   -> tl-symbols + tl-snippet
  webfetch                  4x      1.2k         823   -> tl-browse
  head-command             11x      3.8k         759   -> Read tool (with limit)

  Still saveable:     243.6k of 363.9k (67%)

  Already saved by tokenlean:
  Tool              Count  Compressed   Raw estimate   Saved
  ------------------------------------------------------------------
  tl-snippet          233x      215.7k            2.2M   1.9M
  tl-symbols           93x       59.0k          295.0k   236.0k
  tl-run               98x       28.7k           82.0k   53.3k

  Tokens saved:       2.2M (424 uses)
  Capture rate:       90% of potential savings realized

Install

npm install -g tokenlean

Requires Node.js >= 18, ripgrep for search tools, and git for history tools.

Use tl as the global entry point for discovery and health checks:

tl          # List available tokenlean commands and tools
tl doctor   # Verify Node.js, ripgrep, git, hooks, and config
tl update   # Update the global tokenlean install

Development setup

git clone https://github.com/edimuj/tokenlean.git
cd tokenlean
npm link

Quick Reference

# What's in this file?           tl-symbols src/auth.ts
# Functions only (dir/multi-file) tl-symbols src/ --filter function
# Extract just one function      tl-snippet handleSubmit
# What does this module export?  tl-exports src/lib/
# How many tokens will this cost? tl-context src/api/
# What's the project shape?      tl-structure

# What depends on this file?     tl-impact src/auth.ts
# How complex is this code?      tl-complexity src/auth.ts
# Where are the tests?           tl-related src/Button.tsx

# What changed recently?         tl-diff --staged
# Is it safe to commit?          tl-guard
# Find real usage examples       tl-example useAuth
# Summarize noisy logs            tl-tail logs/app.log
# What's the tech stack?         tl-stack

Every tool supports -l N (limit lines), -t N (limit tokens), -j (JSON output), -q (quiet), and -h (help).

AI Agent Integration

Add tokenlean instructions to your AI tool's config with a single command:

AI Tool	Command
Claude Code	`tl-prompt >> CLAUDE.md`
Codex	`tl-prompt --codex >> AGENTS.md`
Cursor	`tl-prompt --minimal >> .cursorrules`
GitHub Copilot	`tl-prompt >> .github/copilot-instructions.md`
Windsurf	`tl-prompt --minimal >> .windsurfrules`

MCP Server — expose tokenlean as native MCP tools for structured, faster access with no CLI overhead:

# Add to any project's .mcp.json (Claude Code, Codex, etc.)
{
  "mcpServers": {
    "tokenlean": { "command": "tl-mcp" }
  }
}

# Or pick just the tools you need
{ "command": "tl-mcp", "args": ["--tools", "symbols,snippet,run"] }

8 core tools available via MCP: tl_symbols, tl_snippet, tl_run, tl_impact, tl_browse, tl_tail, tl_guard, tl_diff. Structured JSON in/out — no bash command construction, no argument parsing, no stdout scraping.

Hooks — automatically nudge agents toward token-efficient tool usage:

tl-hook install claude-code    # Gentle reminders when agents waste tokens
tl-audit --all --savings       # Measure actual savings across sessions

Agent Skills

Ready-made workflows following the Agent Skills open format, organized for both Claude Code and Codex runtimes.

skills/
  claude/   # Claude Code skill variants
  codex/    # Codex skill variants

Claude Code skills

Skill	What it does
`code-review`	Review PRs efficiently — scope, blast radius, complexity, then targeted code reading
`explore-codebase`	Understand an unfamiliar project in minutes without reading everything
`safe-refactor`	Rename, move, or extract code with impact analysis and verification at each step
`add-feature`	Add functionality by studying existing patterns first — locate, learn conventions, implement, verify
`debug-bug`	Systematic bug investigation — reproduce, localize with blame/history, trace call path, verify fix
`debug-performance`	Measure before optimizing — establish baselines, identify bottlenecks, confirm improvements with numbers
`write-tests`	Write tests by studying existing patterns and code under test before writing assertions
`upgrade-deps`	Upgrade dependencies safely — audit usage, research breaking changes, scale effort to version jump
`migrate-framework`	Incremental framework/API migration with verification at each step, batched by dependency order

Codex skills

Skill	What it does
`code-review`	Risk-first code review workflow for Codex using git diff + targeted validation
`explore-codebase`	Build a fast architecture map in Codex with targeted reads and dependency tracing
`safe-refactor`	Refactor safely in Codex using blast-radius checks and incremental verification
`add-feature`	Add features in Codex by mapping precedent first, then implementing minimal safe changes
`debug-bug`	Repro-first bug fixing workflow in Codex with root-cause tracing and regression checks
`debug-performance`	Performance debugging in Codex with baseline metrics and before/after proof
`write-tests`	Write behavior-focused tests in Codex that match project conventions
`upgrade-deps`	Dependency upgrade workflow in Codex with changelog-driven risk control
`migrate-framework`	Incremental framework/API migrations in Codex with batch-level verification

# Claude Code — copy a skill
cp -r node_modules/tokenlean/skills/claude/code-review ~/.claude/skills/

# Claude Code — copy all skills
cp -r node_modules/tokenlean/skills/claude/* ~/.claude/skills/

# Codex — copy a skill
cp -r node_modules/tokenlean/skills/codex/code-review ~/.codex/skills/

# Codex — copy all skills
cp -r node_modules/tokenlean/skills/codex/* ~/.codex/skills/

# Or clone and pick what you need
git clone https://github.com/edimuj/tokenlean.git
cp -r tokenlean/skills/claude/code-review ~/.claude/skills/
cp -r tokenlean/skills/codex/code-review ~/.codex/skills/

All Tools

Essential — the tools agents use 90% of the time

Tool	Description	Example
`tl-symbols`	Function/class signatures without bodies	`tl-symbols src/utils.ts` or `src/`
`tl-snippet`	Extract one function/class by name	`tl-snippet handleSubmit`
`tl-impact`	Blast radius — what depends on this file	`tl-impact src/auth.ts`
`tl-run`	Token-efficient command output (tests, builds)	`tl-run "npm test"`
`tl-tail`	Token-efficient log tailing and summarization	`tl-tail logs/app.log`
`tl-guard`	Pre-commit check (secrets, TODOs, unused, circular)	`tl-guard`
`tl-structure`	Project overview with token estimates	`tl-structure src/`
`tl-browse`	Fetch any URL as clean markdown	`tl-browse https://docs.example.com`
`tl-context7`	Look up library docs via Context7 API	`tl-context7 react "hooks"`
`tl-component`	React component analyzer (props, hooks, state)	`tl-component Button.tsx`
`tl-analyze`	Composite file profile (5 tools in 1)	`tl-analyze src/auth.ts`

Understanding Code — structure and signatures without reading implementations

Tool	Description	Example
`tl-context`	Estimate token usage for files/dirs	`tl-context src/api/`
`tl-types`	Full TypeScript type definitions	`tl-types src/types/`
`tl-exports`	Public API surface of a module	`tl-exports src/lib/`
`tl-docs`	Extract JSDoc/TSDoc documentation	`tl-docs src/utils/`
`tl-entry`	Find entry points and main files	`tl-entry src/`
`tl-scope`	Show what symbols are in scope at a line	`tl-scope src/cache.mjs:52`
`tl-schema`	Extract DB schema from ORMs/migrations	`tl-schema`
`tl-stack`	Auto-detect project technology stack	`tl-stack`

Before Modifying Files — understand dependencies and impact

Tool	Description	Example
`tl-deps`	Show what a file imports (with tree mode)	`tl-deps src/api.ts --tree`
`tl-related`	Find tests, types, and importers	`tl-related src/Button.tsx`
`tl-flow`	Call graph — what calls this, what it calls	`tl-flow src/utils.ts`
`tl-coverage`	Test coverage info for files	`tl-coverage src/`
`tl-complexity`	Code complexity metrics	`tl-complexity src/ --threshold 10`
`tl-errors`	Map error types and throw points	`tl-errors src/`
`tl-test-map`	Map source files to their test files	`tl-test-map src/cache.mjs`
`tl-style`	Detect coding conventions from code	`tl-style src/`

Understanding History — track changes and authorship

Tool	Description	Example
`tl-diff`	Token-efficient git diff summary	`tl-diff --staged`
`tl-history`	Recent commits for a file	`tl-history src/api.ts`
`tl-blame`	Compact per-line authorship	`tl-blame src/api.ts`
`tl-hotspots`	Frequently changed files (churn)	`tl-hotspots --days 30`
`tl-pr`	Summarize PR/branch for review	`tl-pr feature-branch`
`tl-changelog`	Generate changelog from commits	`tl-changelog --from v1`

Finding Things — search and discover code patterns

Tool	Description	Example
`tl-example`	Find diverse usage examples	`tl-example useAuth`
`tl-search`	Run pre-defined search patterns	`tl-search hooks`
`tl-secrets`	Find hardcoded secrets & API keys	`tl-secrets --staged`
`tl-todo`	Find TODOs/FIXMEs in codebase	`tl-todo src/`
`tl-env`	Find environment variables used	`tl-env --required-only`
`tl-unused`	Find unused exports/files	`tl-unused src/`
`tl-api`	Extract REST/GraphQL endpoints	`tl-api src/routes/`
`tl-routes`	Extract routes from web frameworks	`tl-routes app/`
`tl-npm`	Quick npm package lookup/compare	`tl-npm express fastify`

GitHub Workflows — multi-step gh operations in single commands

Tool	Description	Example
`tl-gh issue view`	View issue + all sub-issues in one call	`tl-gh issue view -R owner/repo 434 --no-body`
`tl-gh issue create-batch`	Create issues in bulk from JSON/JSONL	`echo '[...]' \| tl-gh issue create-batch -R owner/repo`
`tl-gh issue create-tree`	Create parent + children with sub-issue links	`echo '{...}' \| tl-gh issue create-tree -R owner/repo`
`tl-gh issue add-sub`	Link existing issues as sub-issues	`tl-gh issue add-sub -R owner/repo --parent 10 42 43`
`tl-gh issue close-batch`	Close multiple issues with optional comment	`tl-gh issue close-batch -R owner/repo 1 2 3 -c "Done"`
`tl-gh issue label-batch`	Add/remove labels across multiple issues	`tl-gh issue label-batch -R owner/repo --add "P0" 1 2 3`
`tl-gh pr digest`	Full PR status: CI, reviews, comments, merge readiness	`tl-gh pr digest -R owner/repo 123`
`tl-gh pr comments`	Review comments grouped by file with resolution status	`tl-gh pr comments -R owner/repo 123 --unresolved`
`tl-gh pr land`	Check CI, merge, close linked issues, delete branch	`tl-gh pr land -R owner/repo 123`
`tl-gh release notes`	Auto-changelog from commits/PRs, create release	`tl-gh release notes -R owner/repo --tag v1.2.0`

All issue-creating commands support --project owner/N to auto-add to a GitHub project board.

Utilities

Tool	Description	Example
`tl-audit`	Analyze Claude/Codex sessions and estimate token savings	`tl-audit --all --savings`
`tl-quota`	Check AI subscription quota (Claude, Codex)	`tl-quota`
`tl-hook`	Install token-saving agent hooks	`tl-hook install claude-code`
`tl-reddit`	Read Reddit threads as clean text	`tl-reddit <url> -c 20`
`tl-cache`	Manage tokenlean caches	`tl-cache stats`
`tl-config`	Show/manage configuration	`tl-config --init`
`tl-name`	Check name availability (npm/GH/domains)	`tl-name myproject -s`
`tl-playwright`	Headless browser content extraction	`tl-playwright example.com`
`tl-prompt`	Generate AI agent instructions	`tl-prompt --minimal`

Language Support

Code analysis tools are JS/TS-first, but many work across languages. Git-based and search tools work with any language.

	JS/TS	Python	Go	Rust	Ruby	Elixir/Lua	Other
`tl-symbols`	✓	✓	✓	✓	✓	◐	◐
`tl-snippet`	✓	✓	✓	✓	✓	✓	◐
`tl-exports`	✓	✓	✓	◐	◐	◐	◐
`tl-deps`	✓	✓	✓	◐	◐	◐	◐
`tl-impact`	✓	✓	✓	-	-	-	-
`tl-complexity`	✓	✓	✓	-	-	-	-
`tl-flow`	✓	◐	◐	-	-	-	-
`tl-docs`	✓	◐	-	-	-	-	-
`tl-types`	✓	-	-	-	-	-	-
`tl-component`	✓	-	-	-	-	-	-
`tl-style`	✓	-	-	-	-	-	-
`tl-routes`	✓	◐	-	-	-	-	-

✓ full support ◐ partial (regex-based patterns, may miss language-specific constructs) - not supported

Tools not listed (tl-structure, tl-search, tl-diff, tl-todo, tl-secrets, tl-guard, tl-blame, tl-history, tl-hotspots, tl-example, tl-env, tl-run, tl-tail, etc.) are language-agnostic and work with any codebase.

Configuration

Create .tokenleanrc.json in your project root or ~/.tokenleanrc.json globally

{
  "output": {
    "maxLines": 100,
    "maxTokens": null
  },
  "skipDirs": [
    "generated",
    "vendor"
  ],
  "skipExtensions": [
    ".gen.ts"
  ],
  "importantDirs": [
    "domain",
    "core"
  ],
  "importantFiles": [
    "ARCHITECTURE.md"
  ],
  "searchPatterns": {
    "hooks": {
      "description": "Find React hooks",
      "pattern": "use[A-Z]\\w+",
      "glob": "**/*.{ts,tsx}"
    }
  },
  "hotspots": {
    "days": 90
  },
  "structure": {
    "depth": 3
  },
  "cache": {
    "enabled": true,
    "ttl": 300,
    "maxSize": "100MB",
    "location": null
  }
}

Config values extend built-in defaults (they don't replace them).

Caching

tokenlean caches expensive operations with git-based invalidation — including ripgrep-backed searches, cached JS/TS semantic facts for tl-symbols and tl-snippet, and the JS/TS dependency graph used by tl-deps and tl-impact. Cache entries invalidate automatically on commits or file changes.

tl-cache stats      # View cache statistics
tl-cache clear      # Clear cache for current project
tl-cache clear-all  # Clear all cached data

Disable with TOKENLEAN_CACHE=0 or in config: {"cache":{"enabled":false}}

Workflows

Starting on an unfamiliar codebase

tl-structure                    # Get the lay of the land
tl-entry                        # Find entry points
tl-exports src/lib/             # Understand the public API
tl-docs src/utils/              # Read documentation, not code
tl-types src/types/             # Understand data shapes
tl-schema                       # Understand the database

Before refactoring a file

tl-impact src/core/auth.ts      # What would break?
tl-deps src/core/auth.ts        # What does it depend on?
tl-related src/core/auth.ts     # Find the tests
tl-coverage src/core/auth.ts    # Is it well tested?
tl-complexity src/core/auth.ts  # How complex is it?

Understanding a component

tl-component src/Button.tsx     # Props, hooks, dependencies
tl-symbols src/Button.tsx       # Function signatures (or src/ for all)
tl-symbols src/ --filter function # Functions only across directory
tl-history src/Button.tsx       # Recent changes
tl-blame src/Button.tsx         # Who wrote what

Finding technical debt

tl-complexity src/ --threshold 15  # Complex functions
tl-unused src/                     # Dead code
tl-todo                            # Outstanding TODOs
tl-hotspots                        # Frequently changed (unstable?)

Security check before committing

tl-secrets                         # Scan for hardcoded secrets
tl-secrets --staged                # Only check staged files
tl-secrets --min-severity high     # Only high severity issues

Reviewing a PR

tl-pr feature-branch               # Summary of branch changes
tl-pr 123                          # GitHub PR #123 (needs gh CLI)
tl-pr --full                       # Include files, stats, commits
tl-gh pr digest -R owner/repo 123  # Full status: CI, reviews, comments, readiness
tl-gh pr comments -R owner/repo 123 --unresolved  # Unresolved review threads

Preparing a release

tl-changelog --unreleased          # What's new since last tag
tl-changelog v0.1.0..v0.2.0       # Between versions
tl-changelog --format compact      # Quick summary
tl-gh release notes -R owner/repo --tag v1.2.0 --dry-run  # Preview auto-changelog
tl-gh release notes -R owner/repo --tag v1.2.0             # Create GitHub release

Starting a new project

tl-name coolproject awesomelib     # Check npm, GitHub, domains
tl-name myapp -s                   # Suggest variations if taken
tl-npm express fastify koa         # Compare framework options

Running commands efficiently

tl-run "npm test"                  # Summarize test results
tl-run "npm run build"             # Extract build errors only
tl-run "eslint src/"               # Summarize lint violations
tl-run "npm test" --raw            # Full output with stdout/stderr preserved
tl-run "npm test" --raw -j         # Raw JSON includes separate stdout/stderr fields
tl-run "npm test" -j               # Structured JSON output
tl-tail logs/app.log               # Collapse repeats + surface errors/warnings
tl-tail logs/app.log -f            # Follow file updates with compact summaries
npm test 2>&1 | tl-tail            # Summarize piped logs

Looking up documentation

tl-browse https://docs.example.com/api  # Fetch docs as markdown
tl-context7 react "useEffect"           # Look up React docs via Context7
tl-context7 nextjs "app router"         # Next.js docs
tl-npm lodash --deps                    # Check package dependencies
tl-npm chalk --versions                 # Version history

Measuring token savings

# run without install
npx --package tokenlean tl-audit --latest                  # Direct tool invocation via npx
npx tokenlean audit --all --savings                        # Package entrypoint via npx

# provider-aware sessions
tl-audit --provider claude --latest                       # Claude Code only
tl-audit --codex --latest                                 # Codex only
tl-audit --latest --savings                               # Auto-detect provider; combined summary

# output detail levels
tl-audit --all --savings                                  # Summary only, across all matching sessions
tl-audit -n 5 --verbose --savings                         # Add per-session detail
tl-audit session.jsonl                                    # Analyze a specific session file

tl-audit analyzes both Codex and Claude Code sessions:

Opportunities — tokens wasted on large file reads, verbose build output, raw grep/cat/tail
Savings (with --savings) — tokens already saved by tokenlean usage, with capture rate
Add --verbose for per-session breakdown

Summary (270 sessions: 180 Claude Code, 90 Codex)
  Still saveable:     496k of 661k (75%)
  By provider:
  Claude Code       180 sessions     341k saveable     1.5M saved
  Codex              90 sessions     155k saveable     820k saved
  Already saved:      2.3M (531 tokenlean uses)
  Capture rate:       82% of potential savings realized

Install hooks to automatically nudge agents toward token-efficient alternatives:

# Claude Code — PreToolUse hooks (nudge toward better tools)
tl-hook install claude-code        # Install hooks (auto-detects claude-rig)
tl-hook install claude-code --global   # Force install to ~/.claude/
tl-hook install claude-code --rig dev  # Install to a specific rig
tl-hook status claude-code         # Check what's active
tl-hook uninstall claude-code      # Remove hooks

# Open Code — plugin (auto-wraps commands with tl-run/tl-browse)
tl-hook install opencode           # Install plugin to ~/.config/opencode/plugins/
tl-hook status opencode            # Check if installed
tl-hook uninstall opencode         # Remove plugin

GitHub batch operations

# View an issue with all its sub-issues (one API call)
tl-gh issue view -R owner/repo 434              # Bodies truncated to 5 lines
tl-gh issue view -R owner/repo 434 --no-body    # Compact: titles + labels only
tl-gh issue view -R owner/repo 434 --full       # Complete bodies

# Create issues in bulk from JSON
echo '[{"title":"Bug A","labels":["bug"]},{"title":"Bug B"}]' | \
  tl-gh issue create-batch -R owner/repo --project edimuj/1

# Create an epic with sub-issues
echo '{"title":"Epic","children":[{"title":"Task 1"},{"title":"Task 2"}]}' | \
  tl-gh issue create-tree -R owner/repo --project edimuj/1

# Sprint cleanup — close a batch with comment
tl-gh issue close-batch -R owner/repo 10 11 12 -c "Sprint complete"

# Label triage
tl-gh issue label-batch -R owner/repo --add "P1" --remove "triage" 5 6 7

# Land a PR (wait for CI, merge, close linked issues, delete branch)
tl-gh pr land -R owner/repo 123 --method squash

Extracting web content

tl-browse https://example.com/docs        # Fast: native markdown or HTML conversion
tl-browse https://example.com -t 2000     # Limit to ~2000 tokens
tl-playwright example.com                 # Full: headless browser (JS-rendered pages)
tl-playwright example.com -s "h1,h2,h3"  # Extract headings only
tl-playwright example.com --screenshot p  # Save screenshot

Design Principles

Single purpose — one tool, one job
Minimal output — show what's needed, nothing more
Composable — every tool supports -j for JSON piping
Fast — no heavy parsing, no external services, aggressive caching
Multi-language — JS/TS first, expanding to Python, Go, Rust, Ruby

Also by Exelerus

Project	Description
claude-rig	Run multiple Claude Code profiles side-by-side — isolate or share settings, plugins, MCPs per rig
agent-awareness	Modular awareness plugins for AI coding agents
claude-mneme	Persistent memory for Claude Code — context across sessions
claude-simple-status	Minimal statusline — model, context usage, quota at a glance
vexscan-claude-code	Security scanner for untrusted plugins, skills, MCPs, and hooks

Changelog

Use tl-changelog to generate changelogs from git history on demand:

tl-changelog                      # Since last tag
tl-changelog v0.19.0..v0.21.0    # Between versions
tl-changelog --unreleased         # What's new since last release

Contributing

Contributions are welcome! See CONTRIBUTING.md for guidelines on adding tools, code style, and submitting PRs.

Name		Name	Last commit message	Last commit date
Latest commit History 161 Commits
.github		.github
assets		assets
benchmarks		benchmarks
bin		bin
scripts		scripts
skills		skills
src		src
.gitignore		.gitignore
CONTRIBUTING.md		CONTRIBUTING.md
LICENSE		LICENSE
README.md		README.md
package-lock.json		package-lock.json
package.json		package.json

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tokenlean

The Problem

How much are you wasting?

Install

Quick Reference

AI Agent Integration

Agent Skills

Claude Code skills

Codex skills

All Tools

Language Support

Configuration

Workflows

Design Principles

Also by Exelerus

Changelog

Contributing

License

About

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Contributors

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tokenlean

The Problem

How much are you wasting?

Install

Quick Reference

AI Agent Integration

Agent Skills

Claude Code skills

Codex skills

All Tools

Language Support

Configuration

Workflows

Design Principles

Also by Exelerus

Changelog

Contributing

License

About

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Resources

License

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