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### **Control what your AI can see.** **LeanCTX — Lean Context Engineering for AI agents** LeanCTX — short for **Lean Context** — is the context engineering layer for AI agents. It runs as a single local binary between your agents and everything they touch — your code, shell, data, and the model itself: it **decides** what they read, **compresses** what they send (an optional local proxy shrinks every request — system prompt, history and tool results — prompt-cache-safe), **remembers** what they learn, **guards** what they touch — and **proves** what they save with a signed, verifiable savings ledger. The result: 60–90% fewer tokens. Zero config required. Local-first. | Problem | With LeanCTX | |---------|-------------| | Repeated file reads: ~2000 tokens each | Cached re-reads: **~13 tokens** | | Raw `git status`: ~800 tokens | Compressed: **~120 tokens** | | Every turn re-sends the whole history | Proxy compresses each request, **prompt-cache-safe** | | Context resets every chat | Session memory persists across chats | | No visibility into context usage | Real-time dashboard + budget control | ---

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--- > **Control what your AI can see.** LeanCTX — short for **Lean Context** — is the **context engineering layer** for AI agents: one local Rust binary that decides what your agents read, compresses what they send to the model, remembers what they learn, guards what they touch — and proves what they save. > Token savings are the receipt. Intelligence is the product. Works with **Cursor, Claude Code, Copilot, Windsurf, Codex, Gemini** and 30+ other agents — no config needed.

See it in action:

Map-mode file read + compressed git output demo
Read + Shell
Map-mode reads + compressed CLI output 		lean-ctx gain live dashboard demo
Gain (live)
Tokens + USD savings in real time 		lean-ctx benchmark report demo
Benchmark proof
Measure compression by language + mode

All GIFs are generated from reproducible VHS tapes in demo/.

## Why developers use LeanCTX - **Longer useful coding sessions** — less context waste = more room for actual code reasoning - **Lower API costs** — 60–90% fewer tokens on reads and shell output, cached re-reads cost ~13 tokens - **No more "I already showed you this file"** — session memory persists across chats - **Works with your existing setup** — one `lean-ctx setup` command, no config changes needed - **Full visibility** — see exactly where your context window budget goes - **Model-agnostic & yours** — swap OpenAI/Anthropic/Gemini freely; your context and memory stay local and portable, never locked in a vendor's black box ---

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--- ## Why now — own your context Models are converging on commodity. The durable edge isn't *which* model you call — it's your **context**: what your agents read, what they remember, and what you can prove. And the layer that optimizes and *owns* that context can't come from the vendor that bills per token or keeps your memory in a black box — it has to sit on your side. That's the shift behind "agent entities" that live in your chat and remember your company (Claude in Slack, ClickUp Brain): a **context login, not a model login** — you end up renting your own company knowledge back. LeanCTX is the opposite layer. It keeps the moat yours: local-first, portable (`.ctxpkg`), and model-agnostic — swap OpenAI, Anthropic or Gemini without losing context or cache. **Own your context; don't rent it back.** --- ## What it does — the four dimensions of context LeanCTX treats context as a managed resource, not an afterthought. One binary covers the four dimensions that decide how well an AI agent actually performs: ### 1. Compression — input efficiency Your AI agent reads files and runs commands. LeanCTX compresses both automatically. - **File reads**: 10 read modes (`full`, `map`, `signatures`, `diff`, `lines:N-M`, `density:X`, …) — cached re-reads cost ~13 tokens - **Target density** (`density:0.4`): SDE-style budget compression — keeps the highest-entropy lines until ~40% of the original tokens remain, deterministic - **JIT disclosure**: `signatures` carries line spans and points at `lines:N-M` for targeted expansion — outline first, bodies on demand - **Shell output**: 95+ shell-output patterns compress git, npm, cargo, docker, kubectl, terraform and more (270 passthrough rules) - **Tree-sitter AST**: structural understanding for 27 languages — not just text compression - **Reversible by design (CCR)**: compression never *discards* content — pruned or truncated payloads move to a content-addressed store with a deterministic handle, so the model can pull the original bytes back on demand via `ctx_expand`, `ctx_retrieve`, an in-band marker, or `GET /v1/references/{id}`. [Five recovery paths →](docs/comparisons/vs-headroom.md#reversibility) ### 2. Routing — the right fidelity per read Not every file needs the same depth. LeanCTX sends the signal, not the noise. - **10 read modes**: from full content down to AST signatures and entropy-filtered views - **Adaptive `ModePredictor`**: learns the optimal read mode per file type from past sessions - **`IntentEngine`**: classifies query complexity so simple lookups stay cheap ### 3. Memory — context that persists Context doesn't disappear between chats anymore. - **Session memory (CCP)**: persist task/facts/decisions across chats — structured recovery queries survive compaction - **Knowledge graph**: temporal facts with validity windows, episodic + procedural memory - **Property Graph**: multi-edge code graph (imports, calls, exports, type_ref) powers impact analysis and search ranking - **Yours, not the vendor's**: memory stays local and portable — export it as a `.ctxpkg` package and move it across machines or models, instead of locking it in a vendor's black box ### 4. Verification — control what reaches the model Performance is accuracy, not just speed. You stay in control of the window. - **Context Manager**: browser dashboard with real-time token tracking, compression stats, utilization gauge - **Budgets & SLOs**: profiles, roles, per-agent budgets, and throttling policies - **Context Proof** (`ctx_proof`, `ctx_verify`): 4-layer verification engine with CI drift gates
Full feature list (81 MCP tools) - **Web & Research** (`ctx_url_read`): pull a public web page, PDF, or YouTube transcript into context as compressed, citation-backed text — `facts`/`quotes` return claims with a confidence score + source URL, relevance-ranked research-compression distils to a token budget, SSRF-guarded (http/https only) - **Graph-Powered Intelligence**: hybrid search (BM25 + embeddings + graph proximity via RRF), incremental git-diff updates - **LSP Refactoring** (`ctx_refactor`): language-server-powered rename, references, go-to-definition via rust-analyzer, typescript-language-server, pylsp, gopls - **Multi-Agent** (`ctx_agent`, `ctx_handoff`): agent handoff with context transfer bundles, diary system, synchronized shared state - **Archive Full-Text Search** (`ctx_expand search_all`): FTS5-powered cross-archive search over all previously archived tool outputs - **PR Context Packs**: `lean-ctx pack --pr` builds a PR-ready context pack (changed files, related tests, impact, artifacts) - **Context Packages**: `lean-ctx pack create` bundles Knowledge + Graph + Session into portable `.ctxpkg` files with SHA-256 integrity - **Context Time Machine**: `lean-ctx snapshot create|list|show|verify|restore|publish|import` — git-anchored, ed25519-signed snapshots of the layer state (lineage, ledger Φ, ROI, session) on an append-only timeline; replay them in the dashboard, `restore` to resume a session (and `--git` to check out the commit), or `publish`/`import` a signed snapshot to share it ([concept →](docs/concepts/context-time-machine.md)) - **Observability**: `lean-ctx gain --live` for real-time savings, `lean-ctx wrapped` for weekly/monthly summaries (`gain --svg`/`--share` for a shareable card or self-hostable page), `lean-ctx watch` for TUI monitoring - **Verified savings**: `lean-ctx savings` is an auditable, per-event ledger (tokenizer transparency, bounce-netting, tamper-evident SHA-256 chain) — local-only, on by default - **HTTP mode**: `lean-ctx serve` for Streamable HTTP MCP + `/v1/tools/call` (used by the Cookbook + SDK)
## Addons — run the ecosystem through one gateway You don't have to choose between LeanCTX and the other context tools you already like. An **addon** wraps any MCP server in a tiny `lean-ctx-addon.toml` manifest; LeanCTX runs it behind its gateway with one command, then treats what it returns like your own reads instead of just proxying it. ```bash lean-ctx addon search memory # browse the registry by category lean-ctx addon add headroom # installs the upstream package + wires the MCP server, on add lean-ctx addon list # what's wired into your gateway ``` - **One command to add** — `addon add ` installs the upstream package via its native manager (uv, pip, cargo, npm, brew, dotnet) and wires the MCP server into your gateway. No fork, no recompile. - **Folded in, not just proxied** — opt-in post-processing runs addon output through the same pipeline as your code: compress to a budget, spill oversized blobs to a `ctx_expand` handle, index into BM25 / graph / knowledge. Typed adapters route specific tools straight into `ctx_expand`, `ctx_callgraph` and `ctx_knowledge`. - **Untrusted by default** — every addon's output is scrubbed for secrets and tagged untrusted before it reaches the model. Always on, not a flag. - **You stay in control** — pin a machine or fleet to verified-only, an allowlist, or off entirely via one `[addons]` policy a single repo can't override. The registry spans compression (Headroom, Sophon), code intelligence (Repomix, Serena), memory (Mem0, Cognee, Letta) and reasoning (Sequential Thinking). See the **[addon guide](docs/guides/addons.md)** or [browse them all](https://leanctx.com/addons/). ## Where it's going LeanCTX is growing from a single context *layer* into a full **cognitive context layer** for whole teams: version-controlled context strategy, one unified graph, and a governance layer across many agents. - **Context Time Machine → hosted history** — the snapshot engine, dashboard replay, restore, and signed file-based share/import have shipped (see above); next is a `ctxpkg.com` registry for hosted, versioned context history and a side-by-side model-view ｜ git-diff replay. The temporal axis through everything LeanCTX does — it *decides, remembers, guards, proves, and replays*. ([concept →](docs/concepts/context-time-machine.md)) - **Context as Code** — declarative pipelines, profiles, and policies in TOML, versioned like infrastructure - **Unified Context Graph** — code, tests, commits, CI runs, and knowledge entries in a single semantic graph - **Agent Harness** — roles, budgets, and tool permissions for multi-agent governance - **Context Observability** — SLOs on context consumption, anomaly detection, OpenTelemetry / Prometheus export The full roadmap lives in **[VISION.md](VISION.md)**. ## How it works (30 seconds) LeanCTX works on **two planes** — what your agents *read* and what they *send to the model*: ``` read path: AI tool → (MCP tools + shell) → lean-ctx → your repo + CLI wire path: AI tool → lean-ctx proxy → model provider (every request, compressed) ``` - **MCP server** *(read path)*: exposes `ctx_*` tools (read modes, caching, deltas, search, memory, multi-agent) - **Shell hook** *(read path)*: transparently compresses common commands so the LLM sees less noise - **Request proxy** *(wire path, opt-in)*: `lean-ctx proxy enable` puts a local proxy between your agent and the model that compresses **every request** — system prompt, full history and tool results — prompt-cache-safe, with measured USD spend. It can also pin **one reasoning-effort level across OpenAI, Anthropic & Gemini** (`proxy.effort`) without breaking that cache, cut **output** tokens with a cache-safe verbosity steer plus a measured holdout, and **relocate volatile fields** (dates, UUIDs, commit SHAs) out of the cacheable prefix so a stable system prompt finally caches. Every rewrite is reversible (content-addressed recovery) and byte-stable by contract. Same layer as a standalone request-compression proxy (e.g. Headroom) — you don't need one on top. - **Property Graph**: multi-edge code graph powers impact analysis, related file discovery, and search ranking - **Session memory**: persists state with structured recovery so long-running work never "cold starts" - **Context Manager**: browser dashboard for real-time visibility into what's in your context window ## Get started (30 seconds) ```bash # 1) Install (pick one) curl -fsSL https://leanctx.com/install.sh | sh # universal (no Rust needed) brew tap yvgude/lean-ctx && brew install lean-ctx # macOS / Linux npm install -g lean-ctx-bin # Node.js cargo install lean-ctx # Rust pi install npm:pi-lean-ctx # Pi Coding Agent # 2) One-command setup for your agent lean-ctx wrap cursor # or: wrap claude / wrap codex / wrap vscode # Done. Savings appear after your AI's first lean-ctx call. lean-ctx gain ``` `lean-ctx wrap` installs shell hooks, registers the MCP server, sets up agent hooks, starts the daemon, and verifies the connection — all in one command. Undo anytime with `lean-ctx unwrap cursor`.
Alternative: full control ```bash lean-ctx onboard # connect all detected AI tools (zero prompts) lean-ctx setup # interactive wizard with every option ```
**Building from source on Windows?** Clone the repo and run `./install.ps1` in PowerShell — it builds the release binary and installs it into Cargo's bin directory (pass `-BuildOnly` to build without installing).
Troubleshooting / Safety - Disable immediately (current shell): `lean-ctx-off` - Run a single command uncompressed: `lean-ctx -c --raw "git status"` - Only activate in AI agent sessions: set `shell_activation = "agents-only"` in `~/.config/lean-ctx/config.toml` - Per-project config override: create `.lean-ctx.toml` in your project root (auto-merged with global config) - Docker projects sharing `/workspace`: create `.lean-ctx-id` with a unique name to prevent context collisions - Update: `lean-ctx update` - Diagnose (shareable): `lean-ctx doctor --json`
## Use it from your own code (SDKs) Beyond the CLI, lean-ctx ships published libraries so you can call it directly from your app. **Drop-in prompt compression — [`lean-ctx-sdk`](https://pypi.org/project/lean-ctx-sdk/) ([npm](https://www.npmjs.com/package/lean-ctx-sdk)).** Compress a chat-style `messages` array before it reaches any model — deterministic and prompt-cache friendly; images, tool-calls and ids pass through untouched. ```python # pip install lean-ctx-sdk from lean_ctx import compress messages = compress(messages, model="claude-sonnet-4") ``` ```ts // npm install lean-ctx-sdk import { compress } from "lean-ctx-sdk"; messages = await compress(messages, { model: "gpt-4o" }); ``` Framework adapters included (LiteLLM, LangChain, Vercel AI SDK). → **[compress() cookbook](docs/guides/compress-sdk.md)** **Thin `/v1` contract clients — [`lean-ctx-client`](https://pypi.org/project/lean-ctx-client/) ([npm](https://www.npmjs.com/package/lean-ctx-client) · [crates.io](https://crates.io/crates/lean-ctx-client)).** Wrap the full `/v1` tool, event and session API over the process boundary — never links the engine, so it stays stable as lean-ctx evolves. ```bash pip install lean-ctx-client # Python (imports as `leanctx`) npm install lean-ctx-client # TypeScript / Node cargo add lean-ctx-client # Rust ``` Start the server with `lean-ctx serve`, then point a client at it. → **[API reference](https://leanctx.com/docs/api-reference/)** ## Real-world scenarios LeanCTX grows with you. Below are the journeys most people actually take — each links to a complete, function-by-function walkthrough in the **[Reference](docs/reference/README.md)** (every CLI command and all 79 MCP tools are documented there).
### 🟢 Your first 30 seconds *"I just installed it — now what?"* ```bash lean-ctx wrap cursor # one-command setup for your agent lean-ctx doctor # confirm you're wired up ``` One command installs hooks, MCP registration, and verifies the connection. → **[Journey 1 — Setup & Onboarding](docs/reference/01-setup-and-onboarding.md)** ### 📖 Coding every day *"Stop re-reading the same files."* ```bash lean-ctx read src/server.rs -m map # API surface, ~13 tok on re-read lean-ctx -c "git status" # compressed shell output ``` Your agent reads less and searches smarter — automatically. → **[Journey 2 — Daily Use](docs/reference/02-daily-use.md)**
### 🧠 Resume where you left off *"My new chat forgot everything."* ```bash lean-ctx overview # task-aware project recap lean-ctx knowledge recall "auth" # facts that survive resets lean-ctx knowledge consolidate # import session + compact lifecycle lean-ctx knowledge consolidate --all # compact every project store ``` Session memory + a project knowledge graph persist across chats. → **[Journey 3 — Memory & Knowledge](docs/reference/03-memory-and-knowledge.md)** ### 🗺️ Understand a new codebase *"Where does this function ripple to?"* ```bash lean-ctx graph impact src/auth.rs # blast radius lean-ctx smells scan # code-smell hotspots ``` A multi-edge property graph powers impact analysis + ranked search. → **[Journey 4 — Code Intelligence](docs/reference/04-code-intelligence.md)**
### 🔌 Providers & multi-repo *"Pull in GitHub issues and our Postgres schema."* ```bash lean-ctx provider list lean-ctx serve --root ./api --root ./web # multi-repo ``` External data flows through the same consolidation pipeline. → **[Journey 5 — Advanced & Integrations](docs/reference/05-advanced.md)** ### 🛠️ Keep it healthy *"Update, fix, or cleanly remove."* ```bash lean-ctx doctor --fix lean-ctx update ``` Self-healing diagnostics; surgical uninstall that only removes its own blocks. → **[Journey 6 — Lifecycle & Troubleshooting](docs/reference/06-lifecycle.md)**
### 🎛️ Take control of the window *"Budget my context like a pro."* ```bash lean-ctx plan "refactor billing" --budget 8000 lean-ctx compile --mode balanced ``` Phi-scored planning + knapsack compilation + a context ledger. → **[Journey 7 — Context Engineering](docs/reference/07-context-engineering.md)** ### 🤝 Run a team of agents *"Planner + coder + reviewer on one repo."* ```text ctx_agent action=register role=dev ctx_handoff action=create # baton-pass with full context ``` Shared message bus, diaries, knowledge, and deterministic handoffs. → **[Journey 8 — Multi-Agent Collaboration](docs/reference/08-multi-agent.md)**
### 🏢 Share across a team / CI *"One shared index, headless in pipelines."* ```bash lean-ctx team serve --config team.toml lean-ctx bootstrap # zero-prompt CI setup ``` Scoped tokens, optional cloud sync, verifiable context gates. → **[Journey 9 — Team, Cloud & CI](docs/reference/09-team-cloud-ci.md)** ### 🎚️ Tune & govern *"Make it behave exactly how we want."* ```bash lean-ctx compression standard lean-ctx harden # enforce token discipline ``` Compression levels, tool profiles, themes, and rules governance. → **[Journey 10 — Customization & Governance](docs/reference/10-customization-and-governance.md)**
### 📊 Prove the payoff *"Show me the numbers."* ```bash lean-ctx gain --deep # savings, cost, per-agent, heatmap lean-ctx wrapped # shareable recap (also: gain --svg / gain --share) lean-ctx savings # verified per-event ledger (auditable; savings verify) ``` All analytics live in the CLI/dashboard — never burning agent tokens. → **[Journey 11 — Analytics & Insights](docs/reference/11-analytics-and-insights.md)** ### 📚 The full reference *"I want to read everything."* Every command and all 81 MCP tools, organized as user journeys, plus appendices for the [CLI map](docs/reference/appendix-cli-map.md), [MCP tools](docs/reference/appendix-mcp-tools.md), and [paths & config](docs/reference/appendix-paths-and-config.md). → **[Reference index](docs/reference/README.md)**
## Supported IDEs & AI tools LeanCTX is a standard **MCP server**, so it works with any MCP-compatible client. Two integration modes are auto-selected per agent: | Mode | How it works | Best for | |---|---|---| | **Hybrid** | MCP for cached reads (~13 tokens) + shell hooks for command compression | Agents with shell access (Cursor, Claude Code, Codex, ...) | | **MCP** | All 80 tools via MCP protocol, no shell hooks | Protocol-only agents (JetBrains, VS Code, Zed, ...) | ### Agent compatibility matrix | Agent | Hybrid | MCP | Setup | |---|:---:|:---:|---| | Cursor | ● | | `lean-ctx init --agent cursor` | | Claude Code | ● | | `lean-ctx init --agent claude` | | CodeBuddy | ● | | `lean-ctx init --agent codebuddy` | | Augment CLI / VS Code | ● | | `lean-ctx init --agent augment` | | Codex CLI | ● | | `lean-ctx init --agent codex` | | Gemini CLI | ● | | `lean-ctx init --agent gemini` | | Windsurf | ● | | `lean-ctx init --agent windsurf` | | GitHub Copilot | ● | | `lean-ctx init --agent copilot` | | CRUSH | ● | | `lean-ctx init --agent crush` | | Hermes | ● | | `lean-ctx init --agent hermes` | | OpenCode | ● | | `lean-ctx init --agent opencode` | | Pi | ● | | `lean-ctx init --agent pi` | | Qoder | ● | | `lean-ctx init --agent qoder` | | Amp | ● | | `lean-ctx init --agent amp` | | Cline | ● | | `lean-ctx init --agent cline` | | Roo Code | ● | | `lean-ctx init --agent roo` | | Kiro | ● | | `lean-ctx init --agent kiro` | | Antigravity | ● | | `lean-ctx init --agent antigravity` | | Amazon Q | ● | | `lean-ctx init --agent amazonq` | | Qwen | ● | | `lean-ctx init --agent qwen` | | Trae | ● | | `lean-ctx init --agent trae` | | Verdent | ● | | `lean-ctx init --agent verdent` | | Aider | | ● | `lean-ctx init --agent aider` | | Continue | | ● | `lean-ctx init --agent continue` | | JetBrains IDEs | | ● | `lean-ctx init --agent jetbrains` | | QoderWork | | ● | `lean-ctx init --agent qoderwork` | | VS Code | | ● | `lean-ctx init --agent vscode` | | Zed | | ● | `lean-ctx init --agent zed` | | Neovim | | ● | `lean-ctx init --agent neovim` | | Emacs | | ● | `lean-ctx init --agent emacs` | | Sublime Text | | ● | `lean-ctx init --agent sublime` | > **Any MCP-compatible client** works out of the box — the table above shows agents with first-class auto-setup. ### When to use (and when not to) **Great fit if you...** - use AI coding tools daily and your sessions are shell-heavy (git/tests/builds) - work in medium/large repos (50+ files / monorepos) - want a local-first layer with **no telemetry by default** **Skip it if you...** - mostly work in tiny repos and rarely call the shell from your AI tool - always need raw/unfiltered logs (you can still use `--raw`, but ROI is lower) The honest fine print: the payoff depends on three levers — **reach** (own the window via the proxy/engine, not just the `ctx_*` tool layer), **context lifetime** (one long-lived session vs. a fresh process per phase), and **provider pricing** (prompt-cache-priced vs. re-billed every turn). They stack into a clear win where they line up and net to **break-even** where they don't. See the [win vs. break-even matrix](docs/reference/14-performance-tuning.md#win-vs-break-even-at-a-glance) for the full breakdown and how to tune for each case. ## Demo Try these in any repo: ```bash lean-ctx read rust/src/server/mod.rs -m map lean-ctx -c "git log -n 5 --oneline" lean-ctx gain --live lean-ctx dashboard # Context Manager (browser) lean-ctx watch # TUI monitor lean-ctx benchmark report . ``` - The repo ships the exact tapes used to render the GIFs in `demo/` - Regenerate locally: ```bash vhs demo/leanctx.tape vhs demo/gain.tape vhs demo/benchmark.tape ``` ## Benchmarks Real, reproduced numbers — never estimated. Measured on this repo with the GPT-4o tokenizer (`o200k_base`); a tool that isn't installed is reported as such, never guessed. | Read mode | Compression | Tokens (50 files) | Quality | |---|---:|---:|---:| | Raw read | 0% | 533.2K | 100% | | `map` | **98.1%** | 8.0K | 78% | | `signatures` | **96.7%** | 14.0K | 96% | | Cached re-read | ~99.99% | ~13 tok | 100% | lean-ctx's **own cost is measured too**: the fixed per-session footprint it injects (advertised tool schemas + MCP instructions) is ~2.1K tokens and CI-gated via `lean-ctx doctor overhead --gate`, so it can only shrink. And the long-lived proxy rail has a deterministic self-verify — `lean-ctx benchmark dual-arm --json` replays a 15-turn session and prices it per model (digest `f5ed145e61ce3689`, 99.4% input-side saving on cache-priced rails; methodology: [bench/agent-task/r2](bench/agent-task/r2/README.md)). Accuracy isn't a vibe: the lossy stages are **CI-gated**. A model-free A/B gate proves the JSON crusher keeps *every* gold answer while cutting tokens, and proxy rewrites are byte-stable by contract, so Anthropic (90%) / OpenAI (50%) prompt-cache discounts survive compression. A deterministic **off-vs-on testbench** (`lean-ctx eval testbench`) extends the proof to *answers*: it runs pinned real repos through a raw-dump baseline and through lean-ctx at an identical token budget, grades free-form QA with an LLM judge and code with each repo's own tests, and emits `FINDINGS.md` (tokens / turns / walltime / quality) plus a regressions file — with a committed recorded subset that blocks CI on any regression. - **Latest snapshot**: [BENCHMARKS.md](BENCHMARKS.md) - **Reproduce**: `lean-ctx benchmark report .` ## By the numbers - **3,000+ GitHub stars** — and counting - **280+ forks** — active community contributions - **200+ releases** — shipped near-daily since launch - **30+ supported AI coding agents** — broadest MCP compatibility - **81 MCP tools** — from simple file reads to multi-agent orchestration - Used in production by teams running Claude Code, Cursor, and Codex daily - **Live adoption metrics**: [leanctx.com/metrics](https://leanctx.com/metrics/) — installs, stars and savings, updated continuously ## Docs - **Reference (every function, by user journey)**: [docs/reference/](docs/reference/README.md) — 11 journeys + CLI/MCP/config appendices - **For AI agents / LLMs**: [llms.txt](llms.txt) — a curated, machine-readable map of lean-ctx (per the [llms.txt](https://llmstxt.org) convention) - Getting started: https://leanctx.com/docs/getting-started - Tools reference: https://leanctx.com/docs/tools/ - CLI reference: https://leanctx.com/docs/cli-reference/ - What is LeanCTX: https://leanctx.com/what-is-leanctx/ - Comparison (vs RTK, Context+, MemGPT): https://leanctx.com/compare/ - Pricing & Cloud (local use is free forever): https://leanctx.com/pricing/ - FAQ: [discord-faq.md](discord-faq.md) - Feature catalog (SSOT snapshot): [LEANCTX_FEATURE_CATALOG.md](LEANCTX_FEATURE_CATALOG.md) - Monorepo guide: [docs/guides/monorepo.md](docs/guides/monorepo.md) - Architecture: [ARCHITECTURE.md](ARCHITECTURE.md) - Vision: [VISION.md](VISION.md) ## Privacy & security - **No telemetry by default** - **Optional anonymous stats sharing** (opt-in during setup) - **Disableable update check** (config `update_check_disabled = true` or `LEAN_CTX_NO_UPDATE_CHECK=1`) - **40+ security hardening fixes** in v3.5.16 (path traversal, injection, CSPRNG, CSP, resource limits — [details](CHANGELOG.md)) - **Context Governance Benchmark self-assessment**: graded **C2 — Managed** against the 32-control [CGB v1.0-draft](https://github.com/yvgude/context-governance-benchmark) spec, gaps declared — [docs/compliance/cgb-self-assessment.md](docs/compliance/cgb-self-assessment.md) - Runs locally; your code never leaves your machine unless you explicitly enable cloud sync See [SECURITY.md](SECURITY.md). ## Uninstall One command removes **everything** — it stops all processes, then deletes hooks, editor configs, rules, autostart (LaunchAgent/systemd), the data dir, **and the binary itself**: ```bash lean-ctx uninstall # full clean removal lean-ctx uninstall --dry-run # preview every change, write nothing lean-ctx uninstall --keep-config # keep MCP configs + rules (for reinstall) lean-ctx-off # or just disable for the current shell session ``` No binary on PATH (or you used the curl installer)? Run the same removal from the installer: ```bash curl -fsSL https://leanctx.com/install.sh | sh -s -- --uninstall ``` If you installed via a package manager, `uninstall` removes everything it wrote and tells you the one command to finish removing the binary: ```bash brew uninstall lean-ctx # Homebrew cargo uninstall lean-ctx # cargo install npm uninstall -g lean-ctx-bin # npm pi uninstall npm:pi-lean-ctx # Pi Coding Agent ``` ## Star History Star History Chart ## Contributing Start with [CONTRIBUTING.md](CONTRIBUTING.md). Easy first PR: propose a new CLI compression pattern via the [issue template](.github/ISSUE_TEMPLATE/compression_pattern.md). ## License Apache License 2.0 — see [LICENSE](LICENSE). --- lean-ctx: ctx_compose bundles search+read+symbols in one call ---