lean-ctx MCP — Casos de uso, Instalar & Demo ao vivo

Por que usar

Principais recursos

42 MCP tools: 8 file read modes, smart search, session memory, multi-agent sharing
Shell hook compresses 90+ CLI command patterns (git, docker, npm, cargo, etc.)
8 file read modes: full, map, signatures, diff, aggressive, entropy, task, lines
Single Rust binary — fast startup, <1ms overhead, zero telemetry
One-command setup for 24 AI coding tools
Tree-sitter AST parsing for 18 languages

Demo ao vivo

Como fica na prática

lean-ctx.replay ▶ pronto

0/0

Instalar

Escolha seu cliente

~/Library/Application Support/Claude/claude_desktop_config.json · Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "lean-ctx": {
      "command": "TODO",
      "args": [
        "See README: https://github.com/yvgude/lean-ctx"
      ],
      "_inferred": true
    }
  }
}

Abra Claude Desktop → Settings → Developer → Edit Config. Reinicie após salvar.

~/.cursor/mcp.json · .cursor/mcp.json

{
  "mcpServers": {
    "lean-ctx": {
      "command": "TODO",
      "args": [
        "See README: https://github.com/yvgude/lean-ctx"
      ],
      "_inferred": true
    }
  }
}

Cursor usa o mesmo esquema mcpServers que o Claude Desktop. Config de projeto vence a global.

VS Code → Cline → MCP Servers → Edit

{
  "mcpServers": {
    "lean-ctx": {
      "command": "TODO",
      "args": [
        "See README: https://github.com/yvgude/lean-ctx"
      ],
      "_inferred": true
    }
  }
}

Clique no ícone MCP Servers na barra lateral do Cline, depois "Edit Configuration".

~/.codeium/windsurf/mcp_config.json

{
  "mcpServers": {
    "lean-ctx": {
      "command": "TODO",
      "args": [
        "See README: https://github.com/yvgude/lean-ctx"
      ],
      "_inferred": true
    }
  }
}

Mesmo formato do Claude Desktop. Reinicie o Windsurf para aplicar.

~/.continue/config.json

{
  "mcpServers": [
    {
      "name": "lean-ctx",
      "command": "TODO",
      "args": [
        "See README: https://github.com/yvgude/lean-ctx"
      ]
    }
  ]
}

O Continue usa um array de objetos de servidor em vez de um map.

~/.config/zed/settings.json

{
  "context_servers": {
    "lean-ctx": {
      "command": {
        "path": "TODO",
        "args": [
          "See README: https://github.com/yvgude/lean-ctx"
        ]
      }
    }
  }
}

Adicione em context_servers. Zed recarrega automaticamente ao salvar.

claude mcp add lean-ctx -- TODO 'See README: https://github.com/yvgude/lean-ctx'

Uma linha só. Verifique com claude mcp list. Remova com claude mcp remove.

Casos de uso

Usos do mundo real: lean-ctx

How to cut your AI coding costs by 80%+ with lean-ctx

👤 Developers paying for Claude, Cursor, or Copilot API tokens ⏱ ~10 min beginner

Quando usar: Your monthly AI coding bill is growing and you want to reduce it without changing your workflow.

Pré-requisitos

lean-ctx installed — brew install lean-ctx or curl -fsSL https://leanctx.com/install.sh | sh

Fluxo

One-command setup

Run: lean-ctx setup✓ Copiado

→ Shell hooks installed, all detected editors configured automatically
Code normally for a day

Use your AI coding tool as usual — lean-ctx works transparently in the background.✓ Copiado

→ No workflow change; compression happens silently
Check savings

Run: lean-ctx gain✓ Copiado

→ Dashboard showing token savings per category (file reads, git, shell, etc.)

Resultado: Measurable token reduction (typically 60-90%) with zero workflow friction.

Armadilhas

Compressed output confuses some edge-case prompts — Use lean-ctx-off to temporarily disable, or use ctx_read with 'full' mode for specific files

Read large codebases efficiently with 8 file modes

👤 AI coding tool users working on large repos ⏱ ~5 min beginner

Quando usar: Your AI assistant wastes tokens reading entire files when it only needs the structure or signature.

Fluxo

Use map mode for overview

lean-ctx read src/main.rs -m map✓ Copiado

→ File structure at ~10% of full token cost
Use signatures mode for API

lean-ctx read src/lib.rs -m signatures✓ Copiado

→ Just function/type signatures, no bodies
Use diff mode for changes

lean-ctx read src/main.rs -m diff✓ Copiado

→ Only lines changed since last read — minimal tokens

Resultado: The AI gets exactly the context it needs at a fraction of the token cost.

Armadilhas

Aggressive mode strips too much for complex refactoring — Use 'task' mode instead — it preserves context relevant to the current task

Combine com: filesystem

Combinações

Combine com outros MCPs para 10× de alavancagem

lean-ctx + filesystem

Use lean-ctx for token-efficient reads and filesystem MCP for writes — best of both worlds

Use ctx_read to analyze the codebase structure efficiently, then use filesystem MCP to apply the refactoring changes.✓ Copiado

lean-ctx + github

lean-ctx compresses local context, GitHub MCP handles remote operations — minimizing total tokens

Use ctx_overview to understand the project, then use GitHub MCP to create a well-informed PR description.✓ Copiado

Ferramentas

O que este MCP expõe

Ferramenta	Entradas	Quando chamar	Custo
ctx_read	file: str, mode: full\|map\|signatures\|diff\|aggressive\|entropy\|task\|lines	Read a file with controlled verbosity	0 — local cached read
ctx_multi_read	files: str[], mode?: str	Read multiple files in one call	0
ctx_tree	path: str	Get project structure	0
ctx_search	query: str, path?: str	Find patterns in code	0
ctx_smart_read	file: str, intent: str	Read with task-aware filtering	0
ctx_shell	command: str	Run shell commands with output compression	0
ctx_overview	path: str	Get a high-level project overview	0
ctx_session	-	Manage context across conversation turns	0
ctx_cost	-	Track how much you've saved	0

Custo e limites

O que custa rodar

Cota de API: No external API — everything runs locally.
Tokens por chamada: That's the point: ctx_read in map mode uses ~10% of the tokens a full read would. Shell compression saves 60-95%.
Monetário: Free and open-source (MIT). Saves $30-100+/month on AI coding API costs for active developers.
Dica: Use 'map' mode as default for exploration, 'full' only when you need every line. The savings compound fast.

Segurança

Permissões, segredos, alcance

Armazenamento de credenciais: No credentials needed. Purely local tool.

Saída de dados: Zero. No telemetry, no analytics, no network requests. Everything stays on your machine.

Shell hooks modify your .zshrc/.bashrc — a backup is created at ~/.zshrc.lean-ctx.bak before any changes.
If a shell command breaks after install, run lean-ctx-off to temporarily disable hooks.

Solução de problemas

Erros comuns e correções

Shell commands produce garbled output

Run lean-ctx setup to update hooks to the latest version. If persists, run lean-ctx-off to disable temporarily.

Verificar: lean-ctx doctor

MCP server not detected by editor

Run lean-ctx setup again — it auto-configures all detected editors. For manual setup: claude mcp add lean-ctx lean-ctx

Verificar: lean-ctx doctor

Binary not found after install

Shell aliases auto-fallback safely. Re-run the install script or brew reinstall lean-ctx.

Verificar: which lean-ctx

ctx_read returns stale content

lean-ctx tracks file mtime for cache invalidation. If you edited outside the normal flow, touch the file to reset the mtime.

Verificar: lean-ctx cache --status

Alternativas

lean-ctx vs. outros

Alternativa	Quando usar	Troca
Rust Token Killer	You want a similar concept with different tradeoffs	Fewer tools (~50 patterns vs 42 tools), 3 editor support vs 24, has default-on telemetry with PII
Manual .cursorrules / CLAUDE.md context management	You prefer manual context curation	No automatic compression; no caching; more work

Mais

Recursos

📖 Leia o README oficial no GitHub

🐙 Ver issues abertas

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