Langcli

Why this agent

Langcli (langcli-com on npm; vendor site langcli.com) is an interactive AI coding assistant in the terminal. Per its upstream README: “Langcli is 100% compatible with Claude Code. Therefore, the way to use Langcli is exactly the same as that of standard Claude Code and your existing projects’ .claude or skills are all applicable to Langcli.” This means espctl wiring lands identical to Claude Code — same config file, same shape.

Prerequisites

• Node.js 20+ installed.
• Langcli installed via npm i -g langcli-com or the official install script:

  bash -c "$(curl -fsSL https://assets.langcli.com/installation/install-langcli.sh)"
  

• langcli --version succeeds.
• espctl installed somewhere stable on disk (full path needed below).
• (Optional, for remote builds) An Aegis build server URL + MCP_AUTH_SECRET.

Install snippet (or alternative)

Paste into .claude/settings.json (project root or global) — Langcli reads the same file Claude Code reads:

{
  "mcpServers": {
    "espctl": {
      "command": "/path/to/espctl",
      "args": ["mcp", "serve"],
      "cwd": "/path/to/your/esp-idf/project",
      "env": {
        "CONTROL_BASE_URL": "https://esphome.cloud",
        "MCP_AUTH_SECRET": "your-access-key"
      }
    }
  }
}

Replace:

• /path/to/espctl — full path to the espctl program on your computer.
• /path/to/your/esp-idf/project — full path to the project Langcli should work on.
• CONTROL_BASE_URL — your Aegis build server URL.
• MCP_AUTH_SECRET — your access key from the build server.

If you’ve already set up Claude Code, you’re done — Langcli reads the same config. No separate Langcli-side edit needed.

Alternative — fetch a pre-filled snippet:

Read the install://langcli resource.

First-run verification

cd /path/to/your/esp-idf/project
langcli

In the session, ask:

What espctl tools do you have?

Expected: ~40 espctl tools listed (build, doctor, store_versions, …).

Troubleshooting

• Langcli starts but no espctl tools — confirm .claude/settings.json exists in your current directory OR in ~/.claude/. Langcli uses Claude Code’s discovery rules.
• Same MCP errors as Claude Code — Langcli’s MCP runtime is Claude-Code-compatible by design; if espctl works in Claude Code but not Langcli, file an upstream issue at LangcliTeam/langcli. See also Claude Code troubleshooting.
• langcli command not found — npm i -g langcli-com installs to the global npm prefix; ensure npm bin -g is on $PATH.

Tested as-of 2026-05-19

Langcli-specific notes

• The README emphasises that “your existing projects’ .claude or skills are all applicable to Langcli.” So skills shipped with your Claude Code setup work in Langcli too — no porting.
• API key setup is via LangRouter for model-provider routing (DeepSeek, GPT, Claude, etc.). This is independent of MCP server config and orthogonal to espctl.