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mcp/harbor
Gemini CLI

substrate browser for Gemini CLI

io.github.manuelinuxkr/substrate-browser

Token-first headless browser for AIs. Extracts a tiny semantic graph, cutting HTML bloat by 95%.

client:Gemini CLI transport:stdio runtime:npm

Install substrate browser in Gemini CLI

~/.gemini/settings.json · windows: %USERPROFILE%\.gemini\settings.json

Held in this page only — never stored, logged, or sent anywhere but back to your screen. 

{
  "mcpServers": {
    "substrate-browser": {
      "command": "npx",
      "args": [
        "-y",
        "substrate-browser"
      ],
      "env": {
        "SUBSTRATE_PROXY": "<SUBSTRATE_PROXY>",
        "SUBSTRATE_VIEWPORT_WIDTH": "<SUBSTRATE_VIEWPORT_WIDTH>",
        "SUBSTRATE_VIEWPORT_HEIGHT": "<SUBSTRATE_VIEWPORT_HEIGHT>"
      }
    }
  }
}

Gemini expands $VAR and ${VAR} inside env values, so a secret can live in your shell rather than this file. Gemini CLI docs

substrate browser in other clients

substrate browser MCP server