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SchemaBrain + Cline

~1 minute: install SchemaBrain, run schemabrain init --host manual, paste the printed block into Cline’s MCP settings, ask the agent about your database.
SchemaBrain is the trust and intelligence layer between Cline’s agent and your Postgres database — twelve read-only MCP tools, validated metrics, tamper-evident audit. Cline isn’t auto-wired by the activation wizard (there’s no --host cline), so you wire it with the --host manual snippet — which init prints in Cline’s exact mcpServers shape, ready to paste. Works on macOS, Linux, and Windows.

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1. Install and generate the snippet

uvx schemabrain init --host manual
# or install first: pipx install schemabrain (or: pip install schemabrain)
The wizard prompts you to pick 1. Connect my own Postgres (paste a postgresql+psycopg://... URL) or 2. Try with sample data (a 12-table SaaS fixture spins up in Docker; ~$0.03 to index). It introspects the schema, classifies columns for PII, optionally curates entities/metrics/joins, and — because you passed --host manual — prints the MCP entry to stdout instead of writing a host file. The printed block is already wrapped in mcpServers, exactly the shape Cline expects: 
{
  "mcpServers": {
    "schemabrain": {
      "command": "uvx",
      "args": [
        "schemabrain==0.6.0",
        "serve",
        "--url-env", "SCHEMABRAIN_DATABASE_URL",
        "--store-path", "/Users/you/schemabrain.db",
        "--pii-block", "credential,government_id,payment_card"
      ],
      "env": {
        "SCHEMABRAIN_DATABASE_URL": "postgresql+psycopg://user:pass@host:5432/db"
      }
    }
  }
}
Copy your printed block — the store path, env URL, and version pin are filled in for your install, so don’t copy the example above verbatim. The schemabrain==<version> pin keeps restarts reproducible; if uvx isn’t on your PATH, init emits the absolute path to your installed schemabrain entry point instead (still valid, just machine-specific).

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2. Open Cline’s MCP settings

In VS Code:
  1. Click the Cline icon in the sidebar.
  2. Click the MCP Servers icon (the stacked-server icon) at the top of the Cline panel.
  3. In the Configure tab, click Configure MCP Servers — this opens Cline’s cline_mcp_settings.json.

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3. Paste the entry

Paste the block from step 1. If cline_mcp_settings.json already lists other servers, merge just the schemabrain key into the existing mcpServers object rather than replacing the file: 
{
  "mcpServers": {
    "some-existing-server": { "...": "..." },
    "schemabrain": {
      "command": "uvx",
      "args": ["schemabrain==0.6.0", "serve", "--url-env", "SCHEMABRAIN_DATABASE_URL", "--store-path", "/Users/you/schemabrain.db", "--pii-block", "credential,government_id,payment_card"],
      "env": { "SCHEMABRAIN_DATABASE_URL": "postgresql+psycopg://user:pass@host:5432/db" }
    }
  }
}
Save the file. Cline reloads its MCP servers when the settings change; if SchemaBrain doesn’t appear in the MCP Servers panel, reload the window (Command Palette → Developer: Reload Window) — no full app restart, and nothing macOS-specific.
Optional — auto-approve the read-only tools. All twelve SchemaBrain tools are read-only (there is no write tool and no raw-SQL tool), so it’s safe to enable auto-approve for them from Cline’s MCP Servers panel if you’d rather not approve each call by hand. The PII firewall and the tamper-evident audit log still apply to every call.

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4. Ask the agent

list the entities SchemaBrain knows about
If Cline calls list_entities and reports the entities curated during init, you’re done. Otherwise run schemabrain doctor --verify for an end-to-end smoke test that doesn’t need an Anthropic key, and confirm the --store-path and SCHEMABRAIN_DATABASE_URL in your pasted entry match what init printed.