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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.

1. Install and generate the snippet

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 manualprints the MCP entry to stdout instead of writing a host file. The printed block is already wrapped in mcpServers, exactly the shape Cline expects:
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).

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.

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:
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.

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.