Janusmcp MCP server

JanusMCP

One credential broker. Every account. From the CLI or MCP. Multi-account tool access for AI agents, with credentials kept local.

One-click buttons require the npm package to be published. See RELEASING.md.

The problem

If you work with more than one company, you use the same MCP server (Supabase, GitHub, Slack…) with different identities — a different account, email and token per client. Today most LLM clients hold one account at a time per connector: to switch client you disconnect, reconnect, and redo the OAuth login. Every time.

The MCP protocol has no notion of "account": one session = one identity = one set of credentials. JanusMCP fills that gap.

What it does

JanusMCP is a local multi-account tool broker for AI agents. It can be used directly from the CLI or as an MCP server in front of the real upstream servers:

(code-execution mode): janusmcp tools / schema / call invoke tools on demand, with no bulk tool definitions loaded upfront.

• Add N accounts once for the same service and keep them all available.
• Switch identity without reconnecting — no re-login, no fiddling with config.
• Works with any LLM client — it just speaks standard MCP (stdio + Streamable HTTP).
• Works without an MCP session too — agents can drive it directly from the CLI

• Runs locally — your machine, your keychain, your control.
• Keeps the context clean — it exposes only the active account's tools, not N×tools.

┌─────────────────────────────┐   ┌─ Supabase (Client A)
LLM client ─MCP─▶│   JanusMCP broker           │─▶ ├─ Supabase (Client B)
(Claude/GPT/     │   active-account · vault ·  │   ├─ GitHub  (Client A)
 Gemini/…)       │   per-session scoping       │   └─ …
                 └─────────────────────────────┘

You drive it with three control tools that appear in any client: januslistaccounts, janususeaccount, janus_whoami.

Choose your mode

Use from the CLI — Claude Code, Codex, Cursor, scripts

npm install -g @bayway/janusmcp
janusmcp tools
janusmcp schema list_tables
janusmcp call list_tables --args '{"schemas":["public"]}' --json --timeout 30s

The CLI discovers schemas only when needed, accepts JSON through --args or stdin, supports explicit accounts/profiles, and provides stable exit codes. See the CLI guide and copyable agent instructions.

Connect over MCP — desktop and chat clients

npx @bayway/janusmcp serve
# or configure a supported client automatically:
janusmcp install claude-desktop

Shortened. The full README is on GitHub.