Walrus Memory MCP

Walrus Memory MCP is a stdio Model Context Protocol server for Walrus Memory. It lets MCP clients such as Cursor, Claude Desktop, Antigravity, and Claude Code connect to the Walrus Memory relayer without manually configuring remote headers or auth tokens.

On first use, the package advertises a memwal_login tool to the MCP client. The agent can call it inline — no separate CLI command needed. The tool opens a browser-based wallet login flow and stores local credentials at ~/.memwal/credentials.json. A matching memwal_logout tool clears the saved credentials.

Quick Start

Add Walrus Memory MCP to your MCP client config:

{
  "mcpServers": {
    "memwal": {
      "command": "npx",
      "args": ["-y", "@mysten-incubation/memwal-mcp"]
    }
  }
}

Related MCP server: LedgerMem MCP Server

Login

Run the login flow manually:

npx -y @mysten-incubation/memwal-mcp login

The command opens your browser, asks you to connect your Sui wallet, and saves credentials locally.

Commands

memwal-mcp
memwal-mcp login
memwal-mcp --logout
memwal-mcp --help

Options

Use CLI flags or environment variables to override the default Walrus Memory endpoints.

Enable verbose stderr logging with MEMWAL_MCP_DEBUG=1.

Default Namespace

By default the MCP tool schemas expose an optional namespace argument and the agent has to pass it on every memwal_remember / memwal_recall / memwal_analyze call (and memwal_restore requires it). Set a default once in your client config instead:

{
  "mcpServers": {
    "memwal": {
      "command": "npx",
      "args": ["-y", "@mysten-incubation/memwal-mcp", "--namespace", "work"]
    }
  }
}

Or with an environment variable (e.g. Claude Desktop / Codex env blocks):

{
  "mcpServers": {
    "memwal": {
      "command": "npx",
      "args": ["-y", "@mysten-incubation/memwal-mcp"],
      "env": { "MEMWAL_NAMESPACE": "work" }
    }
  }
}

Resolution and precedence:

• Per-call wins: an explicit, non-empty namespace in a tool call is always used as-is — the configured default never overrides it.

• Configured default: when the agent omits namespace, the package injects --namespace (CLI) or MEMWAL_NAMESPACE (env); CLI wins over env.

• Unset: if neither is configured, the call is forwarded without a namespace and the relayer applies its own "default" namespace.

memwal_restore still advertises namespace as required in its schema, so agents normally pass one explicitly. If a default is configured and the agent calls memwal_restore without a namespace, the configured default is filled in the same way.

Verifying namespace injection

No automated test runner ships with this package (consistent with the rest of the monorepo). To verify manually:

1. Start the server pinned to a namespace and with debug logging: MEMWAL_MCP_DEBUG=1 npx -y @mysten-incubation/memwal-mcp --namespace demo-ns

2. From your MCP client, ask the agent to remember a fact without specifying a namespace, then recall it without a namespace — the recall should return that fact (both landed in demo-ns).

3. Ask the agent to recall with an explicit different namespace (e.g. other) — it should not return the fact, proving the per-call value overrode the default.

The injection itself is the pure, exported applyDefaultNamespace(msg, ns) function in src/bridge.ts if you want to assert it directly.

Environment Presets

memwal-mcp --prod
memwal-mcp --staging
memwal-mcp --local

You can also pass explicit URLs:

{
  "mcpServers": {
    "memwal": {
      "command": "npx",
      "args": [
        "-y",
        "@mysten-incubation/memwal-mcp",
        "--relayer",
        "https://relayer-staging.memory.walrus.xyz"
      ]
    }
  }
}

Credential Storage

Credentials are stored locally in ~/.memwal/credentials.json. To remove them:

npx -y @mysten-incubation/memwal-mcp --logout

License

Apache-2.0