OpenCode

Add Walrus Memory to OpenCode so the agent can save and recall durable facts. OpenCode uses the MCP server (the memory tools); the automatic-memory plugin hooks are available on Claude Code, Codex, Cursor, and Antigravity.

Prerequisites

• Node.js 20+
• A Walrus Memory account. The first memory tool call opens a browser sign-in (memwal_login).

Installation

Add the server to ~/.config/opencode/opencode.json as a local (stdio) MCP server:

{
  "mcp": {
    "memwal": {
      "type": "local",
      "command": ["npx", "-y", "@mysten-incubation/memwal-mcp"],
      "enabled": true
    }
  }
}

To pin a default namespace, add "environment": { "MEMWAL_NAMESPACE": "<name>" } to the server entry. Restart OpenCode, then ask the agent to run memwal_login on first use.

Available tools

Tool	Description
memwal_remember	Save a durable fact (preference, decision, constraint, identity).
memwal_remember_bulk	Save several distinct facts in one call.
memwal_recall	Semantic search across stored memories for relevant context.
memwal_analyze	Extract and save multiple facts from a passage of text.
memwal_restore	Rebuild the search index from Walrus (recovery).
memwal_health	Fast connectivity check.
memwal_login / memwal_logout	Connect or disconnect this client.

The tool descriptions tell the agent to save and recall proactively. See Reference for full parameters.

Verify

Ask the agent what MCP tools it has available. You should see the memwal_* tools. State a durable fact and confirm the agent saves it with memwal_remember.

Troubleshooting

• Tools missing: restart OpenCode after editing opencode.json.
• Not signed in: ask the agent to run memwal_login, approve in the browser, then retry.
• memwal_recall returns nothing although you saved before: run memwal_restore <namespace> to rebuild the index from Walrus.