@mem-weave/opencode-plugin

MemWeave OpenCode plugin — registers the @mem-weave/mcp server as an MCP provider inside OpenCode, and auto-injects summary-only memory XML into the agent's system prompt at session_start, prompt_delta, and file_pack phases. Closes the progressive disclosure loop: the LLM sees summaries in the system prompt, then calls memory_expand to fetch full content.

This is the OpenCode integration half of the MemWeave stack. The complementary packages are:

• @mem-weave/server — the memory backend
• @mem-weave/mcp — the MCP server this plugin auto-registers

Install

# 1. Install the server + mcp
npm install -g @mem-weave/server @mem-weave/mcp
# 2. Install this plugin as an OpenCode plugin
npm install -g @opencode-ai/plugin   # peer dep
npm install -g @mem-weave/opencode-plugin

Then add to ~/.config/opencode/opencode.json:

{
  "$schema": "https://opencode.ai/config.json",
  "plugin": ["@mem-weave/opencode-plugin"]
}

Restart OpenCode. The plugin loads on startup and:

1. Registers mcp["memweave"] — OpenCode auto-spawns @mem-weave/mcp and the 10 memory_* tools become available to the LLM.
2. Hooks experimental.chat.system.transform — appends <memory-context> XML (summary-only) to the system prompt at every turn.
3. Hooks tool.execute.before — when the LLM calls Read/Edit/Write/Glob/Grep, queues a file_pack XML for the next system turn.

Progressive disclosure, end to end

plugin loads  →  config hook registers mcp["memweave"]
            ↓
OpenCode  →  10 memory_* tools in LLM's tool list
            ↓
LLM starts  →  system.transform injects summary-only XML
            ↓
LLM sees m_abc  →  calls memory_expand({memoryId: "m_abc"})
            ↓
MCP server  →  proxies to GET /api/v1/memories/m_abc
            ↓
LLM gets full content

The plugin itself is a thin coordinator — no business logic. All memory work happens in @mem-weave/server, surfaced via @mem-weave/mcp's 10 tools.

Environment variables

| Var | Default | Meaning | |---|---|---| | MEMWEAVE_URL | http://127.0.0.1:3131 | MemWeave server base URL | | MEMWEAVE_PLUGIN_TIMEOUT | 10000 (ms) | Per-inject-request timeout. Overridable. |

License

MIT