OpenCode Plugin

The OpenCode Mem-Brain plugin gives the assistant persistent memory inside OpenCode. Before every AI turn it searches your memories and injects relevant context automatically. After a successful turn it captures the conversation as a memory. No manual wiring needed.

Install

1. Install the plugin

bunx opencode-membrain@latest install

2. Set your credentials (or add to your shell profile)

export MEMBRAIN_API_KEY="mb_live_..."
export MEMBRAIN_API_URL="https://mem-brain-api-cutover-v4-production.up.railway.app"

On Windows: use $env:MEMBRAIN_API_KEY="mb_live_..." and $env:MEMBRAIN_API_URL="https://mem-brain-api-cutover-v4-production.up.railway.app" in PowerShell, or set the same variables in System Properties → Environment Variables. Git Bash / WSL can use the export lines above as-is.

3. Restart OpenCode, then initialize memory for the current project

/membrain-init

That's it. The plugin is now active.

/membrain-init stores basic project context (language, framework, repo structure) so future searches return project-aware results out of the box.

How it works

Auto-recall: before each AI turn, the plugin queries your memories with the current conversation context and injects a [MEMBRAIN CONTEXT] block into the prompt.
Auto-capture: after a successful turn, the last exchange is stored as a memory with scope and temporal tags for reliable retrieval later.
Container tagging: all plugin-written memories include a container.<tag> tag so you can search, filter, or wipe them cleanly.

Slash commands

Command	What it does
`/remember <text>`	Manually save something to memory right now
`/recall <query>`	Search memories and show results in the chat
`/recall <query> -- interpreted`	Search and return an LLM summary instead of raw results

AI tools

The plugin registers a single membrain tool with multiple modes. Examples:

Mode	Description
`add`	Store a memory; optional `ingestionScope` (tag regex for merge/link candidates only)
`search`	Semantic search; optional `keywordFilter` or `scopeRegex` (not both); `responseFormat` raw \| interpreted \| both
`traverse`	Semantic graph traversal from `startMemoryId` with a natural-language `query`
`get` / `delete` / `cleanup` / `stats` / `help`	Batch read, filtered delete, cleanup, statistics, and inline help

Configuration

Set MEMBRAIN_API_KEY and MEMBRAIN_API_URL (see install above). Optional: ~/.config/opencode/membrain.jsonc with apiKey and apiUrl.

Variable	Description
`MEMBRAIN_API_KEY`	Your `mb_live_...` API key
`MEMBRAIN_API_URL`	Base URL of your Mem-Brain API (must include `/api/v1` prefix only if your host requires it — the client appends `/api/v1`)