OpenCode Plugin for mem9

Persistent memory for OpenCode.

This package has two entrypoints:

• a server plugin for recall, auto-ingest, and memory tools
• a TUI plugin for interactive setup inside OpenCode

Quick Start

1. Install mem9 once at user scope

opencode plugin --global @mem9/opencode

That adds @mem9/opencode to these files:

macOS/Linux:

• ~/.config/opencode/opencode.json
• ~/.config/opencode/tui.json

Windows:

• %APPDATA%\\opencode\\opencode.json
• %APPDATA%\\opencode\\tui.json

mem9 works best with one global plugin install plus project mem9.json overrides. OpenCode merges plugin lists across scopes, so one install keeps recall, ingest, and tools predictable.

2. Restart OpenCode and run /mem9-setup

/mem9-setup is the main entrypoint for:

• shared mem9 credentials
• OpenCode mem9 settings

When no usable profile exists, it shows two actions:

• Get a mem9 API key automatically
• Add an existing mem9 API key

When usable profiles already exist, it shows four actions:

• Get a mem9 API key automatically
• Add an existing mem9 API key
• Use an existing mem9 profile in a scope
• Adjust scope settings

The last two actions do different things:

• Use an existing mem9 profile in a scope changes which profile a user or project scope uses
• Adjust scope settings changes debug, defaultTimeoutMs, and searchTimeoutMs for a user or project scope

3. Add project overrides only when you need them

Keep the plugin install global. Use <project>/.opencode/mem9.json when one repository needs a different profile, debug flag, or timeout.

Example:

{
  "schemaVersion": 1,
  "profileId": "default",
  "debug": false,
  "defaultTimeoutMs": 8000,
  "searchTimeoutMs": 15000
}

Where mem9 stores data

• Shared credentials: macOS/Linux: $HOME/.mem9/.credentials.json Windows: %USERPROFILE%\\.mem9\\.credentials.json
• Global mem9 config: macOS/Linux: ~/.config/opencode/mem9.json Windows: %APPDATA%\\opencode\\mem9.json
• Project mem9 override: all platforms: <project>/.opencode/mem9.json
• Debug logs: macOS/Linux: ~/.local/share/opencode/plugins/mem9/log/YYYY-MM-DD.jsonl Windows: %LOCALAPPDATA%\\opencode\\plugins\\mem9\\log\\YYYY-MM-DD.jsonl

MEM9_HOME defaults to $HOME/.mem9 on macOS/Linux and %USERPROFILE%\\.mem9 on Windows.

Credentials File

Shared credentials live in:

$MEM9_HOME/.credentials.json

Example:

{
  "schemaVersion": 1,
  "profiles": {
    "default": {
      "label": "Personal",
      "baseUrl": "https://api.mem9.ai",
      "apiKey": "..."
    }
  }
}

profiles stores credentials only.

OpenCode mem9 Config

User and project mem9 config use the same schema:

{
  "schemaVersion": 1,
  "profileId": "default",
  "debug": false,
  "defaultTimeoutMs": 8000,
  "searchTimeoutMs": 15000
}

Field meanings:

• profileId: which shared profile this scope should use
• debug: enable redacted JSONL debug logs
• defaultTimeoutMs: request timeout for normal mem9 calls
• searchTimeoutMs: request timeout for recall search

Project config overrides user config for the current repository.

Runtime Overrides

These environment variables still override disk config at runtime:

• MEM9_API_KEY
• MEM9_API_URL
• MEM9_DEBUG
• MEM9_HOME

Legacy compatibility:

• MEM9_TENANT_ID

MEM9_TENANT_ID is treated as the API key source for older setups.

Upgrading

OpenCode caches npm plugins by package specifier. When config points at @mem9/opencode, OpenCode resolves it as @mem9/opencode@latest.

Upgrade flow:

1. Quit OpenCode.
2. Delete the cached folder that matches the installed specifier. macOS/Linux default: ~/.cache/opencode/packages/@mem9/opencode@latest Windows default: %LOCALAPPDATA%\\opencode\\packages\\@mem9\\opencode@latest If you pinned an exact version such as @mem9/[email protected], delete that exact folder name instead.
3. Run:

opencode plugin --force --global @mem9/opencode

4. Restart OpenCode.

For prerelease testing, install an explicit npm specifier such as @mem9/opencode@rc or an exact version.

What the Plugin Does

The server plugin does three things:

• recalls relevant mem9 memories before each chat turn
• exposes mem9 memory tools inside OpenCode
• starts best-effort background smart ingest when the session becomes idle and when compaction begins

Hook Flow

OpenCode integration uses four runtime hooks:

| Hook | What mem9 does | | --- | --- | | chat.message | Captures the latest real user prompt and updates in-memory session state. | | experimental.chat.system.transform | Searches mem9 with the captured prompt and injects a <relevant-memories> block. | | event with session.idle | Starts a best-effort background smart-ingest pass for the recent transcript window. | | experimental.session.compacting | Pushes a compaction hint and starts another best-effort background smart-ingest pass. |

Recall

The plugin captures the latest real user prompt from chat.message, cleans it, bounds it, and injects a formatted recall block during experimental.chat.system.transform.

Auto-ingest

The plugin ingests from two points:

• session.idle
• experimental.session.compacting

Both paths fetch up to 24 recent session messages, keep real text-only user and assistant turns, strip injected memory blocks, and upload the last 12 cleaned messages in the background.

Identical transcripts are deduped per in-memory session state, so a matching idle ingest and compaction ingest share one upload while that session state stays warm.

Two timing details matter:

• hook completion happens before the background upload finishes
• the dedupe window is in-memory and TTL-bound to about 15 minutes, so restart or cache expiry can upload the same transcript again

Tools

The plugin registers these tools:

• memory_store
• memory_search
• memory_get
• memory_update
• memory_delete

Troubleshooting

• Setup pending means the plugin could not find a usable runtime identity. Run /mem9-setup, add MEM9_API_KEY, or point the active mem9.json scope at a profile with a non-empty apiKey.
• If /mem9-setup is missing, confirm @mem9/opencode is listed in your global tui.json.
• If recall or tools work in one project and not another, check whether the project has its own .opencode/mem9.json override.
• If recall, auto-ingest, or debug logs appear to run twice, check for duplicate plugin registration across user scope, project scope, npm, or local file paths.
• If the selected profile exists but has no apiKey, update that profile in $MEM9_HOME/.credentials.json.
• If debug logging is enabled and no file appears, confirm OpenCode can write to its state directory.