Agent writes its own tools on the fly: OpenCode 2 picks up a plugin without restarting

The `.opencode/plugins/writing.ts` plugin grew by 232 lines during that same session, then added another 14. The agent immediately called its new tools: `word_count` counted 1 248 words, while `reading_time` returned 6 minutes of reading.

The second version extends this trick across the agent's entire setup. A config edit, new MCP server, or fresh plugin is picked up by all open sessions at once: no quitting, no `/reload`, no prompt-cache reset.

Previously, only a restart helped. According to issue #34408 from 29.06.2026, a new skill would not appear in the list until opencode was restarted completely. The ticket was closed without a fix.

Now a skill attaches to a live session. The `bunx skills add --skill grill-me` command puts a file in `.opencode/skills/grill-me/SKILL.md`, and the session sees it immediately. The V2 docs promise the same for every watched config folder.

How to install. There is one install command: `curl -fsSL https://opencode.ai/v2/install | bash`. Also available are `brew install anomalyco/tap/opencode-v2`, `npm install -g @opencode/cli`, and the desktop app via `brew install --cask opencode-desktop`.

The first version, if installed through a package manager, must be removed manually before installation. V1 plugins do not run in V2: neither moving the file nor renaming the config entry helps. The terminal config migrates from `tui.json` to the shared `cli.json` automatically.

As of 22.09.2026, V2 is still in beta: the AUR package is explicitly named `opencode-beta`, and bun requires the `--trust` flag. The V1 branch continues to ship releases, with v1.18.32 released on 21.09.2026.

While V1 plugins do not run in V2, the extensions ecosystem lives in two branches at once.