feat(opencode): add v2 plugin support (--opencode-v2)

hooks/README.md

@@ -187,7 +187,7 @@ Returns `{}` when no rewrite (Cursor requires JSON for all paths).
 
 ### OpenCode (TypeScript Plugin)
 
-Mutates `args.command` in-place via the zx library:
+**v1 (default)**: Mutates `args.command` in-place via the zx `$` helper:
 
 ```typescript
 const result = await $`rtk rewrite ${command}`.quiet().nothrow()
@@ -197,6 +197,16 @@ if (rewritten && rewritten !== command) {
 }
 ```
 
+**v2**: Uses `Plugin.define` + `ctx.tool.hook("execute.before", ...)` — spawns `rtk rewrite` directly since v2 context does not provide `$`:
+
+```typescript
+const proc = spawn("rtk", ["rewrite", command])
+proc.stdout.on("data", (d) => { out += d })
+proc.on("close", () => resolve(out.trim()))
+```
+
+Installed with `rtk init -g --opencode` (v1) or `rtk init -g --opencode-v2` (v2).
+
 ### Hermes (Python Plugin)
 
 Mutates `args["command"]` in-place via the `pre_tool_call` hook:

hooks/opencode/README.md

@@ -4,8 +4,19 @@
 
 ## Specifics
 
-- TypeScript plugin using the zx library (not a shell hook)
+### OpenCode v1 (default)
+
+- TypeScript plugin using the `zx` library (bun-shell `$` helper)
 - Intercepts `tool.execute.before` events, calls `rtk rewrite` as a subprocess
 - Uses `.quiet().nothrow()` to silently ignore failures
 - Mutates `args.command` in-place if rewrite differs from original
 - Installed to `~/.config/opencode/plugins/rtk.ts` by `rtk init -g --opencode`
+
+### OpenCode v2
+
+- TypeScript plugin using the `Plugin.define` API (`@opencode-ai/plugin` v2)
+- Registers `ctx.tool.hook("execute.before", ...)` instead of returning a hooks object
+- Calls `rtk rewrite` via `child_process.spawn` (v2 context does not provide `$`)
+- Uses `spawn` + stdout capture instead of exit codes (`rtk rewrite` exits non-zero on success)
+- Mutates `event.input.command` in-place if rewrite differs from original
+- Installed to `~/.config/opencode/plugins/rtk.ts` by `rtk init -g --opencode-v2`

hooks/opencode/rtk-v2.ts

@@ -0,0 +1,45 @@
+import { Plugin } from "@opencode-ai/plugin"
+import { spawn } from "child_process"
+
+// RTK OpenCode v2 plugin — rewrites commands to use rtk for token savings.
+// Requires: rtk >= 0.23.0 in PATH.
+//
+// OpenCode 2.0 uses a new plugin API (Plugin.define + ctx.tool.hook) and does
+// not provide the v1 bun-shell `$` helper, so this variant spawns `rtk`
+// directly. `rtk rewrite` exits non-zero even on success, so we read stdout
+// from the child instead of relying on exit codes.
+//
+// This is a thin delegating plugin: all rewrite logic lives in `rtk rewrite`,
+// which is the single source of truth (src/discover/registry.rs).
+// To add or change rewrite rules, edit the Rust registry — not this file.
+
+function rtkRewrite(command: string): Promise<string> {
+  return new Promise((resolve) => {
+    const proc = spawn("rtk", ["rewrite", command])
+    let out = ""
+    proc.stdout.on("data", (d) => {
+      out += d
+    })
+    proc.on("error", () => resolve(""))
+    proc.on("close", () => resolve(out.trim()))
+  })
+}
+
+export default Plugin.define({
+  id: "rtk.rewrite",
+  setup: async (ctx) => {
+    await ctx.tool.hook("execute.before", async (event) => {
+      const tool = String(event.tool ?? "").toLowerCase()
+      if (tool !== "bash" && tool !== "shell") return
+      if (!event.input || typeof event.input !== "object") return
+
+      const command = (event.input as Record<string, unknown>).command
+      if (typeof command !== "string" || !command) return
+
+      const rewritten = await rtkRewrite(command)
+      if (rewritten && rewritten !== command) {
+        ;(event.input as Record<string, unknown>).command = rewritten
+      }
+    })
+  },
+})