feat: add oh-my-pi (omp) as a supported agent

README.md

@@ -112,6 +112,7 @@ rtk init --agent cline          # Cline / Roo Code
 rtk init --agent kilocode       # Kilo Code
 rtk init --agent antigravity    # Google Antigravity
 rtk init --agent hermes         # Hermes
+rtk init --agent omp            # oh-my-pi (alias: oh-my-pi)
 
 # 2. Restart your AI tool, then test
 git status  # Automatically rewritten to rtk git status
@@ -352,7 +353,7 @@ rtk git status
 
 ## Supported AI Tools
 
-RTK supports 13 AI coding tools. Each integration rewrites shell commands to `rtk` equivalents for 60-90% token savings where the agent supports command interception.
+RTK supports 14 AI coding tools. Each integration rewrites shell commands to `rtk` equivalents for 60-90% token savings where the agent supports command interception.
 
 | Tool | Install | Method |
 |------|---------|--------|
@@ -367,6 +368,7 @@ RTK supports 13 AI coding tools. Each integration rewrites shell commands to `rt
 | **OpenCode** | `rtk init -g --opencode` | Plugin TS (tool.execute.before) |
 | **OpenClaw** | `openclaw plugins install ./openclaw` | Plugin TS (before_tool_call) |
 | **Hermes** | `rtk init --agent hermes` | Python plugin adapter (terminal command mutation via `rtk rewrite`) |
+| **oh-my-pi** | `rtk init --agent omp` | Extension TS (`tool_call` event) for `omp` binary |
 | **Mistral Vibe** | Planned ([#800](https://github.com/rtk-ai/rtk/issues/800)) | Blocked on upstream |
 | **Kilo Code** | `rtk init --agent kilocode` | .kilocode/rules/rtk-rules.md (project-scoped) |
 | **Google Antigravity** | `rtk init --agent antigravity` | .agents/rules/antigravity-rtk-rules.md (project-scoped) |

hooks/README.md

@@ -4,7 +4,7 @@
 
 **Deployed hook artifacts** — the actual files installed on user machines by `rtk init`. These are shell scripts, TypeScript plugins, and rules files that run outside the Rust binary. They are **thin delegates**: parse agent-specific JSON, call `rtk rewrite` as a subprocess, format agent-specific response. Zero filtering logic lives here.
 
-Owns: per-agent hook scripts and configuration files for 9 supported agents (Claude Code, Copilot, Cursor, Cline, Windsurf, Codex, OpenCode, Hermes, Pi).
+Owns: per-agent hook scripts and configuration files for 10 supported agents (Claude Code, Copilot, Cursor, Cline, Windsurf, Codex, OpenCode, Hermes, Pi, oh-my-pi).
 
 Does **not** own: hook installation/uninstallation (that's `src/hooks/init.rs`), the rewrite pattern registry (that's `discover/registry`), or integrity verification (that's `src/hooks/integrity.rs`).
 
@@ -41,6 +41,7 @@ Each agent subdirectory has its own README with hook-specific details:
 - **[`codex/`](codex/README.md)** — Awareness document, `AGENTS.md` integration, `$CODEX_HOME` or `~/.codex/` location
 - **[`opencode/`](opencode/README.md)** — TypeScript plugin, `zx` library, `tool.execute.before` event, in-place mutation
 - **[`pi/`](pi/README.md)** — TypeScript extension, `tool_call` event, `isToolCallEventType` guard, in-place mutation, `~/.pi/agent/extensions/`
+- **[`omp/`](omp/README.md)** — TypeScript extension for `oh-my-pi` (`@oh-my-pi/pi-coding-agent`, binary `omp`); `tool_call` event, `~/.omp/agent/extensions/`
 - **[`hermes/`](hermes/README.md)** — Python plugin, `pre_tool_call` hook, in-place terminal command mutation
 
 ## Supported Agents
@@ -57,6 +58,7 @@ Each agent subdirectory has its own README with hook-specific details:
 | Codex CLI | AGENTS.md / instructions | Prompt-level guidance | N/A |
 | OpenCode | TypeScript plugin (`tool.execute.before`) | In-place mutation | Yes |
 | Pi | TypeScript extension (`tool_call` event) | In-place mutation | Yes |
+| oh-my-pi | Extension TS (`tool_call` event) | In-place mutation | Yes |
 | Hermes | Python plugin (`pre_tool_call`) | In-place mutation | Yes |
 
 ## JSON Formats by Agent
@@ -241,7 +243,7 @@ New integrations must follow the [Exit Code Contract](#exit-code-contract) and [
 | Tier | Mechanism | Maintenance | Examples |
 |------|-----------|-------------|----------|
 | **Full hook** | Shell script or Rust binary, intercepts commands via agent's hook API | High — must track agent API changes | Claude Code, Cursor, Copilot, Gemini |
-| **Plugin** | TypeScript/JS/Python plugin in agent's plugin system | Medium — agent manages loading | OpenCode, Hermes, Pi |
+| **Plugin** | TypeScript/JS/Python plugin in agent's plugin system | Medium — agent manages loading | OpenCode, Hermes, Pi, oh-my-pi |
 | **Rules file** | Prompt-level instructions the agent reads | Low — no code to break | Cline, Windsurf, Codex |
 
 ### Eligibility

hooks/omp/README.md

@@ -0,0 +1,63 @@
+# oh-my-pi Hooks
+
+> Part of [`hooks/`](../README.md) — see also [`src/hooks/`](../../src/hooks/README.md) for installation code
+
+This integration is for `oh-my-pi` (`@oh-my-pi/pi-coding-agent`, binary `omp`). For `@earendil-works/pi-coding-agent` (binary `pi`), see [`../pi/`](../pi/).
+
+## Design Intent
+
+RTK's oh-my-pi extension is a **rewrite-only token optimizer**. It mutates bash commands to their
+`rtk`-prefixed equivalents, saving 60–90% context tokens.
+
+**Permission gating is intentionally out of scope.** RTK does not block, confirm, or audit
+commands — that concern belongs to a dedicated permission extension (e.g. one that gates
+`rm -rf`, `sudo`, etc.). This separation keeps RTK's hook fast, predictable, and composable
+with other oh-my-pi extensions.
+
+## Specifics
+
+- TypeScript extension using oh-my-pi's `ExtensionAPI` (not a shell hook, no `zx` dependency)
+- Subscribes to `tool_call` event, narrows to `bash` tool via `isToolCallEventType`
+- Calls `rtk rewrite` via `pi.exec`; mutates `event.input.command` in-place if rewrite differs
+- All error paths return `undefined` (pass through); RTK never blocks execution
+- Version guard at load time: checks `rtk >= 0.40.0`; warns and registers no-op if too old or missing
+- Installed to `.omp/extensions/rtk.ts` by `rtk init --agent omp` (project-local) or `~/.omp/agent/extensions/rtk.ts` by `rtk init --agent omp --global`
+
+## Uninstall
+
+```bash
+# Remove project-local install (run from the project root)
+rtk init --uninstall --agent omp
+# → removes .omp/extensions/rtk.ts
+
+# Remove global install
+rtk init --uninstall --agent omp --global
+# → removes ~/.omp/agent/extensions/rtk.ts
+```
+
+Uninstall is idempotent — re-running when nothing is installed is a no-op.
+Only the extension file is managed by install/uninstall.
+
+## Testing
+
+```bash
+# Load the extension directly without installing
+omp -e ./hooks/omp/rtk.ts
+
+# Verify rewrites are active — ask the agent to run a command, then check history
+rtk gain --history   # should show rtk-prefixed commands with savings %
+
+# Test RTK_DISABLED passthrough
+RTK_DISABLED=1 omp -e ./hooks/omp/rtk.ts
+# → commands pass through unchanged; no rewrites in rtk gain --history
+
+# Test version guard — temporarily shadow rtk with a stub that prints "rtk 0.39.0"
+# → extension logs a warning at startup and registers a no-op; omp starts normally
+```
+
+## Design Notes
+
+- All filtering logic lives in `rtk rewrite` (the Rust registry), not in this file
+- Exit codes 0 and 3 both mean "rewrite and allow"; they are handled identically
+- Uses `pi.exec` for subprocess management — consistent with oh-my-pi's extension API
+- oh-my-pi reuses the same `PI_CODING_AGENT_DIR` environment variable as the upstream pi integration; the default base directory differs (`.omp/agent` vs `.pi/agent`)

hooks/omp/rtk.ts

@@ -0,0 +1,82 @@
+// RTK oh-my-pi extension - rewrites bash commands to use rtk for token savings.
+// For oh-my-pi (`@oh-my-pi/pi-coding-agent`, binary: `omp`).
+// Distinct from the @earendil-works/pi-coding-agent integration in hooks/pi/.
+// Requires: rtk >= 0.40.0 in PATH.
+//
+// This is a thin delegating extension: 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.
+//
+// Exit code contract for `rtk rewrite`:
+//   0 + stdout  Rewrite found -> mutate command
+//   1           No RTK equivalent -> pass through unchanged
+//   3 + stdout  Rewrite (advisory) -> mutate command
+
+import type { ExtensionAPI } from "@oh-my-pi/pi-coding-agent"
+import { isToolCallEventType } from "@oh-my-pi/pi-coding-agent"
+
+const REWRITE_TIMEOUT_MS = 2_000
+const MIN_SUPPORTED_RTK_MINOR = 40
+
+// Parse "X.Y.Z" semver, return [major, minor, patch] or null.
+function parseSemver(raw: string): [number, number, number] | null {
+  const m = raw.trim().match(/(\d+)\.(\d+)\.(\d+)/)
+  if (!m) return null
+  return [parseInt(m[1], 10), parseInt(m[2], 10), parseInt(m[3], 10)]
+}
+
+// Calls `rtk rewrite`; returns the rewritten command or null (pass through).
+async function rewriteCommand(
+  pi: ExtensionAPI,
+  cmd: string,
+  signal?: AbortSignal
+): Promise<string | null> {
+  const result = await pi.exec("rtk", ["rewrite", cmd], {
+    timeout: REWRITE_TIMEOUT_MS,
+    signal,
+  })
+  if (result.killed) return null
+  if (result.code !== 0 && result.code !== 3) return null
+  return result.stdout.trim() || null
+}
+
+export default async function (pi: ExtensionAPI) {
+  // Probe rtk version at load time; disables extension if missing or too old.
+  const ver = await pi.exec("rtk", ["--version"], { timeout: REWRITE_TIMEOUT_MS })
+  if (ver.code !== 0) {
+    console.warn("[rtk] rtk binary not found in PATH - extension disabled")
+    return
+  }
+
+  // Warn and bail if rtk predates the minimum supported version.
+  const parsed = parseSemver(ver.stdout.replace(/^rtk\s+/, ""))
+  if (parsed) {
+    const [major, minor] = parsed
+    if (major === 0 && minor < MIN_SUPPORTED_RTK_MINOR) {
+      console.warn(`[rtk] rtk ${ver.stdout.trim()} is too old (need >= 0.${MIN_SUPPORTED_RTK_MINOR}.0) - extension disabled`)
+      return
+    }
+  }
+
+  pi.on("tool_call", async (event, ctx) => {
+    try {
+      if (!isToolCallEventType("bash", event)) return
+
+      const cmd = event.input.command
+      if (typeof cmd !== "string" || cmd.trim() === "") return
+
+      if (cmd.startsWith("rtk ")) return
+      if (process.env.RTK_DISABLED === "1") return
+
+      // Delegate to RTK.
+      const rewritten = await rewriteCommand(pi, cmd, ctx.signal)
+      if (rewritten && rewritten !== cmd) {
+        event.input.command = rewritten
+      }
+    } catch (err) {
+      // Fail open: never block execution on an unexpected error.
+      console.warn("[rtk] unexpected error in tool_call handler; passing through command", err)
+      return
+    }
+  })
+}

src/hooks/constants.rs

@@ -34,6 +34,15 @@ pub const PI_EXTENSIONS_SUBDIR: &str = "extensions";
 pub const PI_PLUGIN_FILE: &str = "rtk.ts";
 pub const PI_CODING_AGENT_DIR_ENV: &str = "PI_CODING_AGENT_DIR";
 
+// oh-my-pi (`@oh-my-pi/pi-coding-agent`, binary `omp`).
+// Distinct from the PI_* constants above which target `@earendil-works/pi-coding-agent`.
+// Both integrations share the PI_CODING_AGENT_DIR override env (the oh-my-pi runtime
+// reads the same variable); only the default dirname differs.
+pub const OMP_DIR: &str = ".omp/agent";
+pub const OMP_LOCAL_DIR: &str = ".omp";
+pub const OMP_EXTENSIONS_SUBDIR: &str = "extensions";
+pub const OMP_PLUGIN_FILE: &str = "rtk.ts";
+
 pub const HERMES_DIR: &str = ".hermes";
 pub const HERMES_PLUGINS_SUBDIR: &str = "plugins";
 pub const HERMES_PLUGIN_NAME: &str = "rtk-rewrite";