feat: add Hermes Agent plugin integration

README.md

@@ -296,7 +296,7 @@ After install, **restart Claude Code**.
 
 ## Supported AI Tools
 
-RTK supports 10 AI coding tools. Each integration transparently rewrites shell commands to `rtk` equivalents for 60-90% token savings.
+RTK supports 11 AI coding tools. Each integration transparently rewrites shell commands to `rtk` equivalents for 60-90% token savings.
 
 | Tool | Install | Method |
 |------|---------|--------|
@@ -310,6 +310,7 @@ RTK supports 10 AI coding tools. Each integration transparently rewrites shell c
 | **Cline / Roo Code** | `rtk init --agent cline` | .clinerules (project-scoped) |
 | **OpenCode** | `rtk init -g --opencode` | Plugin TS (tool.execute.before) |
 | **OpenClaw** | `openclaw plugins install ./openclaw` | Plugin TS (before_tool_call) |
+| **Hermes Agent** | `cp -r hermes ~/.hermes/plugins/rtk-rewrite` | Python plugin (`pre_tool_call`) |
 | **Mistral Vibe** | Planned (#800) | Blocked on upstream BeforeToolCallback |
 
 ### Claude Code (default)
@@ -390,6 +391,15 @@ openclaw plugins install ./openclaw
 
 Plugin in `openclaw/` directory. Uses `before_tool_call` hook, delegates to `rtk rewrite`.
 
+### Hermes Agent
+
+```bash
+mkdir -p ~/.hermes/plugins/rtk-rewrite
+cp hermes/__init__.py hermes/plugin.yaml hermes/README.md ~/.hermes/plugins/rtk-rewrite/
+```
+
+Plugin in `hermes/` directory. Uses Hermes' Python `pre_tool_call` hook, delegates to `rtk rewrite`, and includes conservative Hermes-specific guards for compound commands, background calls, and PTY calls.
+
 ### Mistral Vibe (planned)
 
 Blocked on upstream BeforeToolCallback support ([mistral-vibe#531](https://github.com/mistralai/mistral-vibe/issues/531), [PR #533](https://github.com/mistralai/mistral-vibe/pull/533)). Tracked in [#800](https://github.com/rtk-ai/rtk/issues/800).

hermes/README.md

@@ -0,0 +1,170 @@
+# RTK Plugin for Hermes
+
+Hermes-specific RTK integration that intercepts `terminal` tool calls and rewrites eligible commands via `rtk rewrite` before execution.
+
+The goal is to reduce LLM token usage on common shell commands while preserving safe fallback behavior when RTK does not apply.
+
+## What it does
+
+When Hermes is about to run a `terminal` tool call, this plugin can rewrite commands such as:
+
+- `git status` -> `rtk git status`
+- `ls -la` -> `rtk ls -la`
+- `curl -fsSL https://example.com` -> `rtk curl -fsSL https://example.com`
+
+All rewrite logic lives in the RTK binary itself. This plugin is only a thin Hermes adapter.
+
+## Files
+
+- `plugin.yaml` — Hermes plugin manifest
+- `__init__.py` — plugin implementation
+- `README.md` — this file
+
+## Requirements
+
+- Hermes plugin system enabled and loading plugins from `~/.hermes/plugins/`
+- `rtk` installed and available in `PATH`
+- RTK version `>= 0.23.0`
+
+Check RTK:
+
+```bash
+which rtk
+rtk --version
+```
+
+## Installation
+
+```bash
+mkdir -p ~/.hermes/plugins/rtk-rewrite
+cp hermes/__init__.py hermes/plugin.yaml hermes/README.md ~/.hermes/plugins/rtk-rewrite/
+```
+
+Then restart Hermes.
+
+## How it works
+
+The plugin registers a Hermes `pre_tool_call` hook.
+
+On each tool call:
+1. It ignores everything except the `terminal` tool.
+2. It applies a few Hermes-side skip rules.
+3. It runs `rtk rewrite "<command>"`.
+4. If RTK returns a rewritten command with exit code `0`, the plugin replaces `args["command"]` in place.
+5. If RTK does not rewrite, times out, or fails, the original command is left unchanged.
+
+## RTK exit-code handling
+
+The plugin currently interprets RTK like this:
+
+- `0` — rewrite applied
+- `1` — no RTK equivalent; pass through unchanged
+- `2` — RTK deny rule matched; leave unchanged
+- `3` — RTK ask rule matched; leave unchanged and log the situation
+
+Why exit code `3` is not auto-rewritten:
+Hermes `pre_tool_call` can mutate tool arguments, but it does not currently provide a clean native way for this plugin to trigger an interactive user-confirmation flow. Because of that, the plugin takes the conservative route and preserves the original command.
+
+## Hermes-specific safety behavior
+
+By default, the plugin skips rewriting when:
+
+- the command already starts with `rtk`
+- the command is a compound shell expression containing:
+  - `|`
+  - `||`
+  - `&&`
+  - `;`
+  - `<<`
+- the `terminal` call has `background=true`
+- the `terminal` call has `pty=true`
+
+These defaults reduce the chance of surprising behavior in interactive or complex shell scenarios.
+
+## Configuration
+
+This plugin is configured with environment variables.
+
+### Enable or disable the plugin
+
+Default: enabled
+
+```bash
+export HERMES_RTK_ENABLED=1
+```
+
+Disable:
+
+```bash
+export HERMES_RTK_ENABLED=0
+```
+
+### Verbose logging
+
+Default: off
+
+```bash
+export HERMES_RTK_VERBOSE=1
+```
+
+When enabled, the plugin logs rewrite decisions and skip reasons.
+
+### Rewrite timeout
+
+Default: `2000` milliseconds
+
+```bash
+export HERMES_RTK_TIMEOUT_MS=2000
+```
+
+### Background-call rewriting
+
+Default: skipped
+
+```bash
+export HERMES_RTK_SKIP_BACKGROUND=1
+```
+
+Allow rewriting background terminal calls:
+
+```bash
+export HERMES_RTK_SKIP_BACKGROUND=0
+```
+
+### PTY-call rewriting
+
+Default: skipped
+
+```bash
+export HERMES_RTK_SKIP_PTY=1
+```
+
+Allow rewriting PTY terminal calls:
+
+```bash
+export HERMES_RTK_SKIP_PTY=0
+```
+
+### Cache size
+
+Default: `256`
+
+The plugin caches rewrite decisions in memory to avoid repeated `rtk rewrite` subprocess calls for the same command strings.
+
+```bash
+export HERMES_RTK_CACHE_SIZE=256
+```
+
+Disable cache:
+
+```bash
+export HERMES_RTK_CACHE_SIZE=0
+```
+
+## Operational notes
+
+- This plugin only affects the Hermes `terminal` tool.
+- It does not affect `execute_code` or other tools.
+- It is a Hermes adaptation, not the upstream OpenClaw plugin.
+- If RTK is missing or too old, the plugin disables itself safely.
+- If `rtk rewrite` hangs or errors, the original command is used.