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+---
+name: add-rtk
+description: Install rtk token-compression proxy into agent containers. Routes Bash tool calls through rtk for 60–90% token savings on dev commands (git, cargo, pytest, docker, kubectl, etc.).
+---
+
+# Add rtk
+
+Install [rtk](https://github.com/rtk-ai/rtk) — a CLI proxy delivering 60–90% token savings on common dev commands (git, cargo, pytest, docker, kubectl, etc.) — and wire it transparently into agent containers via the Claude Code `PreToolUse` hook.
+
+## What this sets up
+
+- `rtk` binary at `~/.local/bin/rtk` on the host
+- `~/.local/bin/rtk` mounted read-only at `/usr/local/bin/rtk` inside the target agent group's containers
+- `PreToolUse` hook in the agent group's `settings.json` so every Bash call is automatically filtered through rtk — no CLAUDE.md instructions needed
+
+## Step 1 — Install rtk on the host
+
+```bash
+curl -fsSL https://raw.githubusercontent.com/rtk-ai/rtk/refs/heads/master/install.sh | sh
+```
+
+If the script put the binary elsewhere, move it:
+
+```bash
+find ~/.local ~/.cargo/bin ~/bin -name rtk 2>/dev/null
+mv "$(which rtk 2>/dev/null)" ~/.local/bin/rtk
+```
+
+Verify:
+
+```bash
+~/.local/bin/rtk --version
+chmod +x ~/.local/bin/rtk   # if needed
+```
+
+## Step 2 — Identify the target agent group
+
+```bash
+ncl groups list
+```
+
+Note the group ID (e.g. `ag-1776342942165-ptgddd`). Repeat Steps 3–5 for each group.
+
+## Step 3 — Mount rtk into the container config
+
+`additional_mounts` is a JSON column not exposed via `ncl config update`. Update it directly via the DB helper, merging with any existing mounts.
+
+Read current mounts first:
+
+```bash
+pnpm exec tsx scripts/q.ts data/v2.db \
+  "SELECT additional_mounts FROM container_configs WHERE agent_group_id = '<group-id>'"
+```
+
+Then write the merged array (include all existing entries plus the rtk entry):
+
+```bash
+pnpm exec tsx scripts/q.ts data/v2.db \
+  "UPDATE container_configs SET additional_mounts = '<merged-json>' WHERE agent_group_id = '<group-id>'"
+```
+
+The rtk entry to append: `{"hostPath":"/home/<user>/.local/bin/rtk","containerPath":"/usr/local/bin/rtk","readonly":true}`
+
+Verify:
+
+```bash
+pnpm exec tsx scripts/q.ts data/v2.db \
+  "SELECT additional_mounts FROM container_configs WHERE agent_group_id = '<group-id>'"
+```
+
+## Step 4 — Add the PreToolUse hook to settings.json
+
+Each agent group has a `settings.json` at:
+
+```
+data/v2-sessions/<group-id>/.claude-shared/settings.json
+```
+
+This file is mounted at `/home/node/.claude/settings.json` inside the container and is read by Claude Code for hooks, env, and model config.
+
+Add the `PreToolUse` entry using `jq` to merge safely:
+
+```bash
+SETTINGS="data/v2-sessions/<group-id>/.claude-shared/settings.json"
+
+jq '.hooks.PreToolUse = [{"matcher":"Bash","hooks":[{"type":"command","command":"rtk hook claude"}]}]' \
+  "$SETTINGS" > /tmp/rtk-settings.json && mv /tmp/rtk-settings.json "$SETTINGS"
+```
+
+If `PreToolUse` already exists, append instead of overwriting:
+
+```bash
+jq '.hooks.PreToolUse += [{"matcher":"Bash","hooks":[{"type":"command","command":"rtk hook claude"}]}]' \
+  "$SETTINGS" > /tmp/rtk-settings.json && mv /tmp/rtk-settings.json "$SETTINGS"
+```
+
+## Step 5 — Restart the container
+
+```bash
+ncl groups restart --id <group-id>
+```
+
+No `--message` needed — the hook is transparent and requires no agent awareness.
+
+## Verify
+
+Ask the agent to run `git status` or any other supported command. rtk intercepts it silently. Check savings with:
+
+```bash
+~/.local/bin/rtk gain
+```
+
+## Troubleshooting
+
+### `rtk: command not found` inside the container
+
+Mount wasn't applied or container wasn't restarted:
+
+```bash
+pnpm exec tsx scripts/q.ts data/v2.db \
+  "SELECT additional_mounts FROM container_configs WHERE agent_group_id = '<group-id>'"
+# Look for entry with /usr/local/bin/rtk
+ncl groups restart --id <group-id>
+```
+
+### Hook not firing
+
+Verify the hook is in `settings.json`:
+
+```bash
+jq '.hooks.PreToolUse' data/v2-sessions/<group-id>/.claude-shared/settings.json
+```
+
+If missing, re-run Step 4.
+
+### Binary won't execute — permission denied
+
+```bash
+chmod +x ~/.local/bin/rtk
+```