diff --git a/Dockerfile.base b/Dockerfile.base
index e2c6fd3..183bad7 100644
--- a/Dockerfile.base
+++ b/Dockerfile.base
@@ -50,6 +50,7 @@ RUN apt-get update && \
     openssh-client \
     gnupg \
     jq \
+    yq \
     ripgrep \
     fd-find \
     tree \
@@ -72,6 +73,8 @@ RUN apt-get update && \
     python3-pip \
     python3-venv \
     nano \
+    pandoc \
+    graphviz \
     && ln -s /usr/bin/fdfind /usr/local/bin/fd \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists/*
@@ -295,6 +298,22 @@ RUN ARCH=$(case "${TARGETARCH}" in amd64) echo "x86_64" ;; arm64) echo "aarch64"
     rm -rf /tmp/uv-* && \
     uv --version
 
+# tealdeer — Rust port of tldr (community-maintained command examples)
+# Provides the `tldr` command; ~5 MB static binary, ~135 MB smaller than
+# the Node tldr global. Same UX as the Node version.
+ARG TEALDEER_VERSION=latest
+RUN ARCH=$(case "${TARGETARCH}" in amd64) echo "x86_64" ;; arm64) echo "aarch64" ;; *) echo "x86_64" ;; esac) && \
+    V="${TEALDEER_VERSION}" && \
+    if [ "$V" = "latest" ]; then \
+      V=$(curl -sI --retry 5 --retry-delay 5 --retry-all-errors "https://github.com/tealdeer-rs/tealdeer/releases/latest" | awk 'tolower($1)=="location:" { sub(/\r$/,"",$2); n=split($2,a,"/"); print a[n] }'); \
+    fi && \
+    V="${V#v}" && \
+    [ -n "$V" ] && \
+    echo "Installing tealdeer ${V}" && \
+    curl -fsSL --retry 5 --retry-delay 5 --retry-all-errors "https://github.com/tealdeer-rs/tealdeer/releases/download/v${V}/tealdeer-linux-${ARCH}-musl" -o /usr/local/bin/tldr && \
+    chmod +x /usr/local/bin/tldr && \
+    tldr --version
+
 # ── MemPalace — local-first AI memory system ─────────────────────────
 # Provides semantic search over conversation history via 29 MCP tools.
 # Always installed in the base (variant-independent). Set
@@ -466,6 +485,7 @@ COPY rootfs/home/developer/.gitignore_global /etc/skel-devbox/.gitignore_global
 
 # ── Entrypoint ────────────────────────────────────────────────────────
 COPY rootfs/usr/local/lib/opencode-devbox/ /usr/local/lib/opencode-devbox/
+COPY rootfs/usr/local/bin/dot-watch /usr/local/bin/dot-watch
 # Image-baked skills + harness instruction. Under /usr/local so a named volume
 # over a home dir (e.g. devbox-opencode-config on ~/.config/opencode) can't
 # shadow them; entrypoint-user.sh links them into ~/.agents/skills/ and
@@ -475,6 +495,7 @@ COPY rootfs/usr/local/share/opencode-devbox/ /usr/local/share/opencode-devbox/
 COPY entrypoint.sh /usr/local/bin/entrypoint.sh
 COPY entrypoint-user.sh /usr/local/bin/entrypoint-user.sh
 RUN chmod +x /usr/local/bin/entrypoint.sh /usr/local/bin/entrypoint-user.sh \
+    /usr/local/bin/dot-watch \
     /usr/local/lib/opencode-devbox/*.py
 
 # Start as root — entrypoint adjusts UID/GID then drops to developer
diff --git a/README.md b/README.md
index 03ab771..4f94a3e 100644
--- a/README.md
+++ b/README.md
@@ -835,7 +835,11 @@ Container (Debian trixie)
 ├── oh-my-opencode-slim (optional — multi-agent orchestration plugin, includes Bun)
 ├── AWS CLI v2 (SSO + Bedrock auth)
 ├── neovim 0.12, nano, micro, tmux, htop, bat, eza, zoxide, uv, rustup, make, gcc, g++, rsync
-├── git, git-crypt, age, gitleaks, ssh, ripgrep, fd, fzf, jq, curl, tree
+├── git, git-crypt, age, gitleaks, ssh, ripgrep, fd, fzf, jq, yq, curl, tree
+├── pandoc (Markdown↔HTML/PDF/etc. conversion)
+├── graphviz (dot diagram rendering)
+├── tldr (tealdeer — quick command examples)
+├── dot-watch (auto-render .dot to PNG on save)
 ├── Node.js (for MCP servers)
 ├── Bun (optional — included with oh-my-opencode-slim)
 ├── entrypoint.sh (UID adjustment, git config, provider setup)
diff --git a/rootfs/usr/local/bin/dot-watch b/rootfs/usr/local/bin/dot-watch
new file mode 100755
index 0000000..0b1dd23
--- /dev/null
+++ b/rootfs/usr/local/bin/dot-watch
@@ -0,0 +1,59 @@
+#!/usr/bin/env bash
+# dot-watch — auto-rerender a graphviz .dot file to PNG on every save.
+#
+# WHY THIS EXISTS
+#   pi-studio renders mermaid natively but has no graphviz/DOT renderer.
+#   Its markdown preview DOES render local image links (.png/.jpg/.gif/.webp),
+#   and the editor offers "refresh from disk". This helper closes the loop:
+#   edit a .dot file -> dot-watch regenerates <name>.png -> hit refresh in
+#   Studio to see the update. Uses mtime polling (no inotify dependency,
+#   which isn't in the trixie-slim base).
+#
+# USAGE
+#   dot-watch <file.dot> [layout] [dpi]
+#     layout: dot|neato|fdp|circo|twopi  (default: dot)
+#     dpi:    output resolution           (default: 150)
+#   env: DOT_WATCH_INTERVAL=<seconds>     poll interval (default: 1)
+#
+# EXAMPLES
+#   dot-watch /workspace/graph.dot
+#   dot-watch graph.dot neato 200
+
+set -euo pipefail
+
+SRC="${1:?usage: dot-watch <file.dot> [layout] [dpi]}"
+LAYOUT="${2:-dot}"
+DPI="${3:-150}"
+
+[[ -f "$SRC" ]] || { echo "error: no such file: $SRC" >&2; exit 1; }
+command -v "$LAYOUT" >/dev/null || { echo "error: layout engine '$LAYOUT' not found" >&2; exit 1; }
+
+OUT="${SRC%.dot}.png"
+INTERVAL="${DOT_WATCH_INTERVAL:-1}"   # seconds between polls
+ERRLOG="$(mktemp -t dot-watch.XXXXXX.err)"
+trap 'rm -f "$ERRLOG"' EXIT
+
+render() {
+    if "$LAYOUT" -Tpng -Gdpi="$DPI" "$SRC" -o "$OUT" 2> "$ERRLOG"; then
+        printf '[%s] rendered -> %s\n' "$(date +%H:%M:%S)" "$OUT"
+    else
+        printf '[%s] DOT error:\n' "$(date +%H:%M:%S)"
+        sed 's/^/    /' "$ERRLOG"
+    fi
+}
+
+# portable mtime (GNU stat, fallback to BSD stat)
+mtime() { stat -c %Y "$1" 2>/dev/null || stat -f %m "$1" 2>/dev/null; }
+
+echo "watching $SRC ($LAYOUT, ${DPI}dpi) -> $OUT  [Ctrl-C to stop]"
+render
+last="$(mtime "$SRC")"
+while true; do
+    sleep "$INTERVAL"
+    [[ -f "$SRC" ]] || continue
+    now="$(mtime "$SRC")"
+    if [[ "$now" != "$last" ]]; then
+        last="$now"
+        render
+    fi
+done
diff --git a/scripts/smoke-test.sh b/scripts/smoke-test.sh
index 41a6f7c..9c9bf96 100755
--- a/scripts/smoke-test.sh
+++ b/scripts/smoke-test.sh
@@ -131,12 +131,17 @@ run "fzf"               "fzf --version"
 run "fd"                "fd --version"
 run "rg"                "rg --version | head -1"
 run "jq"                "jq --version"
+run "yq"                "yq --version"
 run "git-crypt"         "git-crypt --version | head -1"
 run "gitleaks"          "gitleaks version"
 run "aws"               "aws --version"
 run "gitea-mcp"         "gitea-mcp --version"
 run "gosu"              "gosu --version"
 run "tmux"              "tmux -V"
+run "pandoc"            "pandoc --version | head -1"
+run "graphviz (dot)"    "dot -V"
+run "tldr (tealdeer)"   "tldr --version"
+run "dot-watch"         "test -x /usr/local/bin/dot-watch && bash -n /usr/local/bin/dot-watch && echo ok"
 
 # SSH ControlMaster baked defaults: the config file must exist (image-level)
 # and ssh -G must report ControlPath rooted at /tmp/sshcm/ for an arbitrary