feat: agent skills runtime for LibreChat agents

Dockerfile

@@ -226,6 +226,15 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     binutils \
     && rm -rf /var/lib/apt/lists/*
 
+# ============================================
+# Document processing: LibreOffice, qpdf, fonts
+# ============================================
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    libreoffice-writer libreoffice-calc libreoffice-core libreoffice-common \
+    fonts-liberation fonts-dejavu-core fonts-noto-core \
+    qpdf \
+    && rm -rf /var/lib/apt/lists/*
+
 # ============================================
 # Sandbox directory structure
 # ============================================
@@ -288,6 +297,7 @@ RUN --mount=type=cache,target=/root/.cache/pip \
 
 COPY src/ /app/src/
 COPY dashboard/ /app/dashboard/
+COPY skills/ /opt/skills/
 
 RUN find / -path /proc -prune -o -path /sys -prune -o \
     \( -perm -4000 -o -perm -2000 \) -type f -exec chmod u-s,g-s {} + 2>/dev/null || true

docker/nsjail-base.cfg

@@ -211,6 +211,41 @@ mount {
     mandatory: false
 }
 
+# Agent skills (DOCX, XLSX, etc.)
+mount {
+    src: "/opt/skills"
+    dst: "/opt/skills"
+    is_bind: true
+    rw: false
+    mandatory: false
+}
+
+# LibreOffice shared resources
+mount {
+    src: "/etc/libreoffice"
+    dst: "/etc/libreoffice"
+    is_bind: true
+    rw: false
+    mandatory: false
+}
+
+# Font configuration
+mount {
+    src: "/etc/fonts"
+    dst: "/etc/fonts"
+    is_bind: true
+    rw: false
+    mandatory: false
+}
+
+mount {
+    src: "/usr/share/fonts"
+    dst: "/usr/share/fonts"
+    is_bind: true
+    rw: false
+    mandatory: false
+}
+
 # Writable tmpfs for temporary files
 mount {
     dst: "/tmp"

docker/requirements/nodejs.txt

@@ -33,3 +33,5 @@ zod
 handlebars
 cheerio
 marked
+docx
+pptxgenjs

docker/requirements/python-documents.txt

@@ -2,14 +2,16 @@
 
 # PDF
 PyPDF2>=3.0
-pdfminer.six>=20221105
-pdfminer>=20191125
+pypdf>=4.0
+pdfplumber>=0.10
+pdfminer.six>=20231228
 pdf2image>=1.16
 reportlab>=4.0
 
 # Office documents
 python-docx>=1.1
 python-pptx>=0.6
+markitdown[pptx]>=0.1
 mammoth>=1.6
 docx2txt>=0.8
 docx2python>=2.0

docs/AGENT_SKILLS.md

@@ -0,0 +1,136 @@
+# Agent Skills Runtime
+
+This document describes the agent skill dependencies embedded in the LibreCodeInterpreter Docker image to support specialized LibreChat agents.
+
+## Overview
+
+The image includes pre-installed skills, system binaries, and Python/Node packages required by the following LibreChat agents:
+
+| Agent | Key Dependencies | Skills Directory |
+|-------|-----------------|-----------------|
+| Word DOCX "Complete" | LibreOffice, pandoc, python-docx, lxml | `/opt/skills/docx/` |
+| PowerPoint PPTX | LibreOffice Impress, python-pptx, pptxgenjs, markitdown | `/opt/skills/pptx/` |
+| Excel/XLSX | LibreOffice Calc, openpyxl, pandas | `/opt/skills/xlsx/` |
+| PDF | qpdf, pdfplumber, pypdf, tesseract-ocr, poppler-utils | — |
+| Quick Edits | ffmpeg, ffprobe, Pillow | — |
+| Data Analysis & Visualization | pandas, numpy, matplotlib, seaborn, scipy | — |
+| YouTube Assistant | No special system deps | — |
+
+## Skills Directory
+
+Skills are embedded in the image at `/opt/skills/` and mounted read-only inside nsjail sandboxes.
+
+```
+/opt/skills/
+├── docx/
+│   ├── SKILL.md
+│   └── scripts/
+│       ├── accept_changes.py     # Accept tracked changes via LibreOffice
+│       ├── comment.py            # Add/reply comments in unpacked DOCX XML
+│       ├── tracked_replace.py    # Find-and-replace with redline markup
+│       ├── office/
+│       │   ├── soffice.py        # LibreOffice helper (sandbox-aware)
+│       │   ├── unpack.py         # Unpack DOCX/PPTX/XLSX to XML
+│       │   ├── pack.py           # Repack XML to DOCX with validation
+│       │   ├── validate.py       # XSD + redlining validation
+│       │   ├── helpers/
+│       │   │   ├── merge_runs.py
+│       │   │   └── simplify_redlines.py
+│       │   ├── validators/
+│       │   │   ├── base.py
+│       │   │   ├── docx.py
+│       │   │   ├── pptx.py
+│       │   │   └── redlining.py
+│       │   └── schemas/          # XSD schemas (ISO 29500, ECMA, Microsoft)
+│       └── templates/            # XML templates for comments
+├── pptx/
+│   ├── SKILL.md
+│   ├── editing.md                # Template-based editing workflow
+│   ├── pptxgenjs.md              # PptxGenJS tutorial (create from scratch)
+│   └── scripts/
+│       ├── add_slide.py          # Duplicate slide or create from layout
+│       ├── clean.py              # Remove orphaned slides/media
+│       ├── thumbnail.py          # Visual thumbnail grid for templates
+│       └── office/ → ../../docx/scripts/office  (symlink, shared)
+└── xlsx/
+    ├── SKILL.md
+    └── scripts/
+        ├── recalc.py             # Formula recalculation via LibreOffice
+        └── office/
+            └── soffice.py        # LibreOffice helper
+```
+
+## Environment Variable
+
+The `SKILLS_ROOT` environment variable is set to `/opt/skills` in all sandbox executions. Agents reference scripts via `$SKILLS_ROOT/docx/scripts/...`.
+
+## System Dependencies Added for Agents
+
+| Package | Purpose | Used By |
+|---------|---------|---------|
+| `libreoffice-writer` | DOCX conversion, accept tracked changes | Word, XLSX agents |
+| `libreoffice-calc` | Formula recalculation | XLSX agent |
+| `libreoffice-core`, `libreoffice-common` | Shared LibreOffice runtime | Word, XLSX agents |
+| `fonts-liberation`, `fonts-dejavu-core`, `fonts-noto-core` | Document rendering fonts | Word, XLSX, PDF agents |
+| `qpdf` | PDF manipulation, linearization, repair | PDF agent |
+| `pdfplumber` (Python) | PDF table extraction | PDF agent |
+| `pypdf` (Python) | Modern PDF library | PDF agent |
+| `docx` (Node.js) | Word document generation from JS | Word agent |
+| `markitdown[pptx]` (Python) | PPTX/document to markdown conversion | PPTX agent |
+| `pptxgenjs` (Node.js) | PowerPoint generation from JS | PPTX agent |
+
+Already present in base image: `pandoc`, `poppler-utils` (pdftoppm), `tesseract-ocr`, `ffmpeg`, `python-docx`, `python-pptx`, `openpyxl`, `defusedxml`, `matplotlib`, `seaborn`, `pandas`, `numpy`, `scipy`, `Pillow`, `pdf-lib` (Node), `xlsx`/`exceljs` (Node).
+
+## nsjail Sandbox Visibility
+
+The following mounts are added to `docker/nsjail-base.cfg` to make skills and LibreOffice accessible inside sandboxes:
+
+| Host Path | Sandbox Path | Access | Purpose |
+|-----------|-------------|--------|---------|
+| `/opt/skills` | `/opt/skills` | read-only | Skill scripts |
+| `/etc/libreoffice` | `/etc/libreoffice` | read-only | LO configuration |
+| `/etc/fonts` | `/etc/fonts` | read-only | Font configuration |
+| `/usr/share/fonts` | `/usr/share/fonts` | read-only | Font files |
+
+LibreOffice also needs a writable profile directory; the `soffice.py` helper creates one under `/tmp/` at runtime.
+
+## LibreChat Configuration
+
+Point LibreChat to this instance with these environment variables:
+
+```env
+# In LibreChat's .env
+LIBRECHAT_CODE_API_KEY=your-api-key-here
+LIBRECHAT_CODE_BASEURL=http://your-host:8000
+```
+
+## Smoke Tests
+
+Run inside the container:
+
+```bash
+docker exec <container> bash /app/tests/smoke/test_agent_skills.sh
+```
+
+Tests verify: binary availability, Python/Node package imports, functional DOCX/XLSX/PDF/media operations, skills directory structure, and matplotlib headless rendering.
+
+## tracked_replace.py
+
+Custom implementation for Word tracked changes (redlines). Not part of the upstream Anthropic skill.
+
+Usage:
+```bash
+python $SKILLS_ROOT/docx/scripts/tracked_replace.py UNPACKED_DIR \
+    --old "original text" --new "replacement text" \
+    [--old "another" --new "replacement"] \
+    [--first] \
+    [--author "AI-Agent"]
+```
+
+Features:
+- Proper `<w:del>`/`<w:ins>` XML markup
+- Preserves `<w:rPr>` formatting
+- Multiple replacement pairs in one pass
+- `--first` flag for single occurrence
+- Configurable author (default: `AI-Agent`)
+- Skips zones already under tracked changes