Production-ready MCP server for PDF processing with intelligent caching.
Production-ready MCP server for PDF processing with intelligent caching.
pdf-mcp · v1.17.0
by Jztan
pdf-mcp
Surgical PDF access for AI agents — search, read, and extract without flooding context.
An MCP server that lets Claude Code and other AI agents search a PDF by meaning or keyword, read only the pages that matter, and cleanly pull out tables, images, and scanned text — even from multi-column and Japanese layouts.
mcp-name: io.github.jztan/pdf-mcp
Try it in your browser
Drop in any PDF and watch an agent skim it, search it, and read only the pages that matter — using a fraction of the tokens. 100% client-side, no install required.
Why pdf-mcp?
| Without pdf-mcp | With pdf-mcp | |
|---|---|---|
| Large PDFs | Context overflow | Chunked reading |
| Token budgeting | Guess and overflow | Estimated tokens before reading |
| Finding content | Load everything | Hybrid search (BM25 keyword + semantic) |
| Tables | Lost in raw text | Extracted and inlined per page |
| Multi-column PDFs | Columns interleaved in extracted text | Column-aware reading order (pdf-mcp[multicolumn]) |
| Vertical scripts (Japanese) | Columns scrambled / glyph soup | Geometric reorder of vertical text (tategaki / 縦書き) — search CJK with mode='semantic' (pip install 'pdf-mcp[cjk]') |
| Images | Ignored | Extracted as PNG files |
| Repeated access | Re-parse every time | SQLite cache |
| Scanned PDFs | No text extracted | OCR via Tesseract, parallelized across pages (pdf_read_pages(ocr=True)) |
| Visual content | Must describe in words | Render page as image (pdf_render_pages) |
| Tool design | Single monolithic tool | 9 specialized tools |
Features
- Hybrid search — find relevant pages with a question, not a page range. Combines BM25 keyword and semantic search via Reciprocal Rank Fusion
- Paginated reading — fetch only the pages your agent needs; large documents don't blow your context window
- OCR — scanned and image-based PDFs are fully readable and searchable via Tesseract, parallelized across pages for ~2–3x faster extraction on typical scans
- Structured extraction — tables, embedded images, and table of contents returned as structured data, not text soup
- Vertical-script reading order — Japanese tategaki (縦書き) reconstructed from glyph geometry into correct top-to-bottom, right-to-left order; article segmentation for dense magazine layouts; mojibake filtered
- Persistent cache — SQLite-backed; re-reads are instant and survive server restarts
- Secure URL fetching — HTTPS-only with SSRF protection; local network ranges are blocked
Contents
Installation
pip install pdf-mcp
For semantic search (adds fastembed and numpy, ~67 MB model download on first use):
pip install 'pdf-mcp[semantic]'
For correct reading order on multi-column PDFs (adds pymupdf4llm, which pulls pymupdf_layout/onnxruntime):
pip install 'pdf-mcp[multicolumn]'
Without it, multi-column pages fall back to positional-sort extraction, which can interleave columns.
For Japanese/Chinese/Korean PDFs (recommended — CJK search needs semantic;
extraction works without it):
pip install 'pdf-mcp[cjk]'
For OCR on scanned PDFs (requires system Tesseract):
# macOS
brew install tesseract
# Ubuntu/Debian
apt install tesseract-ocr
# Windows — download the installer from:
# https://github.com/UB-Mannheim/tesseract/wiki
# Then add the install directory to your PATH.
Quick Start
Choose your MCP client below to get started:
Claude Code
claude mcp add pdf-mcp -- pdf-mcp
Or add to ~/.claude.json:
{
"mcpServers": {
"pdf-mcp": {
"command": "pdf-mcp"
}
}
}
Claude Desktop
Add to your claude_desktop_config.json:
{
"mcpServers": {
"pdf-mcp": {
"command": "pdf-mcp"
}
}
}
Config file location:
- macOS:
~/Library/Application Support/Claude/claude_desktop_config.json - Windows:
%APPDATA%\Claude\claude_desktop_config.json
Restart Claude Desktop after updating the config.
Visual Studio Code
Requires VS Code 1.101+ with GitHub Copilot.
CLI:
code --add-mcp '{"name":"pdf-mcp","command":"pdf-mcp"}'
Command Palette:
- Open Command Palette (
Cmd/Ctrl+Shift+P) - Run
MCP: Open User Configuration(global) orMCP: Open Workspace Folder Configuration(project-specific) - Add the configuration:
{ "servers": { "pdf-mcp": { "command": "pdf-mcp" } } } - Save. VS Code will automatically load the server.
Manual: Create .vscode/mcp.json in your workspace:
{
"servers": {
"pdf-mcp": {
"command": "pdf-mcp"
}
}
}
Codex CLI
codex mcp add pdf-mcp -- pdf-mcp
Or configure manually in ~/.codex/config.toml:
[mcp_servers.pdf-mcp]
command = "pdf-mcp"
Kiro
Create or edit .kiro/settings/mcp.json in your workspace:
{
"mcpServers": {
"pdf-mcp": {
"command": "pdf-mcp",
"args": [],
"disabled": false
}
}
}
Save and restart Kiro.
Other MCP Clients
Most MCP clients use a standard configuration format:
{
"mcpServers": {
"pdf-mcp": {
"command": "pdf-mcp"
}
}
}
With uvx (for isolated environments):
{
"mcpServers": {
"pdf-mcp": {
"command": "uvx",
"args": ["pdf-mcp"]
}
}
}
Verify Installation
pdf-mcp --help
Tools
The typical pattern: call pdf_info first to plan, then pdf_search to locate — its paragraph excerpts are often enough to answer directly. Use pdf_read_pages or pdf_read_all when you need deeper context.
| Tool | What it does |
|---|---|
pdf_info |
Page count, metadata, TOC summary, scanned-page detection. Call first. |
pdf_get_toc |
Full table of contents for documents with >50 bookmarks |
pdf_read_pages |
Read specific pages or ranges; OCR-on-demand; embedded images + tables |
pdf_read_all |
Read entire document in one call (byte-capped for safety) |
pdf_render_pages |
Render pages as PNG for vision models — diagrams, handwriting, scans |
pdf_search |
Hybrid RRF search (keyword + semantic), page or section granularity, optional paragraph excerpts |
pdf_cache_stats |
Per-document cache breakdown + total size |
pdf_cache_clear |
Clear expired or all cache entries |
server_info |
Which optional features (column-aware, OCR, semantic) and config are active. Call before feature-dependent calls. |
Example prompts:
"Read the PDF at /path/to/document.pdf"
"Which pages discuss supply chain risks?"
"Find sections about the training process"
"Show me what page 5 looks like"
"OCR pages 3-5 of the scanned PDF"
See docs/tool-reference.md for the complete reference — every parameter, response shape, security contract, and example. For semantic-search model selection, see docs/embedding-models.md.
Example Workflow
For a large document (e.g., a 200-page annual report):
User: "Summarize the risk factors in this annual report"
Agent workflow:
1. pdf_info("report.pdf")
→ 200 pages, TOC shows "Risk Factors" on page 89
2. pdf_search("report.pdf", "risk factors")
→ Matches with structural paragraph excerpts — each excerpt
is the bullet, paragraph, or heading that matched, not a
fixed-width window. Often enough to answer directly.
3. If excerpts are sufficient → synthesize answer
4. If more context needed:
pdf_read_pages("report.pdf", "89-95")
→ Full page text for deeper reading
Configuration
pdf-mcp works out of the box with no configuration. To restrict which paths and URL hosts the server can access, tune cache and worker settings, or understand what's cached, see docs/configuration.md.
- Access control —
~/.config/pdf-mcp/config.tomlallow/deny rules for paths and URLs, plus response byte caps - Environment variables — cache directory, TTL, and parallel OCR/render worker count
- Caching — SQLite-backed persistence, what's cached, and invalidation
Roadmap
See ROADMAP.md for planned features and release history.
Contributing
Contributions are welcome. See docs/contributing.md for setup, checks, the coherence eval harness, and quality-loop guidelines.
Security
Found a vulnerability? See SECURITY.md for the threat model, reporting channel, and expected response timeline. Please do not open a public GitHub issue for unpatched security reports.
License
MIT — see LICENSE.
Links
Blog posts
Background, benchmarks, and design notes from building pdf-mcp:
Getting started
- How I Built pdf-mcp — The problem with large PDFs in AI agents and a working solution
- How Claude Code Actually Reads PDFs — How AI agents use pdf-mcp tools to read and navigate PDF documents
Search & retrieval
- Semantic vs Keyword Search for AI Agents — Benchmarks and a dual-search routing pattern: FTS5 for exact identifiers, embeddings for natural language
- Hybrid Search vs Query Routing for AI Agents — Why pdf-mcp uses hybrid RRF instead of query routing: benchmarks showing RRF wins across query types
- Section Chunking vs Page Chunking for AI Agents — Why section-aware search delivers full section content in one call while page-mode costs 2–6 extra tool calls per query
- Section-Level RAG: Why BM25 Beat Hybrid Search in My Benchmark — Why pdf-mcp's section-grain search is BM25-only: hybrid RRF caused a 33% lexical regression at section grain, so granularity decides the search technique
Engineering & security
- MCP Server Security: 8 Vulnerabilities — What we found when we audited an MCP server for security holes
- Your LLM Is Free QA for Your MCP Server — Four Payload UX bugs in pdf-mcp that schema tests missed but Claude Desktop surfaced during real use
