Universal File Opener CLI MCP server

UFO CLI

Your agent. Any file. UFO gives accessible regular files useful basic information, including unfamiliar formats. Dedicated readers go deeper on supported documents, images, archives, media and text/data. Screen supported files for hidden content and privacy risks, then make targeted changes in new, reviewable copies. One offline CLI and local MCP server, with JSON receipts.

Inspection reports its coverage gaps. Basic information for an unknown file does not imply a dedicated reader, editor or security inspector for its format. File and resource limits apply.

Free for individuals and small teams. Every command and supported file type is included, with no signup or watermark. Organizations with fewer than ten people and under USD 1 million in annual revenue, including funding, qualify; any organization can evaluate it free. See the eligibility details.

Website and comparison with other agent tools: https://universalfileopener.com/cli/

Install

Native Linux x86_64 installation needs glibc 2.35 or later (Ubuntu 24.04 and Debian 12 tested). Native Alpine/musl installation is unsupported. The Java runtime is included; the container option below uses its own runtime.

curl -fsSL https://universalfileopener.com/install.sh | sh
ufo doctor
ufo skill install --agent claude-code --dir "$PWD"

install.sh downloads the app image from the latest release, checks it against the release's SHA256SUMS and installs it under ~/.local, without sudo. The same release has a Debian package (sudo apt install ./universal-file-opener1.5.1amd64.deb) and ufo-cli-1.5.1-docker.tar, an archive of the container image for offline transfer.

Container

From a directory containing report.docx, download and run the public image:

docker run --rm --network none --read-only --cap-drop ALL \
  --user "$(id -u):$(id -g)" --security-opt no-new-privileges \
  --pids-limit 128 --cpus 2 --memory 1g \
  --tmpfs /tmp:rw,nosuid,nodev,size=256m \
  --mount type=bind,src="$PWD",dst=/input,readonly \
  ghcr.io/krauqllc/ufo-cli:1.5.1 text /input/report.docx

No GitHub login is needed. The temporary mount is required. For edits, mount a separate writable output folder at /output and select a new file there. The container reads, edits and recognizes text; page rendering and Office-to-PDF conversion need the application package. For a deployment pinned to an immutable image, use the digest in the release notes.

Connect an agent

Run in the project folder. For Cursor use ufo skill install --agent cursor --dir "$PWD". For Codex use ufo skill install --agent codex --dir "$PWD" --replace; it adds or updates only the marked UFO section of the project's AGENTS.md, keeping the rest. Start a new session after installing the guide.

For an MCP client instead of the skill, ufo mcp print-config --client claude-code prints a template. Replace its executable and folder placeholders, then merge it into the client configuration. Printing does not register a server. Follow the complete setup instructions.

Get your first useful result

From a clone of this repository, with Python 3.10+ and jsonschema installed:

python3 tools/cli/first_run_demo.py --ufo "$(command -v ufo)" \
  --expect-version 1.5.1 --output first-look --mcp

The short example generates two fictional inputs. It collects basic information for an unfamiliar file, finds document properties, a reviewer comment and hidden text in a supported DOCX, and writes a clean copy. It independently checks the saved ZIP/XML bytes, original hashes, full receipt schemas and refusal to replace an existing output. Open first-look/START_HERE.txt to review the results.

Shortened. The full README is on GitHub.