phpDocumentor vs Sphinx

phpDocumentor is a free, open-source, self-hosted tool for analyzing PHP source code and DocBlock comments to produce API documentation. It can generate UML diagrams, parse Markdown and reStructuredText, and insert API-documentation sections into reStructuredText material. The site says full-text search works offline and describes CI integration through a GitHub Action or Docker image. Installation options include Docker, Phive, and a PHAR file; standalone installation requires PHP 8.1.2 or newer plus mbstring, while PlantUML is optional. The official Docker image supplies dependencies locally. The project also offers Composer-installable components for parsing, rendering, type resolution, and PHP reflection. It runs on Linux and macOS. Its Docker Hub overview does not actively support direct Composer installation because dependency conflicts may occur. No paid plans are listed; the plan costs nothing.

Sphinx is a free Python application that generates technical documentation from structured text. Authors can use reStructuredText or MyST Markdown; Markdown requires installing MyST-Parser separately. Built-in builders produce HTML, LaTeX for PDF, ePub, manual pages, Texinfo, and plain text. References can link sections, figures, tables, citations, glossaries, and code objects within one project or across projects. The autodoc extension imports documented modules and includes material from their docstrings. Themes and extensions, both built-in and third-party, add options such as diagrams, doctests, and API documentation. Other built-in extensions provide GitHub Pages publishing, Graphviz graphs, and intersphinx links. Sphinx also supports gettext-based translation and full-text search. It can be installed through Python and platform package managers, Docker, or from source, then deployed to services such as Read the Docs, GitHub Pages, GitLab Pages, Netlify, or self-hosted servers. Its code is released under the two-clause BSD license, and the project is community supported.