Texio

Reliable Markdown operations for shell scripts and AI agents.

Texio extracts and surgically edits Markdown by document structure. Use it when regular expressions are unsafe and rewriting the complete file would create unnecessary changes.

grep finds text. sed changes text. Texio understands Markdown.

Extract a Markdown section

$ texio section README.md "Installation"
## Installation

brew install texio

Replace one section safely

Preview the proposed change:

texio replace README.md \
  --section "Installation" \
  --from installation.md \
  --dry-run

Apply it by replacing --dry-run with the explicit --write flag. Texio preserves content outside the selected section and refuses ambiguous heading matches.

List headings for an agent

texio headings README.md --json

[{"level":1,"title":"Texio"},{"level":2,"title":"Installation"}]

Installation

Texio requires a current stable Rust toolchain. Install the published crate:

cargo install texio-cli --locked
texio --version

To install from a checkout instead:

cargo install --path . --locked

Tagged releases also provide checksum-protected archives for Linux x86-64, Windows x86-64, Intel macOS, and Apple Silicon macOS. Download the archive and its adjacent .sha256 file from GitHub Releases, verify the checksum, then place texio (or texio.exe) on your PATH.

The Homebrew formula will be published after the first stable binary release.

Status

Texio is an early preview. The initial contract focuses on section extraction, heading discovery, and surgical replacement. CommonMark and GitHub Flavored Markdown compatibility work is ongoing.

Current parsing is powered by pulldown-cmark and supports ATX and Setext headings while ignoring heading-like text inside fenced code blocks. Replacement is atomic and preserves the target file's permissions.

See Markdown support for dialect coverage, editing guarantees, and current limitations. See the CLI contract for stdin/stdout behavior, JSON schemas, safety modes, compatibility policy, and exit codes.

Why Texio?

AI agents frequently rewrite entire Markdown files to change one section. That uses unnecessary context and can alter unrelated content. Texio provides a small, deterministic operation that is easier to review and automate.

License

MIT