Your first plant

A plant is a git repository. cheme init writes the folders, the schemas' starting files, the agent skills and a CI workflow from the project template:

cheme init my-plant --name "Ethanol plant"   # folders, starting files, agent skills, CI
cd my-plant
git init
cheme git-setup                               # P&IDs as review text in git diffs, pre-commit hook
cheme status                                  # sheets, findings, gates, sign-offs

cheme init [DIRECTORY] [--name NAME] [--force] never overwrites an existing file without --force. cheme git-setup [--no-hook] registers the P&ID diff driver and installs the pre-commit hook that validates before each commit.

Draw, check, render

cheme sheet new P-01 --title "Feed and reaction"   # a sheet with a real title block
cheme validate                                       # P&IDs and lists, lists against P&IDs
cheme fmt                                            # canonical XML, a readable id on every object
cheme render                                         # build/P-01.svg
cheme diff main                                      # build/diff.html, changes highlighted

Every finding is one line with file:line, level, rule and subject, so a person or an agent can act on it. See P&IDs and DEXPI for the rules.

Process, layout and assessment

cheme process build      # BFD and PFD from process/materials.yaml and process/flowsheet.yaml
cheme process streams    # stream table with provenance, block balances
cheme layout build       # layout/plant-model.yaml from layout/*.yaml, the lists and the P&IDs
cheme assess mto         # material take-off of the 3D model
cheme check              # the engineering-step gates of checks/checks.yaml

Each step has a guide: process BFD/PFD, 3D layout, MTO and estimate, stages and gates.

Working with an agent

The template installs Claude Code skills in .claude/skills/ and an allowlist in .claude/settings.json. Claude Code applies that allowlist only once the folder is trusted: open it interactively once and accept the trust dialog, or run headless with --settings .claude/settings.json. See Agents and skills.