RFD 1124: The RFD structure gate reads a CommonMark AST
scripts/requirements.txt, .pre-commit-config.yaml, .github/workflows/checks.yml
Problem
This repository held 116 RFDs and one gate. That gate checked numbers. Nothing checked the shape of a document, so the shape stayed an agreement each writer kept from memory.
A measurement over all 116 found nine kinds of defect. The largest was 37 citations still in the old decimal form. The number gate looked for those and reported 3. An RFD wraps its prose at about 72 columns, so a citation splits across a line break, and a scan of the bytes cannot see it. That gate measured the file. The rule is about the sentence.
Decision
scripts/check-rfd-structure.py parses each README.md and DETAILS.md into a CommonMark AST and checks the document against that tree. It joins the inline text of a paragraph before it matches, so a wrapped citation is one citation. It found all 37.
Each rule ran against all 116 RFDs before it became a rule. A rule that needed an exception did not ship. The gate reads both its state list and its README line limit out of RFD 1000, so document and gate cannot drift apart. It takes one dependency, markdown-it-py, pinned. The number gate keeps numbering only, and its weaker citation scan moved here.