ACI family · member H · defensive publication · .haci
HACI · Human Mark DownHuman-AI Collaborative Interchange · who said what, in Markdown
Documents co-authored by a human and an AI flatten into one undifferentiated voice — you can't tell a human directive from a machine proposal from verified evidence. HACI fixes that inside the document's own syntax: two new prefix symbols and one case convention tag every line by authorial role — and a single-pass, deterministic parser reads it back with no NLP and no language model. It stays valid Markdown anywhere. The first specified member of the ACI family.
the whole grammar
!HUMANa human command — carries authority?QUESTIONa question; lowercase body = AI asks, uppercase / ?! = human asks>EVIDENCEoutput / a verified observation (Markdown blockquote)#HEADINGa section heading (Markdown native)```CODEa fenced code block (Markdown native)A…DOCfirst letter UPPERCASE → documentation (human prose)a…AIfirst letter lowercase → AI proposal / reasoning
the live parser — type, and watch it attribute
single-pass · O(n) · one regex · zero role-specific special cases
why it parses cleanly
Five normative principles: (1) human intent is explicit; (2) machine contributions are identifiable; (3) evidence is distinguishable from intent; (4) it stays valid Markdown; (5) the grammar stays minimal. The lexer is single-pass, line-by-line, no lookahead, classifying each line by priority: ! human → ? question → > evidence → code-fence toggle → # heading → the case convention → fallback. Role-tags inside a fenced block are content, not markers. It self-hosts: the v0.1 spec is written in its own format and parses correctly under its own rules — load it above.
what this is. a defensive publication under the Technical Disclosure Commons — establishing prior art for: line-prefix role symbols (! human, ? question) + a first-alphabetic-character case convention; compound prefixes (?! / !?); a single-pass fence-tracking lexer that deterministically classifies every line; a self-hosting spec; and the .haci extension. Not a patent. Distinguished from Markdown extensions (add structure, not authorship), chat role fields (stop at the API boundary), tracked-changes / git-blame (provenance external, not in-syntax), and XML/YAML (semantic but not human-readable Markdown). The reference parser hmd.py and the self-hosting spec ship in this repo.
names. HACI = Human-AI Collaborative Interchange (formal) = "Human Mark Down" (friendly) — the H member of the ACI family.
HACI · v0.1 · .haci · 2026-06-26David Lee Wise · Bridge-Burners LLC · the ACI namespace ↗