OKF is the Open Knowledge Format Google Cloud published in June 2026. A folder ("bundle") of Markdown files. Each file is a "concept." Each file's YAML frontmatter must carry a non-empty type. Everything else is convention. Vendor-neutral, git-friendly, agent-readable. The Obsidian CLI can read the same frontmatter with its properties: read command that a Python script or a claude-code agent can read.
We use OKF as a one-directional serialization boundary we own on both sides. myKG produces the graph and holds the typed edges. OKF projects one concept per node into a folder of Markdown files. That folder is what humans read in Obsidian and what agents read over the CLI. There is no second document to keep in sync. The concept file's frontmatter carries the typings (shuriq_rea_type, shuriq_bmc_cell). The concept file's body carries the prose that OKF's spec places relationship meaning in.
The firewall is not the format hiding anything. Protection is three things stacked. OKF's link model is too poor to carry typed edges or second-order dynamics, so a bundle is Layer 2 by construction. The exporter is a deliberate projection that picks types, allow-lists extension keys, and writes controlled prose bodies. And a resource: URI on every concept points at a rehydration endpoint we own and gate. If the exporter is careful, the bundle can ship outside the team without leaking the store.
How to apply it. Author client-bundle concepts in OKF format from day one. Use the composite typings in the frontmatter, not the prose. Let the prose describe what a reader (human or agent) sees on the page. The next post is Totem Persona, the identity layer that holds all this together across engagements.