The authoritative Open Knowledge Format v0.2 specification. Our spec section concepts restate it, one page per section; this reference points at the source of truth. (This bundle previously restated v0.1; it was re-specced to v0.2 on 2026-07-31 — see Changes from v0.1.)

Location: okf/SPEC.md in GoogleCloudPlatform/knowledge-catalog. Raw: https://raw.githubusercontent.com/GoogleCloudPlatform/knowledge-catalog/main/okf/SPEC.md

Section map

The v0.2 spec is organized as: 1. Motivation (Goals / Non-goals) · 2. Terminology · 3. Bundle Structure (3.1 Reserved filenames) · 4. Concept Documents (4.1 Frontmatter, 4.2 Body, 4.3/4.4 examples) · 5. Provenance, trust, and lifecycle (5.1 sources + credibility signals, 5.2 generated/verified, 5.3 Trust tiers, 5.4 status, 5.5 stale_after) · 6. Cross-linking and paths (6.1 Links, 6.2 Path-valued fields, 6.3 references/ convention) · 7. Actor convention · 8. Index Files · 9. Log Files · 10. Attested Computations (10.1–10.6) · 11. Conformance · 12. Versioning · 13. Changes from v0.1 · Appendix A (worked income-statement example).

Each maps to a concept under /spec.

Key takeaways

• Only type is a required field; a concept carrying just type is fully conformant.
• v0.2 makes provenance, trust, lifecycle, and attestation first-class while staying minimal — see Provenance, Trust & Lifecycle and Attested Computations.
• Two breaking changes from v0.1: timestamp → generated.at and the # Citations body list → sources frontmatter.
• index.md and log.md are still the only reserved filenames.
• Links are untyped directed edges; consumers must tolerate broken ones.
• Conformance is deliberately minimal; consumers must be tolerant.

Notes for the skills work

The spec ships with a reference agent (see OKF README) that enriches bundles from BigQuery + web crawl and visualizes them as a self-contained HTML graph. That reference agent is Python/BigQuery-specific; our portable skills target the same format but a general (any-project) workflow driven by the schema layer.

Citations

1. OKF SPEC.md — https://github.com/GoogleCloudPlatform/knowledge-catalog/blob/main/okf/SPEC.md