If you are feeding Markdown notes into AI tools like Claude Code, Cursor, or Gemini CLI, Google Cloud's Open Knowledge Format (OKF) is the standard you need to know. The v0.2 specification is surprisingly lightweight: it requires only a single YAML frontmatter field, type, for a bundle to be considered conformant. Everything else is recommended or optional, designed to lower the barrier for both human authors and AI agents.

The Bare Minimum for Conformance

According to Section 4.1 of the OKF v0.2 spec, a concept document is valid if it contains a parseable YAML frontmatter block with a non-empty type value. This field accepts free text, such as policy, procedure, or Metric, without any central registry. Consumers are explicitly instructed not to reject bundles for missing optional fields, unknown type values, or broken cross-links. This flexibility ensures that existing Markdown repositories can adopt the standard without massive refactoring.

Validating Bundles with Python

For developers wanting to enforce these rules in CI pipelines, a lightweight Python script can check for the required type field and flag missing recommended attributes like title or description. The script iterates through .md files, skipping reserved filenames like index.md and log.md, and exits with a non-zero status if any file lacks a valid frontmatter block or type. This approach avoids heavy dependencies, though it notes that strict YAML parsing requires yaml.safe_load to catch malformed blocks.

Quick Checks with Grep and Yq

For faster, shell-based validation, grep can list files missing the type line using the command grep -rL --include='*.md' -E '^type: *[^ ]'. However, this may produce false positives if the string appears in the body. For accurate frontmatter-only extraction, yq (v4) offers a --front-matter=extract mode. This tool allows you to verify specific fields like .type or .description across your entire directory structure, ensuring that recommended metadata is present where it matters.

Key Takeaways

  • OKF v0.2 requires only the type field for conformance; all other fields are optional or recommended.
  • Reserved filenames index.md and log.md are exempt from standard concept document rules.
  • Consumers must accept unknown types and missing optional fields to maintain compatibility.
  • Validation can be done via simple Python scripts, grep, or yq for strict YAML parsing.

The Bottom Line

OKF v0.2 is a masterclass in pragmatic standardization, prioritizing adoption speed over rigid enforcement. By mandating only the type field, it allows teams to integrate knowledge bases with AI agents immediately while refining metadata over time.