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Tag System

Classify and filter your knowledge

Add tags to documents for instant filtering. Automatic frontmatter extraction, hierarchical tags, and powerful AND/OR filters across CLI, Web UI, MCP, and API. Write tags back to your markdown frontmatter.

Install GNORead the docs
Use cases
Filtering large knowledge bases
Status-driven workflows
Project and domain taxonomy across notes

What it gives you

  • Auto-extract from frontmatter
  • Hierarchical tags (project/api, status/review)
  • Filter with --tags-any (OR) or --tags-all (AND)
  • Tag autocomplete in the Web UI
  • Write-back to markdown frontmatter
  • MCP tools for AI agents
  • Temporal filters with relative dates (--since, --until)

Try it yourself

Representative commands and entry points. Full reference lives in the documentation.

gno search 'query' --tags-any bug,feature
gno query 'topic' --tags-all status/active
gno tag set doc.md api,v2

Keep reading

Related features and docs.

Collections

/features/collections

Open

Note linking

/features/note-linking

Open

Advanced retrieval

/features/advanced-retrieval

Open

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