Tag notes

Tags group notes across folders. A note can carry any number, and they're written in the note itself, so they travel with it: an Obsidian vault you sync into Treehouse keeps its tags.

Add a tag

Write it in the note's text, or list it in the note's front matter. Both count the same.

---
tags: [planning, product]
---

Ship the beta by Friday. #launch/beta

That note has three tags: planning, product and launch/beta.

• In the text, a tag is # and a word, written after a space or at the start of a line: #planning. It can hold letters, numbers, -, _ and /, but not only numbers (#2026 isn't a tag).
• In front matter, tags: takes a list (tags: [planning, product]) or names separated by commas (tags: planning, product). The # is optional there.

Capitals don't matter: #Planning and #planning are the same tag.

A # in a heading (# Title), in the middle of a word or address (page#section), or inside code isn't a tag.

Nest tags

A / puts one tag under another. #launch/beta is also filed under #launch, so looking for launch finds notes tagged launch/beta as well.

Find notes by tag

Type # in the sidebar's search box. It shows the tags in use, each with the number of notes carrying it, and lists those notes. Keep typing to narrow it: #pla matches planning and planning/q4. Select a tag to show only its notes and any nested under it. To find one note among many with a tag, add part of its name after the tag: #planning roadmap.

Open a note to see its tags under Tags in the details panel's Info tab. Select one to search for it.

Agents and tags

An agent connected over MCP calls list_tags to see the tags in use, and list_tags with a tag to find the notes carrying it. get_links on a note includes its tags. Agents add tags the same way people do, by writing them into the note. See the MCP server reference.

Limits

• Private notes stay private. A note that's private to someone else is never listed or counted under a tag for you. See keep files private.
• Markdown only. Tags are read from markdown files. Notes over 2 MB aren't read for tags.
• Older notes. In a workspace with many notes written before tags were indexed, the search says it's still indexing and the list fills in as it works.
• Tags aren't highlighted in the text. An inline #tag reads as ordinary text in the note.