Tags & entities

Tags and entities are the two ways Aletheia makes your notes findable by what they're about rather than just what they say. Both are largely automatic.

A note's tags render as clickable chips in its header. **①** project.orion · **②** a tag · **③** client.acme.

Tags

A tag is a hashtag — #decision, #project/orion, #client/acme. Tags are hierarchical: the / builds a path, so #project/orion is a child of #project, and filtering by #project catches everything beneath it.

Tags arrive two ways:

• Auto-tags — extraction infers topical hashtags from the note's text and attaches them.
• Your tags — add them in prose (#like-this) or via + Add tag in the sidecar.

Type a hashtag in prose and it renders as an inline #tag chip (highlighted) right where you wrote it.

The + Add tag control (highlighted) gives you a type-ahead to attach an existing or new tag.

Click any tag chip — in a note, the sidecar, or a search result — to run a search filtered to that tag (and, because tags are hierarchical, its children).

Design a small tag vocabulary and reuse it

Tags are most useful when they're consistent. A compact scheme — #decision, #risk, #meeting, #project/<name>, #client/<name> — beats a sprawl of one-off tags. Because they nest, #project/orion and #project/atlas both roll up under #project for free.

Entities

An entity is a person, organization, project, location, or date your notes mention. Aletheia extracts these automatically and — crucially — recognizes the same entity across every note that names it. Mention "Mara Castellan" in ten notes and there's one Mara, linked to all ten.

Entities render as chips wherever they appear:

• In the note body (in Rich view), inline where you named them.
• In the sidecar's Entities section, with a per-note mention count.
• In search results and chat answers.

Named people render inline as entity chips. **①** Mara Castellan · **②** Julian Rao · **③** Priya Desai.

The same entities are collected in the sidecar's Entities section. **①** Entities heading · **②** an individual entity chip.

Clicking an entity chip opens that entity — the thread you pull to answer "everything about Acme Robotics" or "what has Priya been involved in".

Clicking an entity chip — here the "Acme Robotics" chip (highlighted) — opens that entity's page.

Entities need names

Extraction keys on named references. "The vendor said…" won't link; "Acme said…" will. When a person or org matters for later recall, name them explicitly at least once in the note.

Tags vs. entities — which is which?

	Tag	Entity
Answers	What topic?	Who / what thing?
Looks like	#decision, #project/orion	Mara Castellan, Acme Robotics
Shape	Hierarchical path	A named person/org/project/place/date
You control	Add your own freely	Extracted from names in text

Use tags for the kind of note (a decision, a risk, a meeting) and entities — which you mostly just get for free — for the people and things it involves.

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