Brain Search: look in the brain before you ask

The rule: retrieval first

A fact about the user's life or work (a decision, a price, a person, a date, how something was done) is searched before it is asked. The order:

1. brain_search.py (this skill).
2. The project Door, if the question is about a project (project-door).
3. A plain text search of the vault, for an exact number or phrase.
4. Only then, ask the user. If they answer with a durable fact, offer to save it.

Asking the user something their own brain already knows wastes their time and teaches them the brain is not worth feeding.

How it works

The kit keeps a search index of the whole vault at {{VAULT_PATH}}/.brain/brain.sqlite (SQLite FTS5, built with only the Python standard library). It ranks by relevance (bm25): a word in the title, description, aliases or tags weighs more than the same word in the body. Accents do not matter.

T="{{VAULT_PATH}}/.brain/tools"
python3 "$T/brain_search.py" "raised beds"                       # every word must appear
python3 "$T/brain_search.py" "\"raised beds\""                   # exact phrase
python3 "$T/brain_search.py" compost --prefix                    # compost* (composting, composts)
python3 "$T/brain_search.py" budget --type decision --sort date  # newest decision first
python3 "$T/brain_search.py" garden --folder "06 Session Logs" --since 2026-09-01
python3 "$T/brain_search.py" "pricing" --project kitchen --limit 5
python3 "$T/brain_search.py" roof --json                         # for further processing

If nothing has every word, it retries with any of them and says so.

Recipes

Filters

--type, --project, --folder, --status, --not-folder, --title, --tag, --since, --until, --limit, --sort rank|date, --prefix, --raw (FTS5 syntax as is, e.g. title:budget, NEAR(a b)). Filters are case-insensitive substring matches and accept a comma list.

Keeping the index fresh

The index is rebuilt in seconds, whole, every time:

python3 "{{VAULT_PATH}}/.brain/tools/brain_index.py"

It runs at the end of save-to-obsidian and close-session, and every month with the health check. If a search says the index is more than 24 hours old, rebuild it first.

Without Python

If python3 is not available (or the index cannot be built), fall back to a plain text search of the vault with the host's file search (Grep/Glob, or grep -ril "word"), starting with file names and the description: lines, then the bodies. Same order, less ranking.

How to answer

• Answer from what the notes say, and name the note each fact came from as a [[link]], so the user can open it.
• Read the top 1 to 3 notes before answering; the snippet is a pointer, not the answer.
• If two notes disagree, say so and show both, newest first. Do not pick one silently.
• If nothing is found, say it plainly ("nothing in the brain about X"), then ask.
• Show the work in one line: "Searched the brain for X: 3 notes, used the first two."

Changelog

• 2.0.0 (2026-10-02): New skill. Local FTS5 index, retrieval-first rule, recipes.