brain_remember

The write side. Takes a category + title + body, attaches #claude-brain, returns the new note’s id + canonical path.

Parameters

Name	Type	Required	Description
`category`	enum	yes	One of `standards`, `decisions`, `lessons`, `apps`, `reviews`, `drafts`
`title`	string	yes	Concise note title
`body`	string	yes	Note body (≥20 chars)
`app`	string	when `category=apps`	App name — note lands under `Apps/<app>/`
`tags`	string[]	no	Extra tags beyond `#claude-brain`

Enforcement

For category=decisions or category=lessons, the body must contain What:, Why:, and Evidence: lines. Without all three, the call is refused:

Error: decisions notes require all three of "What:", "Why:", "Evidence:" in the body.
If you can't fill all three, this is an opinion, not a decision/lesson — write it as a draft instead.

This is intentional. Decisions without evidence aren’t decisions, they’re opinions. Opinions go in drafts, not decisions.

Example

brain_remember(
  category="lessons",
  title="2026-03-12 — Idempotent migrations broke under retry",
  body=`
    What:     A schema migration ran twice in a single deploy and corrupted a
              counter column.
    Why:      The CI step retried on a transient lock timeout, but the migration
              wasn't idempotent — the UPDATE statement assumed prior state.
    Evidence: deploy log shows two consecutive runs of migration 0042; counter
              row went from 100 to 200 to 300 in three seconds. PR #482 added
              the idempotency guard.
  `
)

→ Wrote (backend=trilium): Claude Memory/Lessons Learned/2026-03-12 — Idempotent migrations broke under retry
    id: R7qg6gS70u6S
    tags: claude-brain

When to call it (auto-trigger heuristics)

The discipline skill defines when Claude should write proactively:

Event	Category
User corrects with a non-obvious reason	`standards`
Bug fix with non-obvious root cause	`lessons`
Design choice between viable alternatives	`decisions`
App-specific gotcha	`apps`
Independent reviewer finding	`reviews`

If unsure, Claude asks first. Better to skip a note than fill the brain with noise.