Brain

Persistent memory across sessions. Obsidian vault at brain/.

The brain is the foundation of the entire workflow — every agent, skill, and session reads it. Low-quality or speculative content degrades everything downstream. Before adding anything, ask: "Does this genuinely improve how the system operates?" If the answer isn't a clear yes, don't write it.

Before Writing

Read brain/index.md first. Then read the relevant entrypoint for your topic:

brain/principles.md for principle updates

For directories without a dedicated index file yet, scan nearby files directly and edit an existing note when possible.

Structure

brain/
├── index.md              <- root entry point, links to everything
├── principles.md         <- index for principles/
├── principles/           <- engineering and design principles
├── codebase/             <- project-specific knowledge and gotchas
└── plans/                <- feature plans

Rules:

One topic per file. brain/codebase/deploy-gotchas.md, not a mega-file.
Maintain existing index entrypoints: brain/index.md, brain/principles.md.
If you introduce a new top-level category, add an index-style entrypoint for it (links only, no inlined content).
brain/index.md is the root. Every brain file must be reachable from it.
File names: lowercase, hyphenated. worktree-gotchas.md.

Wikilinks

Format: [[section/file-name]]. Resolution order: same directory, then relative path, then vault root. Heading anchors ([[file#heading]]) are stripped during resolution.

Writing Style

Bullets over prose. No preamble.
Plain markdown with # Title. No Obsidian frontmatter.
Keep notes under ~50 lines. Split if longer.

After Writing

Update brain/index.md for any files you added or removed. Also update the relevant entrypoint when applicable. Keep indexes link-only and scannable.

Durability Test

Ask: "Would I include this in a prompt for a different task?"

Yes -> write to brain/. It's durable knowledge.
No, it's plan-specific -> update the plan's docs instead.
No, it's a skill issue -> update the skill file directly.
No, it needs follow-up work -> file a todo.

Maintenance

Delete outdated or subsumed notes.
Merge overlapping notes before adding new ones.