Field Notes — build & deploy handoff

A living portfolio for Justin Young, Director of AI Engineering & Strategy, Southleft. It renders one person's thinking as a 3D gravity system: notes orbit theme masses, unproven ideas fall as particles, old thinking drifts outward and cools, and a black hole at the center holds the memories and the "about."

This is not a "recreate these mockups in React" job. Two of the three pieces are already real, working code. Your job is to finish, wire, and ship them as one deployable thing.

What's in this bundle

site/
  index.html      the map — self-contained HTML + three.js (ES module, importmap CDN)
  engine.html     "the engine behind the map" — plain static page explaining the MCP
  brain.json      the single file of truth; the map renders purely from this
mcp/
  README.md         architecture + guardrails (read first)
  AGENT_BRIEF.md    the original build brief for the server (was CLAUDE.md)
  server.mjs        MCP stdio server + maintenance CLI (decay / chart)
  lib/brain.js      all logic, pure & dependency-free — the guardrails live here
  test/brain.test.mjs  the contract — `npm test`
  nightly.sh        cron entry: decay → chart → git commit/push → site rebuilds
  package.json
  chart-prompt.md / digest-prompt.md / session-digest.md   agent prompts

Run it locally

There is no build step and no dev server to install — the map is a static page that fetches brain.json at runtime. Any static file server works:

cd site && python3 -m http.server 8000    # then open http://localhost:8000

It must be served, not opened as a file:// URL: the fetch('./brain.json') call is subject to CORS and will fail from the filesystem. An internet connection is required too — three.js comes from an SRI-pinned CDN importmap and the fonts from Google Fonts.

Live at https://field-notes.justin-93c.workers.dev — a Cloudflare Worker serving site/ as static assets, deployed from this repo on every push to main. Config lives in wrangler.jsonc; there is no build step.

Fidelity

High-fidelity, and mostly final code.

• site/index.html and site/engine.html are the finished front end — ship them as-is (host them; don't rebuild them in a framework). They use CDN three.js via an importmap and Google Fonts; no build step. If you move to a bundler later, keep the exact visuals, palette, and interactions.
• The mcp/ server is a settled design. Do not redesign it. Finish and wire it per mcp/AGENT_BRIEF.md.

The system in one breath

1. Capture happens inside Claude Code sessions. Mid-work the human says "particle that"; the agent calls brain_propose, appending a particle to brain.json (max 6/day). Agents may only propose — never grant mass.
2. Decay runs nightly from cron: energy ×0.92, suggestions expire after 14 unengaged days, note ages recomputed. Entropy is not a tool; it's not optional.
3. The cartographer (nightly) reads the ledger and may chart ≤2 cited suggestions into deep space.
4. Promotion to a full orbiting note, and memories, happen only by human approval in chat (brain_promote / brain_remember).
5. brain.json is committed & pushed; the static site redeploys and re-renders.

The map is a pure function of brain.json. See engine.html and mcp/README.md for the full data→physics mapping.

Tasks, in order

1. Front end — host the static site. Serve site/ on a static host (Netlify, Vercel, Cloudflare Pages, GitHub Pages). index.html is the entry. Confirm the importmap CDN + fonts load over HTTPS and the map renders. No build step needed.
2. Wire the source links on engine.html. Three links (MCP README, server.mjs, lib/brain.js) currently point to #. Point them at the public repo once it exists (e.g. https://github.com/justiny/<repo>/blob/main/mcp/...).
3. Server — make it real. cd mcp && npm install && npm test on Node 20+. Fix any drift between lib/brain.js and the tests; the tests document intent.
4. Verify the MCP handshake. npx @modelcontextprotocol/inspector node server.mjs with BRAIN_JSON pointed at a copy of brain.json. Exercise all five tools.
5. Register locally. claude mcp add brain -e BRAIN_JSON=$HOME/fieldnotes/brain.json -- node $HOME/fieldnotes/mcp/server.mjs
6. Wire the nightly loop. Make nightly.sh executable; add the cron line from its header; confirm the git commit/push targets the site repo so a push triggers a redeploy.
7. Add the capture protocol. Paste mcp/session-digest.md's block into the user's global ~/.claude/CLAUDE.md so sessions offer to particle-ize claims.
8. Rename mcp/AGENT_BRIEF.md back to CLAUDE.md inside the server repo if you want Claude Code to pick it up automatically (it was renamed only to survive this bundle).

Sharp edges (from the server brief — don't relearn these the hard way)

• saveBrain writes tmp-then-rename on purpose — the site must never read a half-written ledger. Keep it atomic.
• Never change brain.json's existing key shapes; additive fields only. The map computes positions from ageMonths / energy / affinity. If a field looks unused server-side, the map probably uses it — check before pruning.
• Dedupe/accretion similarity is a cheap token overlap, not embeddings, on purpose. If you upgrade it, keep thresholds as named constants and keep lib/brain.js dependency-free.
• The rate limit keys off proposedOn (server date), not the particle's claimed date — a digest back-filling old dates still spends today's six.
• Guardrails live in lib/brain.js, server-side — never in prompts.

Front-end reference (for hosting / minor edits, not a rebuild)

• Palette: bg #121210, ink #E8E4DC, muted #8B8A80 / #5C5B52, bone wireframe #E8E4DC, live green #82C566, redshift/memory orange #E08A3C, hairlines #2A2A26 / #3A3A34.
• Type: Space Grotesk (display/body), IBM Plex Mono (labels/UI), mono at 9–10px with .14–.2em letter-spacing.
• Deps: three.js 0.184.0 via importmap + OrbitControls (CDN, SRI-pinned in the <head>); Google Fonts. Nothing else.
• Interactions: drag-orbit / scroll-zoom / click-a-note-to-dive-and-read / double-click-home; top-right MENU (links + About dive + timeline rewind + reset view); bottom time-scrubber unwinds the year; bottom-right minimap is a travel pad (click to glide, drag to fly). The black-hole interior holds memories, a rotating tesseract singularity (the "about"), and redshift on the way in.