🧠 Brain of Reese
A chippy, honest RAG chatbot over the ~/Homelab and ~/Deployments
projects. Point it at your notes — markdown, YAML, JSON, Python, plain
text — ask it anything, and it retrieves the relevant chunks with
hybrid search (pgvector cosine ∪ Postgres full-text search, fused with
Reciprocal Rank Fusion), feeds the whole relevant document to a
self-hosted LLM (turbo via https://aipi.reeseapps.com/v1), and
streams a grounded answer back.
If it doesn't have notes for your question, it admits it: "I haven't done anything like that" — plus suggestions for what it does know.
Updated your notes? The knowledge base is refreshed by re-running the import — it's idempotent and only re-embeds what changed:
uv run python -m scripts.import_docs --pruneDetails in Updating the documents.
- Stack: FastAPI · Pydantic v2 · SQLAlchemy 2 · Alembic · pgvector · vanilla HTML/CSS/JS (no CDN) · Playwright E2E
- Planning: architecture, LOCKED decisions and the phase roadmap live
in
.agent/PLAN.md; per-story specs in.agent/user_stories/.
Development Setup
Prerequisites
- uv
- Podman (with the
podman composeprovider) - Node.js is not needed locally (asset minification happens in the container build only)
1. Install dependencies
uv sync
2. Configure
cp .env.example .env
# edit .env — the defaults already match the local compose setup.
# BOR_LLM_API_KEY: your aipi key (falls back to $AIPI_KEY if unset)
3. Start the database (Postgres 17 + pgvector)
podman compose up -d db
podman compose ps # wait until "healthy"
4. Apply migrations
uv run alembic upgrade head
5. Import your knowledge base
uv run python -m scripts.llm_probe # sanity: models + 768-dim check
uv run python -m scripts.import_docs # defaults: ~/Homelab + ~/Deployments
6. Run the app
uv run uvicorn app.main:app --reload
# → http://localhost:8000 (chat) http://localhost:8000/sources.html (KB)
📝 After this, day-to-day is just: edit markdown → re-run the import. See Updating the documents below.
Using the UI
- Chat (
/) — ask questions; answers stream in with source chips that cite the exact documents used. Clicking a chip opens that document in a new tab. - Document viewer (
/document.html?source=…&path=…) — the full text of any indexed document, served from the database (no filesystem access): markdown is rendered, every other format (yaml,json,py,txt, …) is shown as escaped monospace text. Unknown documents get a designed not-found state with a link back to the index. - Sources (
/sources.html) — the indexed document list; the Path column links each document to the viewer in a new tab. Admin-only — anonymous visitors see a sign-in gate instead (the catalog is what the login locks; the document viewer itself stays open to everyone).
Admin & sign-in
Brain of Reese has exactly one account: the admin (you). Signing in unlocks the full Sources catalog and the answer-tuning controls; everyone else stays anonymous and keeps chat and the document viewer (any document an answer cites can be opened by its direct URL — the catalog is gated, not the viewer).
Setup (one-time)
python -c 'import secrets;print(secrets.token_hex(32))' # → paste into .env
BOR_ADMIN_PASSWORD=your-password # plaintext — homelab scope, by design
BOR_SESSION_SECRET=<the hex from above> # signs the session cookie
Fail-loud: while either variable is empty the app refuses to start, naming the missing one(s):
RuntimeError: Brain of Reese cannot start: admin auth is not configured.
Set the missing variable(s): BOR_ADMIN_PASSWORD, BOR_SESSION_SECRET …
How it works
POST /api/login {"password": …}→204+ signedbor_sessioncookie (StarletteSessionMiddleware— an itsdangerous-signed cookie, no server-side store, no new service, no DB table); any mismatch →401{"detail": "invalid password"}(constant-time compare, one generic message — no user enumeration, there is only one user).POST /api/logout→204(session cleared and cookie expired; idempotent for anonymous callers).GET /api/whoami→{"authenticated": bool, "role": "admin"|"anonymous"}— the single source of truth for every UI gating decision.- Cookie flags:
same_site="lax",https_onlyoff — no HTTPS enforcement on purpose (homelab HTTP; the cookie is single-admin convenience, not a cloud boundary). Max ageBOR_SESSION_MAX_AGE(default43200= 12 h, refreshed while active). - Sign in from the chat header (Sign in) or
/login.htmldirectly; the header then offers Sign out (logout + reload).
Who can do what
| Capability | Anonymous | Admin (signed in) |
|---|---|---|
Chat (/) + suggestion chips |
yes | yes |
Document viewer (/document.html?source=…&path=…) |
yes — any indexed doc by direct URL | yes |
Sources catalog (/sources.html, GET /api/docs) |
sign-in gate | full catalog |
Tuning (Tune button, Tuning panel, /api/steering) |
UI hidden | full |
The public API endpoints stay stateless — the signed cookie is the only session state in the system.
Tuning your answers
Admin-only — sign in first (see Admin & sign-in above); anonymous visitors never see the Tune button or the Tuning panel.
If an answer isn't quite right — too chatty, wrong assumption, missing context — tune Brain right there:
- Press “Tune” in the meta row under any completed answer (deflected ones included).
- Type a short instruction (1–2000 chars), e.g. “be more concise” or “assume I'm on NixOS”, and Save.
The note is stored in Postgres (steering_notes) and read into the
system prompt of every subsequent chat turn as a <tuning> section
(numbered, oldest first, capped at BOR_STEERING_MAX_CHARS chars —
default 8000, overflow marked […truncated…]). With no stored notes the
prompt is byte-identical to the un-tuned one, so tuning is opt-in per
note.
List or remove notes at any time from the “Tuning” button in the chat header (count badge, newest-first, per-note delete). The API is stateless JSON if you prefer curl:
curl -s localhost:8000/api/steering # list (newest first)
curl -s -X POST localhost:8000/api/steering \
-H 'Content-Type: application/json' -d '{"note": "be more concise"}'
curl -s -X DELETE localhost:8000/api/steering/<note-id> # remove
Updating the documents
This is the workflow you'll use most. The knowledge base is refreshed by re-running the import. It is idempotent and delta-based (sha256 per file), so a refresh after a normal editing session takes seconds:
# After editing/adding/removing notes in your projects:
uv run python -m scripts.import_docs # re-index what changed
uv run python -m scripts.import_docs --prune # also drop deleted/out-of-scope files
# Point it at extra directories (repeatable):
uv run python -m scripts.import_docs --source ~/SomeOtherDocs
Then check the Sources page (http://localhost:8000/sources.html):
the documents / chunks counters and last indexed timestamp should
reflect the new files, and each document row shows when it was last
embedded.
- The import prints one line per file (
import: added|updated|unchanged| pruned …) and ends with a greppable summary (import: summary files=… added=… updated=… unchanged=… pruned=… chunks=… embed_batches=… formats=md:203,yaml:267,…), so it is safe to run from a cron job or after every commit. - Indexed formats (A9):
md, markdown, txt, yaml, yml, json, py(case-insensitive; narrow withBOR_IMPORT_EXTENSIONS). Any path with a dot-prefixed component — hidden files or vendored caches like.esphome/.espressif/**— is skipped, along with.venv,node_modules,.git,__pycache__,.pytest_cache,dist,build.--prunealso drops documents whose files no longer match the filter — that's how previously imported junk leaves the index. - Non-markdown files get format-aware chunking (YAML top-level keys /
---docs, JSON top-level keys, Python top-level defs/classes via stdlibast) and their title comes from the file stem. - Unchanged files are not re-embedded — only new/changed ones, so refreshes are cheap.
- To sanity-check the LLM backend (models + embedding dimension) after any
aipi change:
uv run python -m scripts.llm_probe.
Checking retrieval quality
Ask the real pipeline (live aipi embeddings + the current KB) whether a question lands on the right document, with the gate verdict and per-document cosine / FTS / fused scores:
uv run python -m scripts.eval_retrieval "How did I install gitlab?"
uv run python -m scripts.eval_retrieval --from-file questions.txt --top 8
Requires AIPI_KEY in the environment (same convention as
scripts/llm_probe.py) and an imported knowledge base.
How retrieval works (hybrid)
Every question is embedded and also lexically tokenized (OR-joined, English stemming) and searched twice against Postgres:
- Vector — pgvector cosine top-N (default
BOR_HYBRID_VECTOR_CANDIDATES=100) - Lexical — a stored
tsvector(GIN-indexed) matched withto_tsquery, top-N byts_rank(defaultBOR_HYBRID_LEXICAL_CANDIDATES=30)
The two ranked lists are fused with Reciprocal Rank Fusion
(score = Σ 1/(k + rank), BOR_RRF_K=60) — a chunk in both lists scores
nearly double, which is what lets a name-your-tool question ("gitlab") find
its own document even when the question embeds close to generic templates.
The honesty gate (A8) then answers (HIGH) when the best cosine is ≥
BOR_RELEVANCE_THRESHOLD (default 0.62) or at least one chunk matched
lexically (fts_hits > 0) — it deflects (LOW) only when both signals are
absent. The top BOR_TOP_N_DOCS full documents are still what the LLM sees.
query_log records every turn (top_score = best cosine, fts_hits,
chunk_hits, deflected, sources, latency_ms) — the raw material for
tuning: psql … -c 'SELECT question, top_score, fts_hits, deflected FROM query_log ORDER BY created_at DESC LIMIT 20'.
Debugging
debugpy is off by default and never imported unless you opt in —
zero overhead in normal runs.
DEBUGPY=1 uv run uvicorn app.main:app
# → log line: debugpy: remote debugging ENABLED, listening on 0.0.0.0:5678
Then attach from VS Code (.vscode/launch.json):
{
"name": "Attach to Brain of Reese",
"type": "debugpy",
"request": "attach",
"connect": { "host": "localhost", "port": 5678 },
"pathMappings": [
{ "localRoot": "${workspaceFolder}", "remoteRoot": "/app" }
]
}
The port is non-blocking and attach-on-demand: the app keeps running
normally until you attach. Override the port with DEBUGPY_PORT.
QA / Testing Environment
Three layers — the project rule is one story, one phase, one Playwright
suite (see AGENTS.md):
# Unit + integration (FastAPI TestClient)
uv run pytest
# Same, with the coverage gate (phases require >90% on app/)
uv run pytest --cov=app --cov-report=term-missing
# Lint + static types
uv run ruff check .
uv run pyright
# Playwright E2E — install the browser once:
uv run playwright install chromium
# Each story's E2E runs IN ISOLATION (DB must be up):
podman compose up -d db
uv run pytest tests/e2e/test_import_documents.py -v --no-cov
uv run pytest tests/e2e/test_chat_rag.py -v --no-cov
# ...one file per story in .agent/user_stories/ (see .agent/phases/todo/)
Deterministic E2E: by default the E2E app talks to a local mock
aipi (tests/e2e/mock_llm.py) whose embeddings are real
token-overlap vectors — so the cosine relevance threshold behaves like
production (on-topic questions answer, off-topic ones deflect).
To run E2E against the live self-hosted models instead:
E2E_REAL_LLM=1 uv run pytest tests/e2e/test_chat_rag.py -v --no-cov
(requires a real import of your docs first).
Production Deployment
Build the multi-stage image (frontend minified by esbuild in the builder
stage, deps installed by uv, non-root runtime):
podman build -t brain-of-reese/app:latest .
Run standalone (bring your own Postgres + pgvector):
podman run -d --name brain-of-reese \
-p 8000:8000 \
-e BOR_DATABASE_URL=postgresql+psycopg://reese:SECRETPASSWORD@dbhost:5432/brain_of_reese \
-e BOR_LLM_BASE_URL=https://aipi.reeseapps.com/v1 \
-e BOR_LLM_API_KEY=$AIPI_KEY \
brain-of-reese/app:latest
The entrypoint runs alembic upgrade head automatically on start.
Or run the whole stack from compose (app + db):
podman compose --profile prod up -d --build
Production hardening notes: app runs as non-root (uid 10001), slim image,
healthcheck on /api/health, debugpy off unless DEBUGPY=1, all assets
served locally (no CDN), BOR_ENVIRONMENT=production.
Configuration reference
| Env | Default | Meaning |
|---|---|---|
BOR_DATABASE_URL |
local compose URL | SQLAlchemy URL (psycopg) |
BOR_LLM_BASE_URL |
https://aipi.reeseapps.com/v1 |
OpenAI-compatible endpoint |
BOR_LLM_API_KEY |
— (falls back to $AIPI_KEY) |
aipi API key |
BOR_LLM_CHAT_MODEL |
turbo |
chat model |
BOR_LLM_EMBED_MODEL |
embed |
embedding model |
BOR_EMBEDDING_DIM |
768 |
vector dimension (fixed at table creation) |
BOR_TOP_N_DOCS |
2 |
full documents fed to the LLM |
BOR_RELEVANCE_THRESHOLD |
0.62 |
answer when best cosine ≥ this or an FTS hit; below + no FTS ⇒ honest deflection |
BOR_HYBRID_VECTOR_CANDIDATES |
100 |
cosine list width for the RRF fusion |
BOR_HYBRID_LEXICAL_CANDIDATES |
30 |
FTS list width for the RRF fusion |
BOR_RRF_K |
60 |
RRF damping constant (1/(k + rank)) |
BOR_IMPORT_EXTENSIONS |
md,markdown,txt,yaml,yml,json,py |
csv of importable formats (may only narrow the A9 set) |
BOR_MAX_CONTEXT_CHARS |
24000 |
cap on total document text sent to the LLM |
BOR_STEERING_MAX_CHARS |
8000 |
char budget for the <tuning> (steering notes) prompt section |
BOR_SUGGESTIONS |
built-in list | JSON list of onboarding chips |
BOR_ADMIN_PASSWORD |
(required) | the single admin's password (plaintext, .env); app refuses to start when empty |
BOR_SESSION_SECRET |
(required) | signing key for the bor_session cookie; python -c 'import secrets;print(secrets.token_hex(32))' |
BOR_SESSION_MAX_AGE |
43200 |
session-cookie lifetime in seconds (12 h, sliding) |
DEBUGPY |
0 |
1 ⇒ attach-on-demand debugpy on DEBUGPY_PORT (default 5678) |
BOR_LOG_LEVEL |
INFO |
app log level |
Troubleshooting
401from aipi — setBOR_LLM_API_KEY(or$AIPI_KEY).litellm.UnsupportedParamsError … encoding_formatfrom aipi — the aipi proxy (litellmopenai_like) rejects theencoding_formatparameter that theopenaiSDK injects into every embeddings request. The app already works around this by POSTing a minimal{model, input}payload through the openai client's own httpx transport (app/rag/llm.py→LLMClient._embed_batch). If you see this, you are likely calling the endpoint with a different client — drop the parameter (or setlitellm.drop_params = Trueon the proxy).- Embedding dimension mismatch — aipi changed models; run
uv run python -m scripts.llm_probe, updateBOR_EMBEDDING_DIM, then drop + recreate the chunks table (new migration or manualTRUNCATE chunks, documents). - Honest deflection (the amber “I haven't done anything like that”
bubble) — every question passes the honesty gate: deflection happens
only when the best cosine similarity is below
BOR_RELEVANCE_THRESHOLD(default0.62) and no chunk matched the question lexically (fts_hits = 0). A weak cosine with a lexical hit (name-your-tool questions) still gets a grounded answer. When it does deflect, the LLM prompt carries weak-hit titles only (no document content), the reply opens with “I haven't done anything like that”, the bubble renders amber with “Maybe try” chips derived from the closest indexed titles, the SSEdoneevent carriesdeflected: true+suggestions[], and thequery_logrow recordsdeflected=true+ the weaktop_score+fts_hits. This is a feature, not a bug — the KB simply has no notes that close; the chips always point at topics Brain really covers. - Answers deflect too often / too rarely — tune
BOR_RELEVANCE_THRESHOLD(lower = answers more, higher = more honest deflection):0.0⇒ the gate leans entirely on FTS hits;1.0⇒ everything deflects unless a chunk matches lexically. Theembedmodel's cosines cluster in a ~0.6–0.85 band on the live KB, so the default is0.62; after changing it, check the real scores:psql … -c 'SELECT question, top_score, fts_hits, deflected FROM query_log ORDER BY created_at DESC LIMIT 20' - KB offline banner in the chat — Postgres isn't running:
podman compose up -d db. - Stuck "Thinking…" — the LLM is slow or down; a 120s client timeout turns it into an error banner automatically.