app.py

#!/usr/bin/env python
"""RAG Q&A with Citations — ask a question, get an answer grounded ONLY in a curated
construction & remodeling knowledge base, with inline [n] citations to the exact sources —
and an honest "I couldn't find that in the knowledge base" when the answer isn't there.

Real RAG: chunk -> embed (fastembed, ONNX/CPU, no torch) -> retrieve (cosine) -> Claude answers
from the retrieved sources only, citing each. No hallucinating past the sources.

  pip install flask requests anthropic fastembed numpy
  python app.py            # http://127.0.0.1:7860

Project #10 of the "30 Projects in 15 Days" challenge — GritAI.
"""
import os, re, json
import numpy as np
from flask import Flask, request, jsonify, Response

PORT = int(os.environ.get("PORT", "7860"))
ANTHROPIC_KEY = (os.environ.get("ANTHROPIC_API_KEY") or "").strip() or None
ANTHROPIC_MODEL = os.environ.get("ANTHROPIC_MODEL", "claude-haiku-4-5")
TOP_K = 4

# ============================ Construction & Remodeling KB ============================
# General, public industry knowledge (no proprietary data). Each entry is a citable source.
KB = [
 {"t": "Do I need a building permit?",
  "x": "Most structural, electrical, plumbing, and mechanical work requires a permit from your local "
       "building department — including additions, removing or moving walls, new circuits, water-heater "
       "replacement, decks over a certain height, and re-roofing in many areas. Cosmetic work (paint, "
       "flooring, cabinets, fixtures that reuse existing connections) usually does not. Permits exist to "
       "ensure work meets code and passes inspection; unpermitted work can cause problems when you sell. "
       "When unsure, call your local building department and ask — it's free."},
 {"t": "How permits and inspections work",
  "x": "You (or your licensed contractor) submit plans and pay a fee; the department issues the permit; "
       "work is done in phases with inspections at key points — typically a rough-in inspection (framing, "
       "electrical, plumbing before walls are closed) and a final inspection when complete. Don't cover "
       "walls until the rough-in passes. Keep the permit posted on site. Final sign-off closes the permit."},
 {"t": "Hiring a contractor: licenses and insurance",
  "x": "Verify the contractor holds a current state license for the trade and carries liability insurance "
       "and workers' compensation. Ask for the license number and confirm it with your state licensing "
       "board. Uninsured workers injured on your property can become your liability. For larger jobs, a "
       "general contractor coordinates subcontractors and pulls permits."},
 {"t": "Getting and comparing bids",
  "x": "Get at least three written bids for the same defined scope so they're comparable. A good bid itemizes "
       "labor, materials, permits, timeline, and payment schedule. Be wary of a bid far below the others — it "
       "often means missing scope or corners cut. Don't automatically pick the lowest; weigh reputation, "
       "references, and clarity."},
 {"t": "Contracts, deposits, and payment schedules",
  "x": "Always use a written contract listing scope, materials, price, start/finish dates, and a payment "
       "schedule tied to milestones. A common structure is a modest deposit, progress payments as phases "
       "complete, and a final payment after the work passes inspection and you're satisfied. Avoid paying "
       "large sums up front; never pay in full before work is done."},
 {"t": "Mechanic's liens and lien waivers",
  "x": "If a contractor or supplier isn't paid, they can file a mechanic's lien against your property even if "
       "you paid your general contractor. Protect yourself by requesting lien waivers from subcontractors and "
       "suppliers as they're paid, confirming the money reached them."},
 {"t": "Budgeting and the contingency fund",
  "x": "Set aside a contingency of 10–20% of the project budget for surprises — older homes especially hide "
       "problems (outdated wiring, water damage, non-code framing) behind the walls. Renovations frequently "
       "run over when hidden conditions surface; the contingency keeps a surprise from stalling the job."},
 {"t": "Kitchen remodel: scope, cost drivers, and timeline",
  "x": "Kitchens are among the most expensive rooms to remodel because they combine cabinetry, countertops, "
       "appliances, plumbing, electrical, and often flooring. Cabinetry and countertops are usually the "
       "biggest line items. Moving plumbing or gas lines and relocating walls adds significant cost. A typical "
       "mid-range kitchen remodel runs several weeks to a couple of months depending on scope and lead times "
       "on custom cabinets."},
 {"t": "Bathroom remodel basics",
  "x": "Bathrooms pack plumbing, waterproofing, tile, ventilation, and electrical into a small space, so labor "
       "per square foot is high. Proper waterproofing behind tile in showers is critical to prevent hidden "
       "rot and mold. A quality exhaust fan vented outside (not into the attic) prevents moisture damage. "
       "Moving the toilet, tub, or shower drain locations raises cost because it means opening the floor."},
 {"t": "Flooring options compared",
  "x": "Common choices: hardwood (durable, refinishable, higher cost, sensitive to moisture); engineered wood "
       "(more moisture-stable, thinner wear layer); luxury vinyl plank/LVP (waterproof, budget-friendly, great "
       "for kitchens/baths/basements); tile (very durable and waterproof, harder and colder underfoot); and "
       "carpet (soft and cheap, wears faster). Match the material to the room's moisture and traffic."},
 {"t": "Interior painting: prep and product",
  "x": "A lasting paint job is 80% prep: clean surfaces, fill and sand holes, caulk gaps, and prime bare or "
       "patched areas and stains. Use the right sheen — flat/matte hides wall flaws, eggshell/satin is a good "
       "durable middle for most walls, and semi-gloss resists moisture on trim, kitchens, and baths. One "
       "gallon covers roughly 350–400 square feet per coat; most jobs need two coats."},
 {"t": "Drywall: hanging, taping, and patching",
  "x": "Standard wall drywall is ½ inch; ceilings often use 5/8 inch to resist sagging. Screw to the studs, "
       "then tape and apply three coats of joint compound, sanding between coats for a smooth, feathered seam. "
       "Small holes are patched with mesh or a patch kit and compound; large holes need a backed drywall "
       "patch. Use moisture-resistant board in wet areas."},
 {"t": "Framing and load-bearing walls",
  "x": "Walls are framed with studs spaced 16 inches on-center (sometimes 24). A load-bearing wall carries "
       "weight from above (roof, upper floors) down to the foundation; removing or altering one requires a "
       "properly sized beam and usually an engineer and a permit. Never remove a wall without confirming "
       "whether it's load-bearing — getting this wrong is dangerous."},
 {"t": "Roofing: materials and when to replace",
  "x": "Asphalt shingles are the most common and last roughly 15–30 years depending on quality; metal roofs "
       "last longer at a higher cost. Signs you need a new roof include curling or missing shingles, granules "
       "collecting in gutters, daylight or leaks in the attic, and sagging. Re-roofing usually needs a permit "
       "and an inspection."},
 {"t": "Insulation and energy efficiency (R-value)",
  "x": "Insulation is rated by R-value — higher means more resistance to heat flow. Attics benefit most from "
       "added insulation and are usually the cheapest place to improve efficiency. Air-sealing gaps and leaks "
       "before insulating matters as much as the insulation itself. Common types include fiberglass batts, "
       "blown-in cellulose, and spray foam (higher cost, also air-seals)."},
 {"t": "Electrical basics and when to call a pro",
  "x": "Simple like-for-like swaps (a switch or outlet) are often DIY, but new circuits, panel work, and "
       "anything you're unsure about should go to a licensed electrician and be permitted. Kitchens, baths, "
       "garages, and outdoors require GFCI protection; many circuits now require AFCI breakers. Never work on "
       "a live circuit — shut off the breaker and verify it's dead."},
 {"t": "Plumbing basics and rough-in",
  "x": "Plumbing is installed in two stages: the rough-in (supply and drain lines inside the walls and floor, "
       "inspected before closing up) and the finish (fixtures and trim). Proper drain slope (about ¼ inch per "
       "foot) and venting are required for drains to flow and to keep sewer gas out. Relocating fixtures means "
       "opening walls or floors, which drives cost."},
 {"t": "Decks: footings, materials, and permits",
  "x": "Decks generally need a permit and rest on footings dug below the local frost line so they don't heave. "
       "Materials range from pressure-treated lumber (cheapest) to cedar to composite (low-maintenance, higher "
       "cost). Proper flashing where the deck ledger meets the house prevents rot and is a common failure "
       "point. Railings and stair dimensions are code-regulated for safety."},
 {"t": "Concrete and foundation cracks",
  "x": "Thin, hairline cracks in concrete are common from normal curing and shrinkage and are usually cosmetic. "
       "Warning signs that need a professional include cracks wider than about ¼ inch, horizontal cracks in "
       "foundation walls, cracks that are growing, or doors and windows that suddenly stick — these can signal "
       "settlement or structural movement."},
 {"t": "HVAC sizing and maintenance",
  "x": "Heating and cooling equipment must be correctly sized for the home — an oversized system short-cycles "
       "and controls humidity poorly, while undersized struggles to keep up. Sizing is done with a load "
       "calculation (Manual J), not a rule of thumb. Basic maintenance — changing filters regularly and an "
       "annual service — extends equipment life and efficiency."},
 {"t": "Older homes: lead paint and asbestos",
  "x": "Homes built before 1978 may contain lead-based paint, and homes from roughly the 1980s and earlier may "
       "contain asbestos in flooring, popcorn ceilings, insulation, and duct wrap. Disturbing these during a "
       "remodel releases hazardous dust. Testing before demolition and using certified abatement pros for "
       "removal is the safe, and often legally required, path."},
 {"t": "Project phases and realistic timelines",
  "x": "A typical renovation flows through phases: design and permitting, demolition, rough-in (framing, "
       "electrical, plumbing, HVAC) with inspections, insulation and drywall, then finishes (paint, flooring, "
       "cabinets, trim, fixtures) and a final inspection. Material lead times — especially custom cabinets, "
       "windows, and specialty tile — often drive the schedule more than the labor does."},
 {"t": "Return on investment of common projects",
  "x": "Not all projects return equal value at resale. Curb-appeal and maintenance items (a new front door, "
       "garage door, fresh paint, and minor kitchen and bath updates) tend to recoup a larger share of their "
       "cost than high-end additions. Over-improving beyond the neighborhood's price range rarely pays back "
       "the full investment."},
]

# ============================ embeddings + retrieval ============================
_EMB = None
_MAT = None  # normalized KB embedding matrix


def emb_model():
    global _EMB
    if _EMB is None:
        from fastembed import TextEmbedding
        _EMB = TextEmbedding("BAAI/bge-small-en-v1.5")
    return _EMB


def _norm(m):
    n = np.linalg.norm(m, axis=-1, keepdims=True)
    return m / np.clip(n, 1e-8, None)


def build_index():
    global _MAT
    texts = [f"{d['t']}. {d['x']}" for d in KB]
    vecs = np.array(list(emb_model().passage_embed(texts)), dtype=np.float32)
    _MAT = _norm(vecs)


if os.environ.get("SPACE_ID"):     # warm the index at startup on the Space
    try:
        build_index()
        print("[startup] KB index built", flush=True)
    except Exception as _e:
        print(f"[startup] index build failed (will retry on first ask): {_e}", flush=True)


def retrieve(question, k=TOP_K):
    if _MAT is None:
        build_index()
    q = _norm(np.array(list(emb_model().query_embed([question]))[0], dtype=np.float32).reshape(1, -1))[0]
    sims = _MAT @ q
    idx = np.argsort(-sims)[:k]
    return [(int(i), float(sims[i])) for i in idx]


TOOL = {
    "name": "answer",
    "description": "Answer the question using ONLY the provided sources.",
    "input_schema": {"type": "object", "properties": {
        "found": {"type": "boolean", "description": "true only if the sources actually answer the question."},
        "answer": {"type": "string", "description": "The answer, grounded in the sources, with inline citations "
                   "like [1] or [2] pointing to the source numbers used. If found is false, briefly say the "
                   "knowledge base doesn't cover it."},
        "used": {"type": "array", "items": {"type": "integer"}, "description": "Source numbers actually cited."}},
        "required": ["found", "answer", "used"]},
}


def answer_question(question):
    hits = retrieve(question)
    sources = [{"n": i + 1, "title": KB[idx]["t"], "text": KB[idx]["x"], "score": round(sc, 3)}
               for i, (idx, sc) in enumerate(hits)]
    if not ANTHROPIC_KEY:
        return {"found": False, "answer": "Set ANTHROPIC_API_KEY on the server to generate answers.",
                "used": [], "sources": sources}
    block = "\n\n".join(f"[{s['n']}] {s['title']}\n{s['text']}" for s in sources)
    sysp = ("You answer questions about construction and home remodeling using ONLY the numbered SOURCES "
            "provided. Ground every claim in the sources and cite them inline as [n]. If the sources do not "
            "actually contain the answer, set found=false and say the knowledge base doesn't cover it — never "
            "guess or use outside knowledge. Be concise and practical.")
    try:
        import requests
        resp = requests.post("https://api.anthropic.com/v1/messages",
            headers={"x-api-key": ANTHROPIC_KEY, "anthropic-version": "2023-06-01",
                     "content-type": "application/json"},
            json={"model": ANTHROPIC_MODEL, "max_tokens": 900, "system": sysp,
                  "tools": [TOOL], "tool_choice": {"type": "tool", "name": "answer"},
                  "messages": [{"role": "user", "content": f"SOURCES:\n{block}\n\nQUESTION: {question}"}]},
            timeout=60)
        resp.raise_for_status()
        content = resp.json().get("content", [])
        data = next((b.get("input") for b in content if b.get("type") == "tool_use"), {}) or {}
    except Exception as e:
        import sys; print("answer error:", type(e).__name__, file=sys.stderr, flush=True)  # no repr — never log secrets
        return {"found": False, "answer": "Something went wrong — please try again.", "used": [], "sources": sources}
    used = set(data.get("used", []) or [])
    shown = [s for s in sources if s["n"] in used] or (sources if data.get("found") else [])
    return {"found": bool(data.get("found")), "answer": data.get("answer", ""), "used": sorted(used),
            "sources": shown}


app = Flask(__name__)
app.config["MAX_CONTENT_LENGTH"] = 256 * 1024


@app.route("/")
def home():
    return Response(PAGE, mimetype="text/html")


@app.route("/api/ask", methods=["POST"])
def api_ask():
    q = (request.get_json(force=True).get("question") or "").strip()[:600]
    if not q:
        return jsonify(error="Ask a question."), 400
    return jsonify(answer_question(q))


PAGE = """<!doctype html><html lang="en"><head><meta charset="utf-8">
<title>GritAI · Cited Answers — Construction & Remodeling</title>
<meta name="viewport" content="width=device-width,initial-scale=1">
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</style></head>
<body><div class="wrap">
<header>
 <div class="mark"><svg width="38" height="38" viewBox="0 0 38 38" fill="none"><rect x="1" y="1" width="36" height="36" rx="2" stroke="#2b303c"/><path d="M27 12.5A9 9 0 1 0 28 22H19" stroke="#ff5a2a" stroke-width="2.4" stroke-linecap="square"/><rect x="10.5" y="10.5" width="3" height="3" fill="#ff5a2a"/></svg></div>
 <div class="brand"><div class="co">GRIT<b>AI</b></div><div class="sub">Cited Answers</div></div>
 <div class="tags"><span class="tag hot">&#9656; Live</span><span class="tag">RAG</span><span class="tag">SDVOSB</span></div>
</header>
<section class="hero">
 <h1>Answers you can <em>trust</em> — every claim cited.</h1>
 <p>Ask about construction and home remodeling. The answer is grounded only in a curated knowledge base and cites the exact sources — and it says <b>"I don't know"</b> when the answer isn't there. No made-up facts.</p>
</section>
<div class="sec"><span class="num">01</span><span class="name">Ask</span><span class="rule"></span></div>
<div class="ask">
 <div class="field"><span class="car">&gt;_</span>
  <input id="q" placeholder="Do I need a permit to remove a wall?" autofocus>
  <button class="run" id="go" onclick="ask()">Ask &#9656;</button></div>
 <div class="ex" id="ex"></div>
</div>
<div class="out" id="out">
 <div class="sec"><span class="num">02</span><span class="name" id="anslabel">Answer</span><span class="rule"></span></div>
 <div class="ans" id="answer"></div>
 <div class="sec" id="srchead" style="display:none"><span class="num">03</span><span class="name">Sources</span><span class="rule"></span></div>
 <div class="src" id="sources"></div>
</div>
<footer><span>RAG · fastembed + Claude · grounded, cited, honest</span>
 <span class="sp"><a href="https://gritai.solutions">GRITAI SOLUTIONS</a> · 30-in-15 &#8470;10</span></footer>
</div><script>
const EXAMPLES=["Do I need a permit to remove a wall?","How much contingency should I budget for a remodel?",
 "What flooring is best for a bathroom?","How do I vet a contractor before hiring?","When should I replace my roof?",
 "What's the best paint color for resale?"];
const $=id=>document.getElementById(id);const q=$('q'),go=$('go'),out=$('out');
function esc(s){return String(s==null?'':s).replace(/[&<>]/g,c=>({'&':'&amp;','<':'&lt;','>':'&gt;'}[c]));}
$('ex').innerHTML=EXAMPLES.map(e=>'<span class="chip">'+esc(e)+'</span>').join('');
$('ex').querySelectorAll('.chip').forEach(c=>c.onclick=()=>{q.value=c.textContent;ask();});
function citelink(s){return esc(s).replace(/\\[(\\d+)\\]/g,'<a class="ct" href="#src$1">[$1]</a>');}
function ask(){if(go.disabled)return;const text=q.value.trim();if(!text){q.focus();return;}
 go.disabled=true;go.textContent='…';out.classList.add('show');$('srchead').style.display='none';
 $('answer').innerHTML='<span class="spin"><span></span><span></span><span></span></span>';$('sources').innerHTML='';
 fetch('/api/ask',{method:'POST',headers:{'Content-Type':'application/json'},body:JSON.stringify({question:text})})
 .then(r=>r.json()).then(d=>{
  if(d.error){$('answer').textContent=d.error;return;}
  const miss=!d.found;$('answer').className='ans'+(miss?' miss':'');
  $('anslabel').textContent=miss?'Not in the knowledge base':'Answer';
  $('answer').innerHTML=citelink(d.answer||'');
  const src=d.sources||[];
  if(src.length){$('srchead').style.display='flex';
   $('sources').innerHTML=src.map(s=>'<div class="srow" id="src'+s.n+'"><span class="sn">['+s.n+']</span>'+
     '<div><div class="st">'+esc(s.title)+'</div><div class="sx">'+esc(s.text)+'</div></div></div>').join('');}
 }).catch(()=>{$('answer').textContent='Something went wrong — please try again.';})
 .finally(()=>{go.disabled=false;go.textContent='Ask \\u25b8';});
}
q.addEventListener('keydown',e=>{if(e.key==='Enter')ask();});
</script></body></html>"""


if __name__ == "__main__":
    backend = "Claude API" if ANTHROPIC_KEY else "NO KEY (retrieval only)"
    print(f"RAG Q&A with Citations on http://127.0.0.1:{PORT}  [backend: {backend}]", flush=True)
    app.run(host="0.0.0.0", port=PORT, threaded=True)