File Agent

An AI agent that navigates construction project documents like a filesystem — thinking in bash, not vectors.

Note: The application UI, all documents, and agent responses are in German, targeting German-speaking construction professionals. This README is in English.

Live Demo

Try it here -- No SSL (self-hosted on a VPS without a custom domain).

Architectural Thesis

For document collections with natural hierarchy (like construction projects), filesystem navigation produces more auditable results than embedding-based retrieval.

Construction projects have well-established document hierarchies — contracts, change orders, meeting minutes, punch lists, correspondence, daily logs, invoices, permits. These map naturally to folder structures with numeric prefixes:

/01_vertraege/ # Contracts
/02_nachtraege/ # Change orders
/03_genehmigungen/ # Permits
/04_protokolle/ # Meeting minutes
/05_maengel/ # Punch lists / defects
/06_schriftverkehr/ # Correspondence
/07_bautagebuch/ # Daily construction logs
/08_plaene/ # Technical drawings
/09_rechnungen/ # Invoices

The agent executes bash commands (ls, cat, grep, find) against a virtual in-memory filesystem built from these documents. Every navigation step is visible to the user — the trace IS the evidence. There is no vector database, no embeddings, no RAG pipeline. Just bash.

This approach trades recall breadth for auditability: you can see exactly which documents the agent opened, which search terms it used, and how it arrived at its answer. For domains with structured document hierarchies, this transparency is more valuable than statistical similarity scores.

Features

• Virtual filesystem with realistic German construction documents (PDF, Excel, text, SVG drawings)
• AI agent navigates via bash commands (ls, cat, grep, find)
• Real-time streaming responses with visible command trace
• Inline citations referencing source documents
• Evaluation harness with A/B testing capability
• All documents in German construction terminology (VOB, HOAI, etc.)

Tech Stack

Technology	Version	Purpose
Next.js	16	App Router, SSR, deployment
AI SDK	6	Agent loop, streaming, tool orchestration
@ai-sdk/anthropic	3	Claude model provider
just-bash + bash-tool	2 / 1	Virtual in-memory filesystem + bash interpreter
Tailwind CSS	4	Styling
Vitest	4	Testing
TypeScript	5	Type safety

Try It

Once running, try these example questions (in German):

• "Welche Nachtraege gibt es und was ist deren aktueller Status?" — Lists all change orders and their current status
• "Welche Maengel sind noch nicht behoben?" — Finds unresolved defects across punch lists
• "Wer sind die beteiligten Nachunternehmer und welche Gewerke fuehren sie aus?" — Identifies subcontractors and their trades

Local Setup

git clone https://github.com/USER/file-agent.git
cd file-agent
npm install
cp .env.example .env.local
# Add your ANTHROPIC_API_KEY to .env.local
npm run dev
# Open http://localhost:3000

Deployment

Pre-deploy checks

npm run build
npm test

Option A: Self-hosted with Coolify (recommended)

The live demo uses Coolify on a self-hosted VPS. This avoids serverless function timeouts — the agent runs multi-step bash navigation loops that can take 15-30 seconds, which exceeds Vercel's Hobby plan limits.

1. Install Coolify on any VPS (1 vCPU, 2 GB RAM is sufficient)
2. Add the GitHub repo as a new resource (Nixpacks build pack)
3. Set ANTHROPIC_API_KEY as an environment variable
4. Deploy — Coolify auto-detects Next.js and handles build/start

Note: The live demo runs on HTTP via a free sslip.io domain. For HTTPS, point a custom domain to the VPS and Coolify will auto-provision a Let's Encrypt certificate.

Option B: Vercel

The codebase is standard Next.js and deploys to Vercel with zero code changes. Connect the GitHub repo in the Vercel Dashboard, or deploy via CLI:

npx vercel deploy --prod

Set ANTHROPIC_API_KEY in Vercel Dashboard > Project Settings > Environment Variables.

Note: Vercel Pro plan (60s function timeout) is recommended. The Hobby plan's 10-second timeout may cut off multi-step agent responses.

Runtime Notes

• Edge runtime is not supported — just-bash uses Node.js APIs internally. The default Node.js serverless runtime is required.
• Streaming keeps the connection alive — both Vercel and Coolify support streamed responses natively.

Project Structure

src/
app/ # Next.js App Router pages and API routes
components/ # Chat UI, tool trace, citations, example questions
corpus/ # Virtual filesystem data and loader
lib/agent/ # System prompt and agent configuration
eval/ # Evaluation harness, test questions, A/B comparison
docs/ # Architecture diagrams (Excalidraw)