LeetAgent (AgentPrep)

LeetCode-style prep for agentic coding interviews: broken repo in a timed cloud sandbox, solve it in a browser-hosted IDE (Monaco editor + file tree + terminal + built-in Claude agent chat), and pytest is the grader. No SSH, no external tools — everything runs in one page.

Stack

• Next.js (App Router) + TypeScript + Tailwind v4
• Supabase Cloud (Postgres + Auth + RLS) — no Docker required
• E2B sandboxes (e2b JS SDK)

Supabase (hosted) — one-time setup

1. Create a project at supabase.com/dashboard (or use supabase projects list / supabase projects create after CLI login).

2. Log in and link the CLI (from this repo root):

   supabase login
   npm run db:link

   When prompted, paste your project ref (Settings → General → Reference ID).

   Non-interactive CI: set SUPABASE_ACCESS_TOKEN and run
   supabase link --project-ref <ref>.

3. Apply the database schema (runs supabase/migrations/* on the linked project):

   npm run db:push

4. Load the 10 curated problems — pick one:

   • SQL Editor (Dashboard → SQL): paste the contents of supabase/seed.sql and run once (idempotent upserts; safe to re-run).
   • Or after the Next app is configured, call POST /api/problems/ingest with x-admin-secret (uses the service role).

5. GitHub OAuth (Dashboard → Authentication → Providers → GitHub):

   • Add your GitHub OAuth App’s client ID and secret.
   • Redirect URL in GitHub’s app settings must include Supabase’s callback, e.g.
     https://<project-ref>.supabase.co/auth/v1/callback (see Auth URL on the provider page).
   • Under URL configuration, set Site URL to your deployed app (e.g. https://your-app.vercel.app) and add Redirect URLs for
     http://localhost:3000/**, http://127.0.0.1:3000/**, and your production /auth/callback as needed.

6. Next.js env — Project Settings → API: copy Project URL, anon public, and service_role into .env.local (see .env.example).

NPM scripts

Script	Purpose
npm run db:link	Link this folder to your Supabase project (supabase link)
npm run db:push	Push migrations to the linked cloud database
npm run db:generate-seed	Regenerate supabase/seed.sql from data/curated-problems.json
npm run db:types	Generate lib/database.types.ts from the linked DB (optional)

App commands

• npm run dev — local dev
• npm run build / npm run start — production

E2B & grading

• Set E2B_API_KEY in .env.local.
• From the repo root run npm run e2b:template once (builds the agentprep-sandbox image: Python 3, pip, compilers, common -dev libs). Then set E2B_SANDBOX_TEMPLATE=agentprep-sandbox in .env.local.

Grading: submit applies test_patch_diff with git apply, then python3 -m pytest <test_patch> …. The diff is not applied during the session.

Agent chat

The in-browser chat is powered by the Anthropic SDK. Set ANTHROPIC_API_KEY in .env.local (the key stays server-side). This is open-source — self-host and bring your own key.

API

Method	Path	Purpose
POST	/api/sessions/start	Start sandbox session
POST	/api/sessions/submit	Grade and tear down sandbox
GET	/api/sessions/[id]/status	Session status
POST	/api/sandbox/files/tree	List files in the session sandbox
POST	/api/sandbox/files/read	Read a file from the sandbox
POST	/api/sandbox/files/write	Write a file in the sandbox
POST	/api/sandbox/exec	Stream stdout/stderr from a command in the sandbox
POST	/api/agent/chat	Stream an Anthropic tool-use agent wired to the sandbox
POST	/api/problems/ingest	Upsert curated problems (admin secret)

Optional: supabase/config.toml

That file is mainly for the Supabase CLI (migrations path, optional local tools). Hosted Auth is configured in the Supabase Dashboard, not by committing secrets into config.toml.