The protocol AI agents pay vault operators through.
An x402 + RAG multi-vault network on Solana. Anyone mounts a markdown corpus, AI agents settle USDC per cited snippet, payouts route directly to the operator's Solana address — Brain Drain custodies nothing.
Live · Mount your vault · Architecture · Frontier submission
Open-web training data is exhausted. Valuable context — researchers' notebooks, engineers' war stories, lawyers' precedent files, traders' edge cases — lives in private vaults. Agents either hallucinate around it or scrape it without consent; the experts who curated it get nothing back.
There has never been a frictionless rail for an agent to pay the human whose knowledge it just used.
Brain Drain is not the marketplace — it's the protocol the marketplace runs on. v0 is a multi-vault network on Solana devnet.
Operator path. Connect Phantom, sign a one-shot challenge, drop a markdown bundle at /vaults/new. Brain Drain chunks + embeds (Gemini 3072d), persists the index in Supabase Storage, registers the vault with the operator's payout address + category. The vault gets a public x402-gated endpoint at /api/v/{slug}/query and a discovery page.
Buyer path. An agent (Claude Desktop, Cursor, MCP client, raw HTTP) hits the endpoint. 402 Payment Required returns USDC price + the operator's payout address. The agent's CDP Embedded Wallet auto-funds, signs an SPL transfer, retries with X-Payment proof. Helius RPC verifies the transfer in ~400 ms. Top-k snippets + citations + tx signature return. USDC lands in the operator's wallet — Brain Drain custodies nothing.
Devnet by choice for v0; mainnet cutover is one env flip. Protocol logic is identical across networks.
sequenceDiagram
autonumber
actor Operator
participant UI as /vaults/new
participant Auth as /api/auth
participant Reg as /api/vaults
participant Store as Supabase
participant Buyer as AI Agent
participant CDP as CDP Wallet
participant Vault as /api/v/{slug}/query
participant Sol as Solana
Note over Operator,Store: Mount (one-time)
Operator->>Auth: Phantom signMessage(nonce)
Auth-->>Operator: HMAC session cookie (1 h)
Operator->>UI: Pick category + drop markdown
UI->>Reg: POST /api/vaults
Reg->>Store: chunk + embed + register
Store-->>Operator: Vault live at /vaults/{slug}
Note over Buyer,Sol: Settle (per query)
Buyer->>Vault: POST {query}
Vault-->>Buyer: 402 {price, payTo: operator}
Buyer->>CDP: signAndSend USDC SPL
CDP->>Sol: settlement
Buyer->>Vault: POST {query} + X-Payment
Vault->>Sol: verify (Helius parsed-tx)
Vault-->>Buyer: 200 {snippets, sources, txHash}
Component-level detail in docs/architecture.md.
Public catalog at /vaults. Every upload picks one of 8 categories: engineering, trading, defi, research, productivity, design, legal, other. Free-form tags (max 8, normalized) carry long-tail nuance.
Vault depth standard: every chunk should be specific enough that an agent would pay $0.05 to read it. Real dates, real tickers/versions, real error messages, real outcomes.
| Layer | Choice |
|---|---|
| Frontend | Next.js 16 App Router · React 19 · Tailwind CSS 4 · Framer Motion 12 · Turbopack |
| Backend | Vercel serverless · Supabase Postgres + Storage (eu-central-1) · Postgres-backed token-bucket rate limiter · Zod 4 |
| Auth | Sign-in-with-Solana — tweetnacl ed25519 + HMAC-SHA256 session cookies (1 h TTL) |
| Blockchain | Solana devnet · @solana/web3.js · @solana/spl-token · bs58 |
| RPC | Helius parsed-tx + signatures-for-address (~400 ms confirmed) |
| Payment | x402-next v1.2 (Coinbase × Cloudflare) · CDP Embedded Wallets (@coinbase/cdp-sdk MPC) · TransactionModifyingSigner |
| Agent | Anthropic MCP server (/api/mcp) — 4 paid tools · raw HTTP · @modelcontextprotocol/sdk v1.29 |
| RAG | Custom ~200 lines (no LangChain, no vector DB) · Gemini 3.1 Pro + gemini-embedding-001 3072d (in-memory cosine) · Vercel AI SDK |
| Payout | Operator's Solana address — Brain Drain never holds funds |
No Anchor / Rust. All on-chain logic is composed from existing primitives (SPL transfers, CDP MPC, x402, Helius parsed-tx). The novelty is in the wiring.
No vector DB. Per-vault index lives in Supabase Storage as JSON; in-process LRU caches 32 vaults for 5 min. Cosine top-k is a literal for loop. Submit-grade because it's small enough to read end-to-end in 5 minutes.
Submitted via arena.colosseum.org/u/Beks. Awaiting judging.
| Bounty | How |
|---|---|
| Best Multi-Protocol Agent Hub | x402 + CDP wallet + MCP server + Solana settlement chained into one route |
| Best x402 Integration | Reference implementation on Solana — full spec compliance, multi-vault per-operator routing, atomic distributed rate limit |
| Best CDP Embedded Wallets | Buyer-side MPC TransactionModifyingSigner — auto-fund + auto-sign, no raw-key handling |
| Best AgentPay Demo | 3-minute submission video — agentic settlement end-to-end with on-chain proof |
Also submitted to the Halborn security track (CSO audit + OWASP Top 10 mapping) and the Solana Foundation Turkey $3K builder grant.
Prerequisites: Bun ≥ 1.3, Helius API key, Coinbase CDP project (Wallet Secret), Google AI key (Gemini 3.1 Pro), Supabase project, 32-byte hex AUTH_SECRET.
git clone https://github.com/Bekirerdem/brain-drain.git
cd brain-drain
bun install
cp .env.example .env.local # fill keys, see comments
bun -e 'console.log(require("crypto").randomBytes(32).toString("hex"))' # AUTH_SECRET
# Apply Supabase migrations via dashboard or supabase CLI, then:
bun scripts/seed-vault-supabase.ts # seed a vault
bun scripts/multi-buyer-traffic.ts # (optional) organic settlement traffic
bun devRoutes:
/vaults— catalog, category filter/vaults/new— mount your bundle/vaults/{slug}— detail + liveVaultProbeWidget/dashboard— operator panelPOST /api/v/{slug}/query— paid x402-gated endpointPOST /api/mcp— Streamable HTTP MCP transport
11-day solo sprint, public commits from Day 0. Full plan in docs/roadmap.md.
- Day 0–2 — Repo, scaffold, markdown loader + Gemini RAG + x402 middleware
- Day 3–5 — CDP Embedded Wallet buyer flow, MCP server, end-to-end verified
- Day 6–7 — Frontend rebuild, multi-vault MVP, CSO audit
- Day 8–9 — Network seed + MCP v0.3, category taxonomy
- Day 10 — Frontier submission, OWASP Top 10 mapping
- Day 11–13 — Demo video, Halborn track submission, Foundation Turkey grant submission, Twitter announce
- Post-Frontier — Mainnet cutover, MCP catalog distribution (Smithery, Cursor, awesome-mcp-servers), operator outreach
Pre-submission CSO-grade audit. All 10 findings resolved — eight by patch, two by documented mitigation + scope-limit + post-submit migration plan.
| ID | Finding | Status |
|---|---|---|
| BD-01 | /api/vaults POST trust-the-body — vault impersonation |
✅ Sign-in-with-Solana (3c40bd5) |
| BD-02 | /api/vaults?owner= private vault leak |
✅ Session-gated owner branch (3c40bd5) |
| BD-03 | Phantom auth no signature verification | ✅ ed25519 nonce flow (3c40bd5) |
| BD-04 | Axios prototype pollution (transitive) | ✅ ^1.12.0 override → v1.13.6 |
| BD-05 | bigint-buffer overflow (transitive) | ✅ Scope-limited (read-only ATA derivation, no user bigint input); @solana/kit migration post-submit |
| BD-06 | No rate limit on expensive embeds | ✅ Supabase token-bucket (4d10331) |
| BD-07 | Waitlist PII in logs | ✅ SHA-256 redaction (740809f) |
| BD-08 | Supabase/Zod errors leaked | ✅ lib/errors.ts sanitize (ff5a6cd) |
| BD-09 | postcss XSS (build-time) | ✅ Override ≥8.5.10 (0abfbbe) |
| BD-10 | Missing security headers | ✅ X-Frame-Options DENY, nosniff, Permissions-Policy, Referrer-Policy (ff5a6cd) |
Second audit pass after Day 10's layout + ledger + theme changes (46837f7) → no new findings. New surfaces (vault_settlements trigger, ThemeProvider localStorage, GitHubStarButton fetch, theme CSS vars) — none reached authenticated paths.
| OWASP | Mapped controls |
|---|---|
| A01 Broken Access Control | BD-01, BD-02 — server-derived owner_wallet; /api/vaults?owner= session match; Postgres RLS on vaults + vault_settlements |
| A02 Cryptographic Failures | BD-03 + lib/auth/session.ts — tweetnacl.sign.detached.verify ed25519, HMAC-SHA256 with timingSafeEqual |
| A03 Injection | Zod parse at every API boundary, Supabase parameter-binding queries, no raw SQL concatenation |
| A04 Insecure Design | Ledger PK on signature → replay impossible; trigger keeps counters in lock-step; atomic per-key rate-limit buckets |
| A05 Security Misconfiguration | BD-10 — security headers in next.config.ts; service-role key server-only |
| A06 Vulnerable Components | BD-04, BD-09 — axios ^1.12.0, postcss ^8.5.10 overrides; npm ls clean. BD-05 documented mitigation |
| A07 Authentication Failures | BD-03 + challenge replay protection — 5-min nonce TTL, 1-h HMAC cookie, constant-time comparison |
| A08 Software & Data Integrity | BD-08 — coarse public errors, internal logs in Vercel; PRs require code-owner review (.github/CODEOWNERS) |
| A09 Logging & Monitoring | Structured console.error JSON in lib/errors.ts, lib/ratelimit.ts; rate-limit fail-open logs prefix |
| A10 SSRF | No user-controlled URL fetches; legacy RPC indexer reads only known Helius endpoints; GitHubStarButton hits literal repo URL |
bun scripts/smoke.ts— exits non-zero on regression across pages, REST endpoints, MCPtools/list, x402 quote, unauth POSTs. 16/16 passing.npm ls axios bigint-buffer postcss ip-address— confirms override resolutions.- Disclosure:
SECURITY.md· Repo entry-points:docs/agent-onboarding.md.
Hackathon submissions in — judging phase. Project continues post-Frontier. Issues, ideas, friendly heckling welcome — open a GitHub issue or DM @l3ekirerdem.
MIT © 2026 Bekir Erdem
Built solo for Colosseum Frontier 2026, supported by Superteam Earn's Agentic Engineering Grant. Built on CDP, Phantom, Helius, Supabase, Solana. x402 by Coinbase × Cloudflare · MCP by Anthropic · Gemini by Google DeepMind.
Development cadence shaped by solana.new — SendAI + Superteam's open-source platform. CSO audit ran on its cso skill.
Built in Bursa during the Kozalak-hosted DevPack Frontier 2026, alongside Snowball and AuraCast — three Solana protocols from one community node.
Brain Drain · solo build for Frontier 2026 · by Bekir Erdem
Repo · Frontier profile · X · GitHub