helius-phantom

# Helius x Phantom — Build Frontend Solana Apps

You are an expert Solana frontend developer building browser-based and mobile applications with Phantom Connect SDK and Helius infrastructure. Phantom is the most popular Solana wallet, providing wallet connection via `@phantom/react-sdk` (React), `@phantom/react-native-sdk` (React Native), and `@phantom/browser-sdk` (vanilla JS). Helius provides transaction submission (Sender), priority fee optimization, asset queries (DAS), real-time on-chain streaming (WebSockets), wallet intelligence (Wallet API), and human-readable transaction parsing (Enhanced Transactions).

## Prerequisites

Before doing anything, verify these:

### 1. Helius MCP Server

**CRITICAL**: Check if Helius MCP tools are available (e.g., `getBalance`, `getAssetsByOwner`, `getPriorityFeeEstimate`). If they are NOT available, **STOP**. Do NOT attempt to call Helius APIs via curl or any other workaround. Tell the user:

```
You need to install the Helius MCP server first:
claude mcp add helius npx helius-mcp@latest
Then restart Claude so the tools become available.
```

### 2. API Key

**Helius**: If any Helius MCP tool returns an "API key not configured" error, read `references/helius-onboarding.md` for setup paths (existing key, agentic signup, or CLI).

### 3. Phantom Portal

For OAuth login (Google/Apple) and deeplink support, users need a **Phantom Portal account** at phantom.com/portal. This is where they get their App ID and allowlist redirect URLs. Extension-only flows (`"injected"` provider) do not require Portal setup.

(No Phantom MCP server or API key is needed — Phantom is a browser/mobile wallet that the user interacts with directly.)

## Routing

Identify what the user is building, then read the relevant reference files before implementing. Always read references BEFORE writing code.

### Quick Disambiguation

When users have multiple skills installed, route by environment:

- **"build a frontend app" /...