Phantom Skill

Build frontend Solana applications with Phantom Connect SDK and Helius infrastructure. Covers React, React Native, and browser SDK integration, transaction signing, token gating, NFT minting, payments, and secure frontend architecture.

The Phantom skill makes your AI assistant an expert at building frontend Solana applications. It combines Phantom Connect SDK — React, React Native, and vanilla JS wallet integration — with Helius infrastructure for transaction submission, fee optimization, asset queries, and real-time updates.

When installed, the AI automatically reads the right reference files and calls the right MCP tools based on what you ask — no manual tool selection needed.

Claude Code: /helius:phantom (via plugin) or auto-invoked (standalone). Codex: $helius-phantom (auto-discovered from .agents/skills/). API / Cursor / ChatGPT: Use the pre-built system prompt variants.

What It Covers

The Phantom skill routes the AI across both Phantom SDKs and Helius tools:

Domain	Reference Files	MCP Tools Used
Wallet Connection — React	react-sdk.md	—
Wallet Connection — Browser	browser-sdk.md	—
Wallet Connection — React Native	react-native-sdk.md	—
Transactions	transactions.md, helius-sender.md	getPriorityFeeEstimate, getSenderInfo
Token Gating	token-gating.md, helius-das.md	getAssetsByOwner, searchAssets, getAsset
NFT Minting	nft-minting.md, helius-sender.md	getAsset, getPriorityFeeEstimate
Crypto Payments	payments.md, helius-enhanced-transactions.md	parseTransactions, getPriorityFeeEstimate
Frontend Security	frontend-security.md	—
Portfolio Display	helius-das.md, helius-wallet-api.md	getAssetsByOwner, getWalletBalances, getTokenBalances
Real-Time Updates	helius-websockets.md	transactionSubscribe, accountSubscribe
Transaction History	helius-enhanced-transactions.md	parseTransactions, getTransactionHistory
Integration Patterns	integration-patterns.md	Multiple (pattern-dependent)

Key Rules

The Phantom skill enforces critical patterns that prevent common frontend mistakes:

• Always use @phantom/react-sdk for React (never window.phantom.solana or @solana/wallet-adapter-react)
• Always use @phantom/browser-sdk for vanilla JS and @phantom/react-native-sdk for React Native
• Never expose Helius API keys in client code — only https://sender.helius-rpc.com/fast is browser-safe without an API key
• Proxy everything else through your backend — never open Helius WebSockets directly from the browser
• Always submit transactions via Helius Sender with skipPreflight: true, maxRetries: 0, and a Jito tip
• Use getPriorityFeeEstimate MCP tool — never hardcode priority fees

Composite Patterns

The skill provides five end-to-end reference patterns for complex applications:

1. Swap UI — Aggregator → Phantom sign → Helius Sender submit
2. Portfolio Viewer — Phantom connection → backend proxy → DAS/Wallet API
3. Real-time Dashboard — Phantom connection → server WebSocket → client relay
4. Token Transfer — Build VersionedTransaction → Phantom sign → Sender submit
5. NFT Gallery — Phantom wallet → backend DAS query → display NFTs

Prerequisites

This skill requires the Helius MCP server. For embedded wallets (Google/Apple sign-in), you also need a Phantom Portal account with an App ID and allowlisted redirect URLs.

If you install via the Claude Code plugin, the MCP server starts automatically. For standalone installation, add it manually:

claude mcp add helius npx helius-mcp@latest

Standalone Installation

If you want the Phantom skill without the full plugin, install it directly:

1. Clone the repository

   git clone https://github.com/helius-labs/core-ai.git
   cd core-ai/helius-skills/helius-phantom
   
2. Run the install script

   ./install.sh
   

   This installs the skill and its reference files to ~/.claude/skills/helius-phantom/.

   Options:

   • ./install.sh --project — install to the current project (.claude/skills/helius-phantom/)
   • ./install.sh --path /custom/path — install to a custom directory
3. Install the Helius MCP server

   claude mcp add helius npx helius-mcp@latest
   
4. Set your API key

   export HELIUS_API_KEY=YOUR_API_KEY
   

   Or use the setHeliusApiKey MCP tool inside Claude Code. If you need a new account, see Helius CLI or use the autonomous signup flow via MCP tools.

Example Prompts

Once installed, ask in plain English:

• “Build a swap UI with Phantom wallet”
• “Build a portfolio viewer that shows tokens after connecting Phantom”
• “How do I proxy my Helius API key in Next.js?”
• “Build a real-time dashboard with wallet connection”
• “Add token gating to my React app using Phantom”
• “Build an NFT minting page with Phantom and Metaplex Core”

The AI picks the right tools and reads the right reference files automatically.

What’s Included

The skill installs two components:

• SKILL.md — Routing logic, rules, and expert context that guide the AI’s behavior
• prompts/ — Pre-built system prompt variants (openai.developer.md, claude.system.md, full.md) — see platform setup
• references/ — 16 deep documentation files:
  • react-sdk.md — Phantom React SDK (@phantom/react-sdk)
  • browser-sdk.md — Phantom Browser SDK (@phantom/browser-sdk)
  • react-native-sdk.md — Phantom React Native SDK (@phantom/react-native-sdk)
  • transactions.md — Transaction signing patterns
  • token-gating.md — Token-gated access control
  • nft-minting.md — NFT minting with Phantom
  • payments.md — Crypto payment flows
  • frontend-security.md — API key proxying and CORS
  • integration-patterns.md — End-to-end composite patterns
  • helius-das.md — DAS API reference
  • helius-sender.md — Sender reference
  • helius-priority-fees.md — Priority fee reference
  • helius-wallet-api.md — Wallet API reference
  • helius-websockets.md — WebSocket reference
  • helius-enhanced-transactions.md — Enhanced Transactions reference
  • helius-onboarding.md — Account setup reference

Learn More

Helius MCP

The MCP server that powers this skill’s tools

Claude Code Plugin

One-click install of MCP + skills

Build Skill

General Solana development with Helius

GitHub

Source code and issue tracking