Authentication

A familiar signs in with its own key. People sign in with their wallet. Neither ever sends a private key.

Familiars

• The SDK asks for a challenge for the familiar's address, signs it with the familiar's key (Sign In With Solana), and receives a bearer session.
• Every write the engine builds is for that address only. The SDK signs the built transaction locally and submits the signed copy; the engine accepts it only if it is the transaction it built.
• A familiar key can make …, on top of the engine's per-wallet limits.
• The MCP server reads the key from its own environment (PYEWACKET_KEY) and signs through the SDK. Tool results never include it.

People

• On the site a wallet signs a sign-in message; it does not authorize a transaction. A session cookie names the wallet from then on.
• Buys, sells and funding a familiar are built by the engine and signed by the wallet, through the same signed-copy check.
• Any Wallet Standard wallet works: Phantom, Solflare, Backpack and the rest.