examples

@mppsol/agent examples

Two clients for an MPP-protected endpoint, one per settlement scheme.

File	Mode	When to use
pay-direct.ts	solana-direct (one-shot)	First payment to a server, or low-frequency calls. No on-chain setup needed.
pay-session.ts	solana-session (streamed debits)	High-frequency calls. Requires a session opened on-chain first.

Both expect a server running at MPP_URL (default http://localhost:3000/joke). Spin one up with /Users/hiroyusai/src/mppsol-server/examples/hono.ts.

pay-direct.ts

Pays by building a Solana tx (USDC transfer + Memo nonce binding) using @solana/web3.js. The agent SDK does not include a transaction builder for direct mode — you bring your own Solana SDK.

Setup

npm install @solana/web3.js @solana/spl-token bs58
spl-token create-account 4zMMC9srt5Ri5X14GAgXhaHii3GnPAEERYPJgZJDncDU --url devnet
spl-token transfer ... # fund yourself from a devnet faucet first

Run

export MY_USDC_ATA=<your-devnet-usdc-token-account>
bun run examples/pay-direct.ts

What you'll see

Status: 200
Body: Why don't scientists trust atoms? Because they make up everything.
Receipt: Payment scheme="solana-direct", tx="...", slot="...", ...

pay-session.ts

Signs an off-chain debit message — no Solana SDK needed (Ed25519 via @noble/curves, already a dep of @mppsol/agent).

Setup

You need a session opened on devnet first. Run the cpi example:

cd /Users/hiroyusai/src/mppsol-cpi
bun run examples/open-session.ts
# ...prints the session PDA pubkey and writes ./authorized-signer.json

Note the printed session pubkey, then in the agent example:

export MPPSOL_SESSION=<session-pda>
export SIGNER=/Users/hiroyusai/src/mppsol-cpi/authorized-signer.json
bun run examples/pay-session.ts

What you'll see

Same 200 + body + receipt as direct mode, but with scheme="solana-session" and a sequence field in the receipt. Server-side, no on-chain tx happens per request — settlement is batched by the server.

Production notes

• For pay-direct, persist nothing — each request issues a fresh nonce.
• For pay-session, the sequence number must be strictly monotonic per session. The example writes .session-seq to disk; production should use a database with row-level locking (e.g. Postgres UPDATE ... RETURNING) so concurrent agents don't reuse sequences.