> Feedback: If these docs are stale, missing, or confusing, post sanitized feedback to `https://docs.tempo.xyz/api/feedback` with `source: "mcp"`, a short `message`, and any relevant `toolName`, `relatedResource`, or `client`.
# Make Agentic Payments

Make agentic payments using the [Machine Payments Protocol](https://mpp.dev) (MPP). MPP adds inline payments to any HTTP endpoint — agents, apps, or humans pay as part of their request, and the server verifies payment before returning the response.

## Try it out

See the full payment flow in action. The terminal creates an ephemeral wallet, funds it with testnet USDG, and makes a paid request to fetch a photo.

<div style={{ height: 480 }}>
  <TerminalDemo />
</div>

## Payment flow

A client requests a paid resource, the server responds with `402` and a `Challenge` describing the price. The client pays, retries with a `Credential` transaction, and the server returns the resource with a `Receipt`.

<MermaidDiagram
  chart={`sequenceDiagram
  participant Client
  participant Server
  Client->>Server: (1) GET /resource
  Server-->>Client: (2) 402 Payment Required + Challenge
  Note over Client: (3) Client fulfills payment
  Client->>Server: (4) GET /resource + Credential
  Note over Server: (5) Server verifies payment
  Server-->>Client: (6) 200 OK + Receipt
`}
/>

1. **Request** — Any HTTP method (`GET`, `POST`, etc.)
2. **Challenge** — `402` with `WWW-Authenticate: Payment` header describing amount, currency, and recipient
3. **Pay** — Client signs a transaction or fulfills payment off-chain
4. **Retry** — Client re-sends with `Authorization: Payment` header containing the Credential
5. **Deliver** — Server verifies, returns `200` with `Payment-Receipt` header

## Why Tempo

Tempo's transaction model is designed for agentic payments using MPP:

* **~500ms finality** — Deterministic confirmation fast enough for synchronous request/response flows
* **Sub-cent fees** — Low enough for micropayments and per-request billing
* **Fee sponsorship** — Servers can cover gas on behalf of clients so they only need stablecoins
* **2D and expiring nonces** — Parallel nonce lanes prevent payment transactions from blocking other account activity
* **High throughput** — Supports the on-chain settlement volume that payment channels generate at scale

## Payment intents

Two [intents](https://mpp.dev/protocol#payment-intents) are available on Tempo:

| | **Charge** | **Session** |
|---|---|---|
| **Pattern** | One-time payment per request | Continuous pay-as-you-go |
| **Latency** | ~500ms (on-chain confirmation) | Near-zero (off-chain vouchers) |
| **Best for** | Single API calls, content access, one-off purchases | LLM APIs, metered services, usage-based billing |
| **On-chain cost** | Per request | Amortized across many requests |

## Use cases

* **Paid APIs** — Charge per request without API keys, billing accounts, or signup flows.
* **MCP tools** — Monetize tool calls served through the Model Context Protocol. Agents pay per call without OAuth or account setup.
* **Digital content** — Charge per access for articles, data feeds, or media without subscription paywalls.

## Get started

<Cards>
  <Card icon="lucide:user" title="Client quickstart" description="Handle payment-gated resources automatically" to="/docs/guide/machine-payments/client" />

  <Card icon="lucide:bot" title="Agent quickstart" description="Discover services and make paid requests from a terminal or AI agent" to="/docs/guide/machine-payments/agent" />

  <Card icon="lucide:search" title="Discover MPP services" description="Find paid APIs through the mpp.dev directory, catalog API, and MCP server" to="/docs/guide/machine-payments/discover-services" />

  <Card icon="lucide:server" title="Server quickstart" description="Add payment gating to your HTTP endpoints" to="/docs/guide/machine-payments/server" />

  <Card icon="lucide:credit-card" title="Accept one-time payments" description="Charge per request with on-chain settlement" to="/docs/guide/machine-payments/one-time-payments" />

  <Card icon="lucide:repeat" title="Accept pay-as-you-go payments" description="Session-based billing with off-chain vouchers" to="/docs/guide/machine-payments/pay-as-you-go" />
</Cards>

## SDKs and tools

| Tool | Package | Install |
|-----|---------|---------|
| CLI | [`tempo request`](/docs/cli/request) | `curl -fsSL https://tempo.xyz/install \| bash` |
| TypeScript | [`mppx`](https://github.com/wevm/mppx) | `npm install mppx viem` |
| Python | [`pympp`](https://github.com/tempoxyz/pympp) | `pip install pympp` |
| Rust | [`mpp-rs`](https://github.com/tempoxyz/mpp-rs) | `cargo add mpp` |

See the [full SDK documentation](https://mpp.dev/sdk) for API reference and advanced usage.

## Learn more

* [MPP documentation](https://mpp.dev) — Full protocol docs, SDK reference, and guides
* [IETF specs](https://paymentauth.org/) — Normative protocol specification
* [Protocol overview](https://mpp.dev/protocol) — Challenges, Credentials, Receipts, and transports