# climate.stripe.dev

[Stripe Climate](https://stripe.com/climate) helps emerging permanent carbon removal technologies launch and scale. Agents can contribute to Stripe Climate using protocols like [MPP](https://mpp.dev) and [x402](https://x402.org).

## How to contribute

This example shows how to contribute a specified amount in USDC cents.

### `POST /api/contribute`

**Request body** (JSON, required):

```json
{
  "amount": 100
}
```

- `amount` (integer, required): Contribution amount in cents. Must be between 1 and 10000.

**Initial response** — `402 Payment Required`:

The server returns both an x402 challenge (`PAYMENT-REQUIRED` header) and an MPP challenge (`WWW-Authenticate: Payment` header). The client should create a payment payload using either protocol and retry the request.

- x402: pay with USDC on Base (eip155:8453). Retry with `payment-signature` header.
- MPP: pay with USDC on Tempo (eip155:42431). Retry with `Authorization: Payment` header.

**Success response** — `200 OK`:

```json
{
  "amount": 100,
  "contribution_id": "contrib_1A2B3C4D5E6F",
  "impact": "This contribution funds ~2.67kg of permanent carbon removal"
}
```

- `amount` (integer): The contributed amount in cents.
- `contribution_id` (string): Unique identifier for the contribution.
- `impact` (string): Human-readable description of the environmental impact.

**Error responses**:

- `400` — Invalid or missing JSON body, or `amount` not an integer between 1 and 10000.
- `402` — Payment required. Includes protocol challenge headers.

### Example

```shell
# Initial request
curl -i -X POST https://climate.stripe.dev/api/contribute \
  -H "Content-Type: application/json" \
  -d '{"amount": 100}'

# Response: 402 Payment Required
WWW-Authenticate: Payment challenge="eyJ0eXAiOiJKV1QiLCJhbGc..."

# Retry with MPP payment credentials
curl -X POST https://climate.stripe.dev/api/contribute \
  -H "Content-Type: application/json" \
  -H "Authorization: Payment proof=eyJ0eXAiOiJKV1Qi..." \
  -d '{"amount": 100}'

# Response: 200 OK
{
  "amount": 100,
  "contribution_id": "contrib_1A2B3C4D5E6F",
  "impact": "This contribution funds ~2.67kg of permanent carbon removal"
}
```

## Monetize your service

View the machine payments docs at https://docs.stripe.com/payments/machine

## Disclaimer

Stripe contributes 100% of your funds towards carbon removal projects, minus any fees charged by third parties. Contributions are not tax deductible because Stripe is not a registered charity. [Privacy Policy](https://stripe.com/privacy)