# Make your first API call

Connect your backend to your Thesauros partner account and read the data your product needs.

Start by reading your partner summary. It connects customer attribution, balances and partner economics in one response, so your team can see the integration working before adding customer actions.

To explore before you have a partner account, use the [sandbox quickstart](/start/sandbox/).

## 1. Set your connection details

Use the Partner API base URL and partner-scoped key supplied during onboarding. The base URL includes `/api/v1`. Keep the key on your backend.

```bash
export THESAUROS_API_BASE="https://your-assigned-api-host/api/v1"
export THESAUROS_API_KEY="your-partner-api-key"
```

`your-assigned-api-host` and `your-partner-api-key` are values to replace. The public developer portal hosts a separate sandbox contract; its URL is not a default Partner API endpoint.

## 2. Read your partner summary

```bash
curl --fail-with-body \
  "$THESAUROS_API_BASE/partner/summary" \
  -H "Authorization: Bearer $THESAUROS_API_KEY"
```

A successful response contains an outer `object` and `data`. Inside `data`, you will find your partner identity, attributed user count, deposit totals, TVL, yield and revenue estimates. The `as_of` field gives the response's calculation time.

An account with no activity can return zero totals. Treat that as a valid empty state in your interface.

## 3. Read yield information

```bash
curl --fail-with-body \
  "$THESAUROS_API_BASE/yield/history/USDC" \
  -H "Authorization: Bearer $THESAUROS_API_KEY"
```

The returned series has `scope: "protocol"`. It describes the protocol's recorded APY for the asset, not the performance of an individual customer or partner. On a fresh deployment, `history` may be empty and `observations` may be zero.

APY fields use decimal fractions: `0.052` displays as `5.2%`. See [amounts and units](/build/units/) before formatting values in your product.

## 4. Connect the next part of your flow

| Product task | Next step |
| --- | --- |
| Link an app user to your partner account | [Customer attribution](/build/users/) |
| Show balances and activity | [Positions and activity](/build/activity/) |
| Receive signed events | [Webhooks](/build/webhooks/) |
| Build with typed clients | [SDKs](/sdks/) |
| Plan wallet transactions and go-live | [Launch your integration](/operate/launch/) |

## If your first request fails

`401` usually means the key is missing, invalid or revoked. `403` means the key cannot access this operation, or its partner context is unavailable. In particular, an administrative key does not substitute for a partner-bound key on `/partner/*`.

Use the [authentication guide](/build/authentication/) and [error reference](/build/errors/) to resolve the response before retrying.