> For the complete documentation index, see [llms.txt](https://docs.january.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.january.ai/client-sdks/ios-sdk/reference/client-and-resources.md).

# Client and resources

`JanuaryClient` is the SDK's entry point.

## Create a client

```swift
let client = try JanuaryClient(
    endUserID: endUserID,
    timezone: TimeZone.current,
    clientTokenProvider: tokenProvider
)
```

## Initializers

| Parameters                                                                                 | Use                                                                                                                     |
| ------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------- |
| `endUserID, timezone?, clientTokenProvider: any JanuaryTokenProvider, tokenRetryPolicy?`   | Production: a named provider type that calls your token endpoint                                                        |
| `endUserID, timezone?, clientTokenProvider: JanuaryClientTokenProvider, tokenRetryPolicy?` | Production: the same, as an `async` closure                                                                             |
| `clientToken, endUserID, timezone?`                                                        | One token your app manages; create a new client to replace it                                                           |
| `developmentAPIKey, endUserID, timezone?`                                                  | Local Debug builds only ([local development](/client-sdks/ios-sdk/getting-started/authentication.md#local-development)) |

Every initializer requires a non-empty `endUserID`; a blank one throws an `.authentication` error with the code `invalid_end_user_id`. [User identity and timezone](/client-sdks/ios-sdk/concepts/user-identity-and-timezone.md) covers `endUserID` and `timezone`.

Every initializer targets `https://partners.january.ai`. There's no public base-URL or token-endpoint override.

## Resource methods

These are the methods on a `JanuaryClient`'s resources. Each resource also has request-value forms, such as `create(_ request: CreateFoodLogRequest)`; the resource pages list them.

| Resource       | Method                                     | Purpose                                                     |
| -------------- | ------------------------------------------ | ----------------------------------------------------------- |
| `foods`        | `autocomplete(_:)`                         | Type-ahead suggestions                                      |
| `foods`        | `search(_:)`                               | Search foods by name                                        |
| `foods`        | `lookupBarcode(_:)`                        | Look up a UPC, EAN, or GTIN barcode                         |
| `foods`        | `get(id:)`                                 | Fetch the full food with every serving                      |
| `foods`        | `suggestAlternatives(_:)`                  | Find alternatives that fit dietary needs                    |
| `restaurants`  | `search(_:)`                               | Find nearby restaurants                                     |
| `restaurants`  | `searchMenuItems(_:)`                      | Find nearby menu items                                      |
| `restaurants`  | `getMenuItems(_:)`                         | Load a restaurant's menu by the ID from a restaurant search |
| `foodAnalysis` | `analyzePhoto(_:)`                         | Analyze a meal photo                                        |
| `foodAnalysis` | `analyzeDescription(_:)`                   | Analyze a meal description                                  |
| `foodAnalysis` | `correct(_:)`                              | Correct an analysis with a text instruction                 |
| `foodLogs`     | `create(foods:timestampUTC:name:)`         | Create a food log                                           |
| `foodLogs`     | `list(start:end:)`                         | List food logs for a date range                             |
| `foodLogs`     | `getSummary(start:end:groupBy:weekStart:)` | Summarize food logs per day or week                         |
| `foodLogs`     | `get(id:)`                                 | Get one food log                                            |
| `foodLogs`     | `update(id:foods:timestampUTC:name:)`      | Update a food log                                           |
| `foodLogs`     | `delete(id:)`                              | Delete a food log                                           |
| `waterLogs`    | `create(amount:consumedAtUTC:)`            | Log an amount of water                                      |
| `waterLogs`    | `list(start:end:unit:)`                    | Daily water totals for a date range                         |
| `waterLogs`    | `delete(id:)`                              | Delete a water log                                          |
| `weightLogs`   | `create(weight:measuredAtUTC:)`            | Log a weight                                                |
| `weightLogs`   | `list(start:end:)`                         | Each day's latest weight for a date range                   |
| `glucose`      | `predict(_:)`                              | Predict a glucose curve                                     |

Every method is `async throws`. It throws `JanuaryError`, or `CancellationError` when its task is canceled ([Errors](/client-sdks/ios-sdk/reference/error-handling.md)).

## Identifiers

The SDK wraps identifiers in types so they can't be mixed up: `PartnerUserID`, `FoodID`, and `ServingID`.

## Response types

| Operation                                        | Response                            |
| ------------------------------------------------ | ----------------------------------- |
| Food autocomplete                                | `AutocompleteFoodsResponse`         |
| Food search or barcode lookup                    | `FoodSearchResults`                 |
| Full food (`foods.get`)                          | `FoodSearchItem`                    |
| Food analysis: photo, description, or correction | `FoodScan`                          |
| Food alternatives                                | `SuggestFoodAlternativesResponse`   |
| Restaurant search                                | `SearchRestaurantsResponse`         |
| Menu-item search                                 | `SearchRestaurantMenuItemsResponse` |
| Restaurant menu                                  | `GetRestaurantMenuItemsResponse`    |
| Food-log create, get, or update                  | `FoodLog`                           |
| Food-log list                                    | `ListFoodLogsResponse`              |
| Food-log summary                                 | `FoodLogSummary`                    |
| Water-log create                                 | `WaterLog`                          |
| Water-log list                                   | `ListWaterLogsResponse`             |
| Weight-log create                                | `WeightLog`                         |
| Weight-log list                                  | `ListWeightLogsResponse`            |
| Glucose prediction                               | `GlucosePrediction`                 |