> ## Documentation Index
> Fetch the complete documentation index at: https://hastekit.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Managing Multiple Keys

HasteKit supports managing multiple API keys for a single provider. This is useful for:

* **Load Balancing:** Distribute requests across multiple API keys to avoid rate limits.
* **Redundancy:** Ensure high availability by having fallback keys.
* **Cost Management:** Allocate traffic based on usage quotas or costs associated with different keys.

## Weighted Random Selection

When multiple API keys with weights are configured for a provider, HasteKit uses **weighted random selection** to choose which key to use for each request.

Each API key must be assigned a `Weight`. The probability of a key being selected is proportional to its weight relative to the sum of all weights for that provider.

### How it Works

1. HasteKit retrieves all the configured API keys for the requested provider.
2. It extracts the `Weight` from each `APIKeyConfig`.
3. If multiple keys exist, it performs a weighted random selection.
4. The request is then executed using the selected API key.

If all keys have the same weight (e.g., all set to `1` or not specified), the selection becomes uniformly random.

## Configuration Example

When using the HasteKit SDK in direct mode, you can configure multiple keys by passing a `[]hastekit.ProviderConfig` to `hastekit.NewLLMClient`, assigning each `APIKeyConfig` a `Weight`.

```go theme={null}
package main

import (
	hastekit "github.com/hastekit/hastekit-sdk-go"
)

func main() {
	// Define multiple API keys for OpenAI with different weights
	providerConfigs := []hastekit.ProviderConfig{{
		ProviderName: hastekit.ProviderOpenAI,
		ApiKeys: []*hastekit.APIKeyConfig{
			{
				APIKey: "sk-openai-key-1",
				Weight: 70, // This key will be used ~70% of the time
			},
			{
				APIKey: "sk-openai-key-2",
				Weight: 30, // This key will be used ~30% of the time
			},
		},
	}}

	// Create the HasteKit client
	client := hastekit.NewLLMClient(providerConfigs)
}
```