> ## Documentation Index
> Fetch the complete documentation index at: https://docs.t3planet.de/en/latest/llms.txt
> Use this file to discover all available pages before exploring further.

# Feature Provider Overrides

> Feature Provider Overrides for EXT:ns_t3af (T3AF).

Feature provider overrides allow an extension to offer a dedicated default AI provider for a specific feature while still using T3AF’s shared provider registry.

Use this when one feature should use a different model or provider than the global default. Examples include SEO generation, page generation, content generation, and LLM-based translation.

## How it works

T3AF owns the provider rows. The child extension exposes feature-specific provider fields in T3AF > AI Features. At runtime, the feature resolves the provider in this order:

1. Provider selected in the runtime modal, if the request includes one.
2. Feature default saved in AI Features.
3. Global default provider fallback.

## Supported implementation hook

Child extensions register provider dropdowns by implementing:

`NITSAN\NsT3AF\Contract\FeatureProviderFormOptionsInterface`

Register the service with:

`t3af.feature_provider_form_options`

T3AF uses the registered service to render provider options in the feature settings drawer.

## Known feature fields

AI Assistant uses feature-specific default provider fields such as:

* `defaultProviderForSeo`
* `defaultProviderForPages`
* `defaultProviderForContent`
* `defaultProviderForTranslation`
* `defaultModel`
* `defaultEmbeddingsModel`

Each dropdown lists enabled providers from **AI Providers**. The **Default (inherit global provider)** option keeps the feature on the global provider path.

## Translation note

`defaultModelForTranslation` still selects the translation backend, such as DeepL, Google, or an AI-based path. `defaultProviderForTranslation` applies only to LLM completion paths that use the T3AF completion gateway.

## Configuration workflow

1. Register a feature card with [Custom AI Features](/en/latest/en/latest/ExtNsT3AF/DeveloperGuide/CustomFeatureCards/Index).
2. Add the provider field to that feature’s settings schema.
3. Implement `FeatureProviderFormOptionsInterface`.
4. Tag the service with `t3af.feature_provider_form_options`.
5. Flush caches.
6. Open T3AF > AI Features and verify the provider dropdown.
7. Save a default provider and test the runtime feature.

## Best practices

* Keep provider field names stable.
* Always include an inherit/default option.
* Use the same label, **AI Provider**, when the same choice appears in runtime modals.
* Resolve providers through the feature runtime path instead of reading provider rows directly.
* Do not hardcode provider IDs in feature logic.

## Verification

1. Open T3AF > AI Providers and confirm at least one provider is enabled.
2. Open T3AF > AI Features.
3. Open the feature settings drawer.
4. Confirm the provider dropdown contains enabled providers.
5. Save a feature default.
6. Open the feature runtime modal and confirm the saved provider is preselected.

## Troubleshooting

**Dropdown is missing**

* Confirm the form-options service implements the correct interface.
* Confirm the service is tagged with `t3af.feature_provider_form_options`.
* Confirm the related feature card and scope provider are active.

**Runtime uses the wrong provider**

* Confirm the request field name matches the saved setting.
* Confirm the feature handles `default` or empty values as fallback.
* Confirm the saved provider row still exists and is enabled.

## Related documentation

* [Custom AI Features](/en/latest/en/latest/ExtNsT3AF/DeveloperGuide/CustomFeatureCards/Index)
* [Extension Integration](/en/latest/en/latest/ExtNsT3AF/DeveloperGuide/ExtensionIntegration/Index)
* [AI Providers](/en/latest/en/latest/ExtNsT3AF/Configuration/AIProviders/Index)
* [AI Features](/en/latest/en/latest/ExtNsT3AF/Configuration/AIFeatures/Index)