> ## Documentation Index
> Fetch the complete documentation index at: https://dify-6c0370d8-docs-new-agent-experience.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# App

> Call the Chat, Workflow, and Completion interfaces of Dify Apps from your plugin

A plugin can reverse invoke an App within Dify to access its data, with both streaming and non-streaming calls. If you are unfamiliar with the basics of reverse invocation, first read [Reverse Invocation of Dify Services](/en/develop-plugin/features-and-specs/advanced-development/reverse-invocation).

**Interface Types**:

* **Chat Interface**: `Chatbot`, `Agent`, and `Chatflow` applications are all chat-based and share the same input and output parameter types, so they share this interface.
* **Workflow Interface**: Used by Workflow applications.
* **Completion Interface**: Used by Completion (text generation) applications.

Plugins can only access Apps within the Workspace where the plugin resides.

## Call the Chat Interface

### Entry Point

```python theme={null}
    self.session.app.chat
```

### Interface Specification

```python theme={null}
    def invoke(
        self,
        app_id: str,
        inputs: dict,
        response_mode: Literal["streaming", "blocking"],
        conversation_id: str,
        files: list,
    ) -> Generator[dict, None, None] | dict:
        pass
```

When `response_mode` is `streaming`, this interface returns `Generator[dict]`; otherwise it returns `dict`. For the specific interface fields, see the return results of `ServiceApi`.

### Use Case

This example calls a Chat type App within an `Endpoint` and returns the result directly:

```python theme={null}
import json
from typing import Mapping
from werkzeug import Request, Response
from dify_plugin import Endpoint

class Duck(Endpoint):
    def _invoke(self, r: Request, values: Mapping, settings: Mapping) -> Response:
        """
        Invokes the endpoint with the given request.
        """
        app_id = values["app_id"]

        def generator():
            response = self.session.app.chat.invoke(
                app_id=app_id,
                inputs={},
                response_mode="streaming",
                conversation_id="some-conversation-id",
                files=[],
            )

            for data in response:
                yield f"{json.dumps(data)} <br>"

        return Response(generator(), status=200, content_type="text/html")
```

## Call the Workflow Interface

### Entry Point

```python theme={null}
    self.session.app.workflow
```

### Interface Specification

```python theme={null}
    def invoke(
        self,
        app_id: str,
        inputs: dict,
        response_mode: Literal["streaming", "blocking"],
        files: list,
    ) -> Generator[dict, None, None] | dict:
        pass
```

## Call the Completion Interface

### Entry Point

```python theme={null}
    self.session.app.completion
```

### Interface Specification

```python theme={null}
    def invoke(
        self,
        app_id: str,
        inputs: dict,
        response_mode: Literal["streaming", "blocking"],
        files: list,
    ) -> Generator[dict, None, None] | dict:
        pass
```

## Related Resources

* [Reverse Invocation of Dify Services](/en/develop-plugin/features-and-specs/advanced-development/reverse-invocation) - Understand the fundamental concepts of reverse invocation
* [Reverse Invocation Model](/en/develop-plugin/features-and-specs/advanced-development/reverse-invocation-model) - Learn how to call model capabilities within the platform
* [Reverse Invocation Tool](/en/develop-plugin/features-and-specs/advanced-development/reverse-invocation-tool) - Learn how to call other plugins
* [Develop a Slack Bot Plugin](/en/develop-plugin/dev-guides-and-walkthroughs/develop-a-slack-bot-plugin) - A practical application case using reverse invocation
* [Develop Extension Plugins](/en/develop-plugin/dev-guides-and-walkthroughs/endpoint) - Learn how to develop extension plugins