Invoke no-code agents via the API

The Applications API allows you to turn deployed no-code agents into microservices, which can also be used as tools in tool calling. Business users can define inputs, prompts, and outputs, and developers can then add them to other applications, UIs, or services.

This guide shows how to use the /applications endpoint to generate content from no-code agents.

If you do not have a deployed no-code agent, follow the guides to build an agent with text generation or research capabilities in AI Studio.

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Endpoint overview

URL: POST https://api.writer.com/v1/applications/{application_id}

curl 'https://api.writer.com/v1/applications/<application-id>' \
-X POST \
-H 'Content-Type: application/json' \
-H "Authorization: Bearer $WRITER_API_KEY" \
--data-raw '{
  "inputs": [
    {
      "id": "Product description",
      "value": [
        "Terra running shoe"
      ]
    }
  ]
}'

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Path parameters

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Request body

Below are the required and commonly used optional parameters for the /applications endpoint.

{
  "inputs": [
    {
      "id": "string",
      "value": ["string"]
    }
  ]
}

See the applications endpoint reference for more information on the request body and the additional parameters you can use to control the agent.

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Response format

The response format depends on the agent capabilities and whether you set the stream parameter to true or false. Only agents with research support streaming responses at this time.

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Non-streaming response

If you set the stream parameter to false, the response is delivered as a JSON object with the following parameters:

{
  "title": null,
  "suggestion": "The Terra running shoe combines lightweight materials with advanced cushioning technology to deliver exceptional comfort and performance for every stride."
}

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Streaming response

If you set the stream parameter to true, the response is delivered as server-sent events. The event contains several parameters.

The content of the chunk is in the delta field. You can also use the stages field to get the stages of the research assistant application call, such as “Planning the research” or “Researching and organizing findings.”

Below are the important parameters for extracting the output of the application call.

data: {'delta': {'title': None,
  'content': None,
  'stages': [{'id': 'a5d81590-0120-4404-948b-8075e3610f51',
    'content': 'Initiating a research assistant: 🚗 Automotive assistant',
    'sources': None}]}}

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Example: Text generation

Agents used for text generation generate content based on the inputs provided to a specific no-code agent created in AI Studio. This is a great way to enable business users to control prompts and outputs while still allowing developers to add them to other applications, UIs, or services.

To invoke text generation, you need to provide the application ID and the required inputs to the agent. Inputs are defined in the agent within AI Studio.

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Get the text generation inputs

To see the required inputs for the agent, you can view the agent in AI Studio, or you can use the Get application endpoint to get the agent details, including the inputs.

The example below shows how to use the Get application endpoint to get the list of required inputs with their name and types.

curl --location --request GET https://api.writer.com/v1/applications/<application-id> \
 --header "Authorization: Bearer $WRITER_API_KEY"

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Format the request body with the application inputs

The inputs parameter is an array of objects, each containing an id and value field. The id field is the name of the input field, and the value field is the value of the input field.

{
  "inputs": [
    {
      "id": "Text input name",
      "value": ["Input value 1"]
    },
    {
      "id": "File input name",
      "value": ["1234-fileid-1234"]
    }
  ]
}

If the input field is a file, the value should be the file_id from an uploaded file.

Your request body should be formatted as a JSON object with values for each input.

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Generate content from the agent

Once you’ve formatted the request body with the agent inputs, you can invoke the agent using the Generate content endpoint.

The examples below demonstrate calling an agent with text generation capabilities. The agent takes two text inputs: Product description and Target audience.

curl --location --request POST 'https://api.writer.com/v1/applications/{application_id}' \
--header "Authorization: Bearer $WRITER_API_KEY" \
--data-raw '{
  "inputs": [
    {
      "id": "Product description",
      "value": ["Terra running shoe"]
    },
    {
      "id": "Target audience",
      "value": ["Runners"]
    }
  ]
}'

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Example: Research assistant

Agents with research capabilities output a final report after performing research in stages. Because of this, they support streaming responses.

These agents take an array of inputs that contain a single item, formatted as a JSON object with id and value parameters. It also takes a stream parameter that is set to false by default.

The examples below demonstrate calling an agent to research hotels in San Francisco. The application streams the output as it is generated.

curl --location --request POST 'https://api.writer.com/v1/applications/{application_id}' \
--header "Authorization: Bearer $WRITER_API_KEY" \
--data-raw '{
  "inputs": [
    {
      "id": "query", 
      "value": ["Provide a list of three hotels in San Francisco near Union Square within the price range of $100 to $200 per night"]
    }
  ],
  "stream": true
}'

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Next steps

Now that you’ve invoked a no-code agent via the API, learn other ways you can use no-code agents via the API:

• Run no-code agents asynchronously
• Use no-code agents in tool calling