Manifest

Let's go through an example of the typical starthub.json file.

{
  "name": "get-weather-by-location-name",
  "description": "Get weather by location name",
  "version": "0.0.1",
  "kind": "composition",
  "manifest_version": 1,
  "repository": "github.com/tgirotto/get-weather-by-location-name",
  "license": "MIT",
  "inputs": [
    {
      "name": "weather_config",
      "type": "WeatherConfig",
    }
  ],
  "steps": {
    "get_coordinates": {
      "uses": "tgirotto/openweather-coordinates-by-location-name:0.0.1",
      "inputs": [
        {
          "location_name": "{{inputs[0].location_name}}",
          "open_weather_api_key": "{{inputs[0].open_weather_api_key}}"
        }
      ]
    },
    "get_weather": {
      "uses": "tgirotto/openweather-current-weather:0.0.1",
      "inputs": [
        {
          "lat": "{{steps.get_coordinates.outputs[0].lat}}",
          "lon": "{{steps.get_coordinates.outputs[0].lon}}",
          "open_weather_api_key": "{{inputs[0].open_weather_api_key}}"
        }
      ]
    }
  },
  "outputs": [
    {
      "name": "response",
      "description": "Simplified weather information for the location",
      "type": "CustomWeatherResponse",
      "value": {
        "location_name": "{{inputs[0].location_name}}",
        "weather": "{{steps.get_weather.outputs[0].weather[0].description}}"
      }
    }
  ],
  "types": {
    "WeatherConfig": {
      "location_name": "string",
      "open_weather_api_key": "string"
    },
    "CustomWeatherResponse": {
      "location_name": "string",
      "weather": "string"
    }
  }
}

Name

Name of the action.

Description

Description of the action.

Version

Version of the action. Follows semantic versioning (e.g., "0.0.1", "1.2.3").

Kind

The type of action. Can be one of:

• "docker" - A Docker-based action
• "wasm" - A WebAssembly-based action
• "composition" - A composite action composed of other actions

Manifest Version

Version of the manifest schema being used. Currently 1.

Repository

The repository URL where the action is hosted (e.g., "github.com/tgirotto/get-weather-by-location-name").

License

The license under which the action is distributed (e.g., "MIT", "Apache-2.0", "GPL-3.0").

Inputs

Array of input parameters that the action accepts. Each input has:

• name - The name of the input parameter
• type - The type of the input (primitive or custom type)
• required - Whether the input is required (boolean)

Steps

For composition actions, defines the steps that make up the action. Each step:

• uses - Reference to another action (format: "owner/action-name:version")
• inputs - Inputs passed to the step, which can reference parent inputs or outputs from previous steps using template syntax

Outputs

Array of output values that the action produces. Each output has:

• name - The name of the output
• description - Description of what the output contains
• type - The type of the output (primitive or custom type)
• value - The value expression, which can reference inputs or step outputs using template syntax

Types

Custom type definitions used in inputs and outputs. Defines the structure of complex types as key-value pairs where keys are property names and values are their types.