microsoft--promptflow/docs/reference/flow-yaml-schema-reference.md

Flow YAML Schema

:::{admonition} Experimental feature This is an experimental feature, and may change at any time. Learn more. :::

The source JSON schema can be found at Flow.schema.json

YAML syntax

Key	Type	Description
$schema	string	The YAML schema. If you use the prompt flow VS Code extension to author the YAML file, including $schema at the top of your file enables you to invoke schema and resource completions.
inputs	object	Dictionary of flow inputs. The key is a name for the input within the context of the flow and the value is the flow input definition.
inputs.<input_name>	object	The flow input definition. See Flow input for the set of configurable properties.
outputs	object	Dictionary of flow outputs. The key is a name for the output within the context of the flow and the value is the flow output definition.
outputs.<output_name>	object	The component output definition. See Flow output for the set of configurable properties.
nodes	array	Sets of dictionary of individual nodes to run as steps within the flow. Node can use built-in tool or third-party tool. See Nodes for more information.
node_variants	object	Dictionary of nodes with variants. The key is the node name and value contains variants definition and default_variant_id. See Node variants for more information.
environment	object	The environment to use for the flow. The key can be image or python_requirements_txt and the value can be either a image or a python requirements text file.
environment_variables	object/string	Environment variables to set by specifying a property path and value. Example: {"key1"="${my_connection.api_key}"}. The value reference to connection keys will be resolved to the actual value, and all environment variables specified will be set into os.environ.
additional_includes	array	Additional includes is a list of files that can be shared among flows. Users can specify additional files and folders used by flow, and prompt flow will help copy them all to the snapshot during flow creation.

Flow input

Key	Type	Description	Allowed values
type	string	The type of flow input.	int, double, bool, string, list, object, image
description	string	Description of the input.
default	int, double, bool, string, list, object, image	The default value for the input.
is_chat_input	boolean	Whether the input is the chat flow input.
is_chat_history	boolean	Whether the input is the chat history for chat flow.

Flow output

Key	Type	Description	Allowed values
type	string	The type of flow output.	int, double, bool, string, list, object
description	string	Description of the output.
reference	string	A reference to the node output, e.g. ${<node_name>.output.<node_output_name>}
is_chat_output	boolean	Whether the output is the chat flow output.

Nodes

Nodes is a set of node which is a dictionary with following fields. Below, we only show the common fields of a single node using built-in tool.

Key	Type	Description	Allowed values
name	string	The name of the node.
type	string	The type of the node.	Type of built-in tool like Python, Prompt, LLM and third-party tool like Vector Search, etc.
inputs	object	Dictionary of node inputs. The key is the input name and the value can be primitive value or a reference to the flow input or the node output, e.g. ${inputs.<flow_input_name>}, ${<node_name>.output} or ${<node_name>.output.<node_output_name>}
source	object	Dictionary of tool source used by the node. The key contains type, path and tool. The type can be code, package and package_with_prompt.
provider	string	It indicates the provider of the tool. Used when the type is LLM.	AzureOpenAI or OpenAI
connection	string	The connection name which has been created before. Used when the type is LLM.
api	string	The api name of the provider. Used when the type is LLM.
module	string	The module name of the tool using by the node. Used when the type is LLM.
use_variants	bool	Whether the node has variants.

Node variants

Node variants is a dictionary containing variants definition for nodes with variants with their respective node names as dictionary keys. Below, we explore the variants for a single node.

Key	Type	Description	Allowed values
<node_name>	string	The name of the node.
default_variant_id	string	Default variant id.
variants	object	This dictionary contains all node variations, with the variant id serving as the key and a node definition dictionary as the corresponding value. Within the node definition dictionary, the key labeled 'node' should contain a variant definition similar to Nodes, excluding the 'name' field.

Examples

Flow examples are available in the GitHub repository.

• basic
• web-classification
• chat-basic
• chat-with-pdf
• eval-basic