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Updated in 2026.20.0
LLM Prompt Node

Description

As of Cognigy 2026.18.0, the following parameters are deprecated:
  • Sampling Method
  • Temperature
  • Top Percentage
  • Maximal Tokens
  • Frequency Penalty
  • Presence Penalty
  • Use Stops
  • Stops
  • Seed
The removal is planned for April 2027. For models that don’t support these parameters, activate the Ignore deprecated parameters toggle to exclude them from the request to the LLM provider. Otherwise, the request to the LLM provider might fail. If you plan to use these parameters, migrate them to the Custom Options section and activate the Ignore deprecated parameters toggle. Otherwise, Custom Options might not override them for every provider and model combination.For example, OpenAI models such as gpt-5, gpt-5.1, and gpt-5.2 don’t support these parameters. Similar models from other LLM providers might also not support these parameters. Check your LLM provider’s documentation for model-specific support.
The LLM Prompt Node lets you configure LLMs for your AI Agent and their system prompt to generate both text and structured content. With this Node, you can also: Additionally, you can refer to your AI Agent configuration using the Load AI Agent Node.
In comparison to the AI Agent Node, the LLM Prompt Node doesn’t include the AI Agent persona. If you want to have centralized control over the personality, tone, and voice of different AI Agents, use different AI Agent Nodes with the same persona.

Prerequisites

Limitations

  • The Description and Enum fields in the Parameters section of an AI Agent tool don’t support CognigyScript.

Parameters

Parent Node

The preselected Default model is the model configured in the Generative AI Settings section of the Project settings.To use another model in this Node, select a different one from the list or override the default model with the Custom Options parameter.
The system prompt is the message sent to the LLM to guide its responses. This parameter supports CognigyScript, allowing dynamic content and logic in the prompt. This prompt can work either as the input for completion tasks or as the system message in chat-based interactions, setting context and behavior for the AI Agent.Additionally, you can inject the recent conversation into the System Prompt field by using these tags:
  • @cognigyRecentConversation — injects a string that contains up to the 10 most recent conversation turns, for example:
  • @cognigyRecentUserInputs — injects a string that contains up to the 10 most recent user outputs, for example:
To access only the last user input, enter {{ci.text}} or the Text token in the System Prompt field.When you use tags, add a line break before and after the tag, for example:
Both tags include an optional limit parameter, which is appended to the tag, for example:
Streaming ResultsWhen you select Stream to Output, the LLM generates tokens and returns them one by one to Cognigy to ensure low-latency responses. Cognigy monitors delimiter tokens (Stream Buffer Flush Tokens), which serve as markers indicating when to output the token buffer. These tokens can be ., !, ?, or any other symbols that act as delimiters for complete logical statements. When Cognigy detects one of these tokens, it promptly flushes the token buffer into the voice or chat output.The preconfigured overrides are listed in the table.
The process of setting up a tool is the same as for the AI Agent Node. See the example in the AI Agent Tool Settings section.
These options let you use parameters that aren’t included in the LLM Prompt Node or override existing configurations.Forcing Model VersionsYou can force the LLM Prompt Node to use a specific model version by including it in the Custom Options. This means that the LLM Prompt Node uses the specified version of the language model instead of the default or any other available versions. This gives you more control over the behavior of the LLM Prompt Node, ensuring it uses a specific model version for generating prompts or responses.You can use any models from LLM providers supported by Cognigy, including those not yet directly integrated. However, you can only replace a model with another from the same provider.Consider an example with Anthropic as the LLM provider:You can force the LLM Prompt Node to use the model version claude-opus-4-8-20260101, despite the LLM resource defaulting to the claude-sonnet-4-6 model:
  1. Create an Anthropic LLM resource for Claude, for example, claude-sonnet-4-6.
  2. Create a Flow and add an LLM Prompt Node to it.
  3. In the LLM Prompt Node, select the model claude-sonnet-4-6 from the Large Language Model list.
  4. In the Custom Options field, add { "model": "claude-opus-4-8-20260101" } to force the use of the claude-opus-4-8-20260101 model.
  5. Click Save Node.
The LLM Prompt Node then uses the claude-opus-4-8-20260101 model.For more information on supported models, see:Forcing JSON Output on Amazon Bedrock and AnthropicFor Amazon Bedrock and Anthropic models, add the output_config parameter to the Custom Options field to force the model to return a specific JSON response.For example, to force the model to return JSON matching a specific schema:
With this configuration, a prompt such as “What is 1+1?” returns a response like {"answer": 2} instead of plain text.
These settings provide two approaches for debug logging:
  • Debug messages in the Interaction Panel — appear only during testing with the Interaction Panel and aren’t intended for production.
  • Webhook request logs — can be used in production to inspect LLM requests and completions.
You can use both approaches at the same time.

Child Nodes

Tool

Tools are child Nodes of AI Agent Nodes. They define the actions the AI Agent can take. If an AI Agent wants to execute the tool, the branch below the child Node is executed.
To better guide your AI Agent, use a Resolve Tool Action Node at the end of a tool branch to return to the AI Agent after tool execution.
Clicking the Tool Node lets you define a tool, set its parameters, and enable debugging by turning on detailed messages about the tool’s execution.
Configure the parameters that the AI Agent collects before the tool is called. You can switch between the graphical and JSON editors. When using the JSON editor, follow the JSON Schema specification.

MCP Tool

An MCP Tool Node is a type of Tool Node that connects to a remote MCP server to load tools that the AI Agent can execute. If an AI Agent wants to execute one of the loaded tools, the branch below the MCP Tool Node is triggered. In the MCP Tool Node, you can define the connection, filter loaded tools, and turn on detailed messages about the tool’s execution for debugging.

Call MCP Tool

In the Flow editor, when you add an MCP Tool Node, a Call MCP Tool Node is automatically created below it. These two Nodes work together to define and execute the chosen tool. The Call MCP Tool Node sets the actual execution point of the chosen tool. This way, you can verify or modify the tool call arguments in the input.aiAgent.toolArgs object, or add a Say Node before the tool call. When the Call MCP Tool Node is executed, the tool call is sent to the remote MCP server, where the tool is executed remotely with any arguments set by the AI Agent. To return the tool result to the AI Agent, enable Resolve Immediately to send the full result from the remote MCP server to the AI Agent. As an alternative, use a Resolve Tool Action Node to return a specific result to the AI Agent.

A2A Agent

A2A Agent Nodes are child Nodes of AI Agent Nodes. An A2A Agent Node allows the AI Agent Node to connect to a remote A2A agent and use it as a single tool. The remote A2A agent can advertise multiple skills, but the AI Agent Node always sees them as a single tool. The skills are summarized in the tool description to help the AI Agent Node decide when to use it. In the A2A Agent Node, configure the A2A agent connection, authentication, skill filtering, and debugging options.
The A2A Agent Node covers the following use cases:
Delegate a subtask to a specialist A2A agent, such as an SAP or IT operations agent. The AI Agent Node remains in control of the conversation.
Connect to an A2A agent operated by a partner organization for tasks such as booking, procurement, or support.

Call A2A Agent

Cognigy.AI automatically creates a Call A2A Agent Node below an A2A Agent Node. The A2A Agent Node defines the A2A agent connection, while the Call A2A Agent Node executes the call. Use the Call A2A Agent Node to modify or inspect the message before it is sent, add a Say Node, and configure how the result is returned to the AI Agent Node. When the Call A2A Agent Node runs, it sends the message to the remote A2A agent and handles the response according to the configured execution mode. The Agent Card determines the supported A2A protocol version, so no version configuration is required. If the remote A2A agent supports streaming, the Node consumes the response as it arrives. Otherwise, it sends a request. In Non-blocking mode, the Node polls the resulting task until it completes or the task times out. To return the result to the AI Agent Node, enable Resolve Immediately. Alternatively, use a Resolve Tool Action Node to return a specific result. If the remote A2A agent requires additional input or authentication, the AI Agent Node calls the tool again. Max autonomous calls per turn limits how often this can happen.

Knowledge Tool

The Knowledge Tool Node is a child Node of the AI Agent Node. It lets the AI Agent directly access Knowledge Stores to provide context-aware responses. In the Knowledge Tool Node, you can select the Knowledge Store to search, Source Tags to refine the search, and output detailed debug messages about the tool’s execution.

Send Email Tool

The Send Email tool lets your AI Agent send emails directly to users. The Send Email tool uses the same configuration and restrictions as the Email Notification Node but adds more flexibility. While the Email Notification Node sends emails at a fixed step in a Flow, the Send Email tool allows the AI Agent to send emails dynamically, based on user input, conversation context, or instructions. This tool makes automation more flexible and minimizes extra Flow steps.

Handover to AI Agent Tool

The Handover to AI Agent tool lets you transfer a conversation to another AI Agent in the same or a different Flow. This approach ensures the conversation keeps its context, different AI Agents can handle specific tasks, and multi-step conversations run smoothly across Flows.

Handover to Human Agent Tool

The Handover to Human Agent tool lets you transfer a conversation to a human agent through handover providers. This tool lets your AI Agents refer complex tasks to a human agent if they can’t address the user’s request.

Execute Workflow Tool

The Execute Workflow tool lets the AI Agent execute another Flow. After the target Flow executes, the conversation returns to the AI Agent. The target Flow inherits the Context object from the AI Agent. If the target Flow changes the Context object, these changes are also available to the AI Agent.

Examples

Tool

In this example, the unlock_account tool unlocks a user account by providing the email and specifying the reason for the unlocking. Parameter configuration in JSON:
where:
  • type — the type for a tool parameter schema, which must always be object.
  • properties — defines the parameters for the tool configuration:
    • email — a required tool parameter for unlocking the account.
      • type — defines the data type for the tool parameter.
      • description — a brief explanation of what the property represents.
  • required — lists email as a required parameter, ensuring that this value is always provided when the tool is called.
  • additionalProperties — ensures that the input contains only the email tool parameter, and no others are allowed.

MCP Tool and Call MCP Tool

Use Zapier’s Remote MCP server

You can create a custom MCP server with personalized tools by using one of the provided SDKs. For a quicker setup, you can use a third-party provider. For example, Zapier allows you to configure your MCP server, which can be connected to multiple application APIs. To use Zapier as a remote MCP server, follow these steps:
  1. Log in to your Zapier account, go to the MCP settings page, and configure your MCP server.
  2. Copy the SSE URL and paste it into the MCP Server SSE URL field of your MCP Tool Node.
  3. In the Zapier MCP settings, create an action to connect to various APIs. For example, you can create a Zapier action to automatically generate a Google Doc.
Once the setup is complete, the configured MCP Actions will be loaded when the AI Agent is executed. You will see the following debug message in the Interaction Panel, indicating the result of the tool call after a successful execution:

Knowledge Tool

In this example, you have two Knowledge tools to search two different Knowledge Stores. Each Knowledge Store refers to a different product category, in this example, appliances and furniture. To guide the AI Agent to use the correct Knowledge tool, enter a clear tool ID and description:
  • Knowledge Tool 1:
    • Tool ID: search_appliances
    • Description: Find the answer to prompts or questions about appliances by searching the attached data sources. Use this tool when a customer asks about appliance items such as washing machines, dryers, and other household appliances. Focus exclusively on a knowledge search and does not execute tasks like small talk, calculations, or script running.
  • Knowledge Tool 2:
    • Tool ID: search_furniture
    • Description: Find the answer to prompts or questions about furniture by searching the attached data sources. Use this tool when a customer asks about furniture items such as sofas, tables, and other items. Focus exclusively on a knowledge search and does not execute tasks like small talk, calculations, or script running.

More Information


1: Note that not all LLMs support streaming.
Last modified on October 1, 2026