The Large Language Model (LLM) node enables calling large language models within workflows. By configuring prompts and model parameters, it generates text responses based on input data. It supports both single-item processing and batch processing modes—ideal for content generation, multi-turn conversations, and similar use cases.
The LLM node supports two execution modes:
Additional parameters required in Batch Processing Mode:
Select a large language model (e.g., Qwen series) from the model dropdown. If your target model isn’t listed, click More Models to open the model selection dialog and search for and select it.
Click the configuration icon (⚙️) next to the model selector. After enabling the parameter panel, configure the following:
Inserting Variables: In the prompt editor, type
Enabled by default. When enabled, the model retains conversation history—supporting multi-turn dialogue scenarios.
Single-Item Processing Mode:
Batch Processing Mode:
Disabled by default. Automatically retries the node upon timeout or error. When disabled, failures cause immediate workflow errors.
Disabled by default. Defines behavior when the node fails.
Adding the Node
Method 1: Add via the Plus (+) Button
- Click the plus (+) button at the end of any existing node on the canvas.
- Select the LLM node from the pop-up node list.
- The node is automatically added to the canvas and connected to the upstream node.
Method 2: Drag-and-Drop
- Locate the LLM node in the left-hand node library.
- Drag it onto the desired position on the canvas.
- Manually connect it to an upstream node (drag the output port of the upstream node to the input port of the LLM node).
Core Configuration
Processing Mode
The LLM node supports two execution modes:
| Mode | Description |
|---|---|
| Single-Item Processing Mode | The node runs once, processes a single input, and returns a single result. Supports memory, failure retries, and exception handling. |
| Batch Processing Mode | The node runs multiple times, sequentially processing each element in an array as defined by the batch variable. Does not support memory, failure retries, or exception handling. |
| Parameter | Range | Default | Description |
|---|---|---|---|
| Max Batch Count | 1–100 | 50 | Maximum number of batch executions. Actual count equals the smaller of the input array length and this limit. |
| Parallel Execution Count | 1–10 | 5 | Number of concurrent batch executions. Setting to 1 enforces serial execution. |
| Batch Variable | — | — | Configures the variable to be batch-processed—including its name, reference method, and value. |
Model Configuration
Model Selection
Select a large language model (e.g., Qwen series) from the model dropdown. If your target model isn’t listed, click More Models to open the model selection dialog and search for and select it.
Model Parameters
Click the configuration icon (⚙️) next to the model selector. After enabling the parameter panel, configure the following:
| Parameter | Default | Description |
|---|---|---|
| Max Output Length | 1024 | Maximum number of tokens in the model’s output. |
| top_p | 0.80 | Controls output diversity—higher values yield more varied outputs. |
| temperature | 0.70 | Controls output randomness—higher values yield more stochastic outputs. |
| enable_thinking | Enabled | Enables deep reasoning mode; outputs step-by-step reasoning traces. |
| thinking_budget | 4000 | Maximum number of tokens allowed for reasoning chain output (in thinking mode). |
| result_format | message | Format of returned result. |
| enable_search | Disabled | Enables web search capability. |
Prompt Configuration
| Prompt Type | Description |
|---|---|
| System Prompt | Defines the model’s role and behavioral guidelines. Example: “You are a professional Q&A assistant. Your answers must be professional, concise, and directly address the question. If you don’t know the answer, respond with ‘I don’t know.’” |
| User Prompt | Contains user-provided input passed to the model. Supports variable references via ${node_name/variable_name}. Example: “Answer the user’s question: ${Start/query}” (where ${Start/query} references the built-in query variable from the Start node). |
/ to trigger the variable selector popup. Choose output variables from upstream nodes. Syntax: ${node_name/variable_name}, e.g., ${Start/query}.
Memory
Enabled by default. When enabled, the model retains conversation history—supporting multi-turn dialogue scenarios.
| Cache Type | Description |
|---|---|
| Node-Level Cache | The model remembers only the dialogue history within this node. Configure Memory Rounds (1–50, default: 3), where one round = one input + one output. |
| Custom Cache | The model retains global context. Requires selecting a context variable (e.g., built-in historyList). |
Output Variables
Single-Item Processing Mode:
| Output Variable | Type | Description |
|---|---|---|
result | String | Text content generated by the model. |
reasoningContent | String | Reasoning trace (output only when thinking mode is enabled). |
| Output Variable | Type | Description |
|---|---|---|
result | Array<String> | Array containing results from each batch item. |
reasoningContent | Array<String> | Array containing reasoning traces per batch item. |
Retry on Failure
Disabled by default. Automatically retries the node upon timeout or error. When disabled, failures cause immediate workflow errors.
| Parameter | Range | Default | Description |
|---|---|---|---|
| Max Retry Count | 1–10 | 3 | Maximum number of retries on request failure. |
| Retry Interval | 300–10,000 ms | 500 | Delay between consecutive retries. |
Exception Handling
Disabled by default. Defines behavior when the node fails.
| Handling Strategy | Description | Default |
|---|---|---|
| Return preset default values on failure (requires per-output-variable defaults). | Routes execution to an exception branch, allowing downstream nodes to handle the error case. | Enabled |
Common Integration Patterns
| Paired Node | Typical Use Case |
|---|---|
| Knowledge Base Node → LLM Node | Retrieve from knowledge base, then pass results to the LLM node for RAG-enhanced Q&A. |
| LLM Node → Conditional Node | Branch logic based on the result output—for example, routing to different business paths. |
| LLM Node → Workflow Output Node | Emit LLM-generated output mid-workflow to enable streaming-style responses. |