node-red-contrib-claude 1.1.0
A Node-RED node to interact with the Anthropic Claude API
node-red-contrib-claude
A Node-RED node for interacting with the Anthropic Claude API.
Requirements
- Node-RED >= 2.0.0
- Node.js >= 14.0.0
- An Anthropic API key
Installation
From npm (once published):
cd ~/.node-red
npm install node-red-contrib-claude
From source (local development):
cd ~/.node-red
npm install /path/to/node-red-contrib-claude
Then restart Node-RED. The claude node will appear in the AI category of the palette.
Configuration
Open the node's properties panel and enter your Anthropic API key. All other fields are optional defaults that can be overridden per-message at runtime.
| Property | Default | Description |
|---|---|---|
| API Key | — | Your Anthropic API key (sk-ant-…) |
| Model | claude-sonnet-4-6 |
Claude model ID |
| Max Tokens | 1024 |
Maximum tokens to generate |
| System Prompt | (none) | System prompt sent with every message |
| Temperature | (model default) | Sampling temperature (0–1) |
| Top P | (model default) | Nucleus sampling (0–1) |
| Top K | (model default) | Top-k sampling (integer ≥ 1) |
Usage
Input
| Property | Type | Required | Description |
|---|---|---|---|
msg.payload |
string | Yes | The prompt / query text sent to Claude |
msg.model |
string | No | Override the model for this message |
msg.maxTokens |
number | No | Override max tokens for this message |
msg.systemPrompt |
string | No | Override the system prompt for this message |
msg.temperature |
number | No | Override temperature for this message |
msg.topP |
number | No | Override top-p for this message |
msg.topK |
number | No | Override top-k for this message |
Non-string payloads are automatically serialized to JSON before being sent.
Output (success)
| Property | Type | Description |
|---|---|---|
msg.payload |
string | The text response from Claude |
msg.claudeRaw |
object | Full API response (usage stats, stop reason, etc.) |
Output (API error)
| Property | Type | Description |
|---|---|---|
msg.payload |
null | |
msg.claudeError |
object | { status: <HTTP code>, message: "" } |
The node still forwards the message downstream on API errors so flows can handle them explicitly.
Node status indicators
| Color | Text | Meaning |
|---|---|---|
| Blue | Thinking… | Waiting for API response |
| Green | OK | Request succeeded |
| Red | error <code> |
API returned a non-200 status |
| Red | missing payload | msg.payload was empty |
| Red | no API key | API key not configured |
| Red | request failed | Network/connection error |
Example Flows
Import examples/flows.json via Menu → Import in the Node-RED editor. It contains four ready-to-use flows:
| Tab | What it shows |
|---|---|
| 1 - Basic Q&A | Inject a question → claude → debug. The simplest possible usage. |
| 2 - System Prompt | System prompt set in the node config so Claude always responds as a Python tutor. |
| 3 - Runtime Overrides | A function node sets msg.model, msg.systemPrompt, and msg.maxTokens before calling the claude node, overriding the node config per-message. |
| 4 - Error Handling | A switch node branches on msg.claudeError (null = success, non-null = API error) so failures are handled explicitly. |
After importing, open each claude node and enter your Anthropic API key before deploying.
Project Structure
claude.js — Node-RED runtime (registers node type, handles API calls)
claude.html — Node-RED editor UI and help panel
package.json — Package manifest and node-red node registration
License
MIT © Paramesh Gunasekaran
