AI_InvalidPromptError

This error occurs when the prompt provided is invalid.

Potential Causes

System Messages in prompt or messages

AI SDK functions reject system messages in the prompt or messages fields to reduce the risk of prompt injection. Pass system instructions with the instructions option instead:

import { generateText } from 'ai';

const result = await generateText({
  // ...
  instructions: 'You are a helpful assistant.',
  messages,
});

If the system messages come from a trusted source, you can allow them with allowSystemInMessages: true.

Empty Messages

The messages array (or a prompt given as an array) must contain at least one message.

Provider-Specific Prompt Requirements

Some providers throw this error when a prompt can't be expressed for their API, for example when an assistant prefix message isn't the final message, or when a part combines options the provider doesn't support. The error message describes the provider requirement that wasn't met.

Properties

• prompt: The invalid prompt value
• message: The error message (required in constructor)
• cause: The cause of the error (optional)

Checking for this Error

You can check if an error is an instance of AI_InvalidPromptError using:

import { InvalidPromptError } from 'ai';

if (InvalidPromptError.isInstance(error)) {
  // Handle the error
}