System prompt issue with Anthropic

[nabeelraza-7]

I'm trying to use the createAnthropic function with a different provider by aimlapi.com which works fine when used through Anthropic's SDK but I'm having issue with vercel's sdk. Here's how to reproduce the issue:

import { createAnthropic } from "@ai-sdk/anthropic";
import { generateText } from "ai";
import dotenv from "dotenv";

dotenv.config();

const anthropic = createAnthropic({
  headers: {
    Authorization: `Bearer ${process.env.AIML_API_KEY}`,
  },
  apiKey: process.env.AIML_API_KEY,
  baseURL: "https://api.aimlapi.com",
});

async function main() {
  while (true) {
    const result = await generateText({
      model: anthropic("claude-3-5-sonnet-20241022"),
      // system: "You reply with <It is what it is> everytime.",
      messages: [
        {
          role: "system",
          content: `You reply with "It is what it is" everytime.`,
        },
        {
          role: "user",
          content: "Tell me about the weather.",
        },
      ],
    });
    
    console.log(result);

    if (result.text) {
      console.log("Reply: ", result.text);
    }
  }
}

main().catch(console.error);

As you can see, I have tried system for the system prompt and in messages as well but I get the following error:

{
  "requestId": "0dcb3d43-3b56-4058-9fca-9320c0546b93",
  "statusCode": 400,
  "timestamp": "2025-01-20T09:25:28.902Z",
  "path": "/messages",
  "meta": [
    {
      "code": "invalid_type",
      "expected": "string",
      "received": "array",
      "path": [
        "system"
      ],
      "message": "Expected string, received array"
    }
  ],
  "message": "Body validation error!"
}

[nabeelraza-7]

The issue was with the provider