BUG: AI_TypeValidationError when tool_calls[].index is not defined. #7238
Description
Description
Using SambaNova's Llama-4-Maverick-17B-128E-Instruct returns a tool call without the index parameter.
I believe that tool_calls[].index should be an optional parameter to handle support for more models.
Example code of error
const sambanova = createOpenAI({
apiKey: env.ASSISTANT_SAMBANOVA_API_KEY,
baseURL: 'https://api.sambanova.ai/v1',
headers: HEADERS
})
const model = sambanova("Llama-4-Maverick-17B-128E-Instruct");
const stream = createDataStream({
execute: (dataStream) => {
const result = streamText({
model,
messages: combinedMessages,
maxSteps: 3,
onChunk: ({ chunk }) => {
},
onFinish: async (result) => {
dataStream.writeData(
JSON.stringify({
type: 'finish',
threadId: currentThreadId,
})
);
},
onError: async (error) => {
getLogger().error(
{
message: error.error,
},
'Error while streaming message'
);
},
tools: {
search: tool({
description: `Use hybrid search`,
parameters: z.object({
query: z.string().describe('A query to search the content with.'),
}),
execute: async ({ query }) => {
return query;
},
}),
},
});
result.mergeIntoDataStream(dataStream);
},
});The models raw output.
{
"choices": [
{
"delta": {
"content": null,
"role": "assistant",
"tool_calls": [
{
"function": {
"arguments": "{\"query\":\"getting started\"}",
"name": "search"
},
"id": "call_64d008280bf8423e9f",
"type": "function"
}
]
},
"finish_reason": "tool_calls",
"index": 0,
"logprobs": null
}
],
"created": 1752261507.3932047,
"id": "ba06feb9-6791-449f-a4fb-d974748590f4",
"model": "Llama-4-Maverick-17B-128E-Instruct",
"object": "chat.completion.chunk",
"system_fingerprint": "fastcoe"
}
This call returns an error in the onError callback.
{
"name": "AI_TypeValidationError",
"cause": {
"issues": [
{
"code": "invalid_union",
"unionErrors": [
{
"issues": [
{
"code": "invalid_type",
"expected": "number",
"received": "undefined",
"path": [
"choices",
0,
"delta",
"tool_calls",
0,
"index"
],
"message": "Required"
},
{
"code": "invalid_type",
"expected": "number",
"received": "undefined",
"path": [
"choices",
0,
"delta",
"tool_calls",
1,
"index"
],
"message": "Required"
},
{
"code": "invalid_type",
"expected": "number",
"received": "undefined",
"path": [
"choices",
0,
"delta",
"tool_calls",
2,
"index"
],
"message": "Required"
}
],
"name": "ZodError"
},
{
"issues": [
{
"code": "invalid_type",
"expected": "object",
"received": "undefined",
"path": [
"error"
],
"message": "Required"
}
],
"name": "ZodError"
}
],
"path": [],
"message": "Invalid input"
}
],
"name": "ZodError"
},
"value": {
"choices": [
{
"delta": {
"content": null,
"role": "assistant",
"tool_calls": [
{
"function": {
"arguments": "{\"query\":\"getting started with docs\"}",
"name": "search"
},
"id": "call_40f7adedb11f4fe9a2",
"type": "function"
},
{
"function": {
"arguments": "{\"query\":\"docs guide\"}",
"name": "search"
},
"id": "call_34619b0385134fe185",
"type": "function"
},
{
"function": {
"arguments": "{\"query\":\"documentation guide\"}",
"name": "search"
},
"id": "call_19f41bcc1eea43aab3",
"type": "function"
}
]
},
"finish_reason": "tool_calls",
"index": 0,
"logprobs": null
}
],
"created": 1752262213.163156,
"id": "0f79c8fb-282e-4069-8c88-00860bc47e06",
"model": "Llama-4-Maverick-17B-128E-Instruct",
"object": "chat.completion.chunk",
"system_fingerprint": "fastcoe"
}
}
AI SDK Version
- ai: "^4.3.4"
- @ai-sdk/openai: ^1.3.22