Message Parts contain only one "tool-invocation" type, the latest instead of all the tool invocations in order.

[ephraimduncan]

Description

The message parts contains just a single tool invocation, mainly the latest one instead of the "tool-invocations" in the order which they were called.

[
    {
        "id": "CDaylcB2G0WIabcA",
        "createdAt": "2025-05-15T16:04:36.122Z",
        "role": "user",
        "content": "can you create two events next week monday? two hours apart\n\n\"A call with Yigit\"\n\nthe first event at 9am.",
        "parts": [
            {
                "type": "text",
                "text": "can you create two events next week monday? two hours apart\n\n\"A call with Yigit\"\n\nthe first event at 9am."
            }
        ]
    },
    {
        "id": "0196d4b0-e100-73af-9a2f-26e4de5fb38a",
        "createdAt": "2025-05-15T16:04:38.934Z",
        "role": "assistant",
        "content": "I'll create this event for you:\n\n• **Event**: A call with Yigit\n• **Date**: Monday, May 19, 2025\n• **Time**: 9:00 AM - 10:00 AM\nOkay, I've scheduled **A call with Yigit** for you on Monday, May 19, 2025 from 9:00 AM to 10:00 AM.\nI'll create this event for you:\n\n• **Event**: A call with Yigit\n• **Date**: Monday, May 19, 2025\n• **Time**: 11:00 AM - 12:00 PM\nOkay, I've scheduled **A call with Yigit** for you on Monday, May 19, 2025 from 11:00 AM to 12:00 PM.",
        "parts": [
            {
                "type": "step-start"
            },
            {
                "type": "text",
                "text": "I'll create this event for you:\n\n• **Event**: A call with Yigit\n• **Date**: Monday, May 19, 2025\n• **Time**: 9:00 AM - 10:00 AM\n"
            },
            {
                "type": "tool-invocation",
                "toolInvocation": {
                    "state": "result",
                    "step": 0,
                    "toolCallId": "tool_0_createEvent",
                    "toolName": "createEvent",
                    "args": {
                        "createMeetLink": false,
                        "endTime": "2025-05-19T10:00:00Z",
                        "startTime": "2025-05-19T09:00:00Z",
                        "summary": "A call with Yigit"
                    },
                    "result": {
                        "event": {
                            "id": "5rfvq2ptgdivd906o3qrlbha80",
                            "allDay": false,
                            "calendarId": "primary",
                            "end": "2025-05-19T12:00:00.000Z",
                            "start": "2025-05-19T11:00:00.000Z",
                            "title": "A call with Yigit"
                        },
                        "message": "Event created successfully."
                    }
                }
            },
            {
                "type": "step-start"
            },
            {
                "type": "text",
                "text": "Okay, I've scheduled **A call with Yigit** for you on Monday, May 19, 2025 from 9:00 AM to 10:00 AM.\nI'll create this event for you:\n\n• **Event**: A call with Yigit\n• **Date**: Monday, May 19, 2025\n• **Time**: 11:00 AM - 12:00 PM\n"
            },
            {
                "type": "step-start"
            },
            {
                "type": "text",
                "text": "Okay, I've scheduled **A call with Yigit** for you on Monday, May 19, 2025 from 11:00 AM to 12:00 PM."
            }
        ],
        "toolInvocations": [
            {
                "state": "result",
                "step": 0,
                "toolCallId": "tool_0_createEvent",
                "toolName": "createEvent",
                "args": {
                    "createMeetLink": false,
                    "endTime": "2025-05-19T10:00:00Z",
                    "startTime": "2025-05-19T09:00:00Z",
                    "summary": "A call with Yigit"
                },
                "result": {
                    "event": {
                        "id": "5rfvq2ptgdivd906o3qrlbha80",
                        "allDay": false,
                        "calendarId": "primary",
                        "end": "2025-05-19T12:00:00.000Z",
                        "start": "2025-05-19T11:00:00.000Z",
                        "title": "A call with Yigit"
                    },
                    "message": "Event created successfully."
                }
            },
            {
                "state": "call",
                "step": 1,
                "toolCallId": "tool_0_createEvent",
                "toolName": "createEvent",
                "args": {
                    "createMeetLink": false,
                    "endTime": "2025-05-19T12:00:00Z",
                    "startTime": "2025-05-19T11:00:00Z",
                    "summary": "A call with Yigit"
                }
            }
        ],
        "revisionId": "4flMetwIaSrEkQQz"
    }
]

AI SDK Version

• ai: 4.3.15
• @ai-sdk/react: 1.2.12

[ephraimduncan]

The issue is that i have a lot of tool calls and at the end of the day, it just shows the latest tool invocation in the parts instead of all of them. I want to have them in the order the message streamed in and the order a tool was called, not the tool at the beginning and it keeps changing depending on the message.

[ashersamuel8]

each tool-invocation has an id. you can use that to store the tools in a separate object in the order they're called. each message also has an id and a createdAt property so as an alternative you can use that to extract out the tools from toolInvocations and sort it to get them all in order.

[mohamede1945]

I'm facing a similar issue with gemini models but not with claude. All tool call invocations get the same ID which is always tool_0_{toolName}

[mohamede1945]

For me, it seems an issue with open router. I just tried gemini from AI studio and it generates a unique tool call id.

[ephraimduncan]

I am also using openrouter. I'm going to try without openrouter and report back

[lgrammel]

the tool call ids need to be unique. ai sdk uses them to associate responses with tool calls, and having similar tool call ids for different tool calls will override them

[peterje]

Indeed, this is a major issue. Thought, it is an issue to be solved by OpenRouter, not the AI SDK.

It would be nice if AI SDK surfaced a warning at least for non-unique tool invocation IDs within a chat store. This bug can manifest as some strange behavior and it is not at all obvious that non-unique IDs are the root cause.