Bug: tool_use IDs are not unique in claude-agent-sdk 0.1.22

[viniciussantos45]

Description

When using claude-agent-sdk version 0.1.22, the SDK generates duplicate tool_use.id values during agent execution, causing the Claude API to return the following error:

400 invalid_request_error:
messages.X.content.Y: `tool_use` ids must be unique

This happens even when the user does not manually define any tool_use blocks, indicating that the issue is caused by the SDK’s internal tool invocation logic.

Downgrading to claude-agent-sdk 0.1.20 resolves the issue.

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Environment

• OS: macOS
• Python: 3.13.8
• SDK: claude-agent-sdk 0.1.22 (bug)
• SDK: claude-agent-sdk 0.1.20 (working)

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Steps to Reproduce

Using claude-agent-sdk 0.1.22:

import asyncio

from claude_agent_sdk import (
    AssistantMessage,
    ClaudeAgentOptions,
    TextBlock,
    query,
)

async def main():
    options = ClaudeAgentOptions(
        allowed_tools=["Read"],
        system_prompt="You are a helpful coding assistant.",
        cwd=".",
    )

    async for message in query(
        prompt="What is this repository about?",
        options=options,
    ):
        if isinstance(message, AssistantMessage):
            for block in message.content:
                if isinstance(block, TextBlock):
                    print(block.text)

asyncio.run(main())

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Expected Behavior

The agent should successfully execute tool calls and return a response describing the repository.

---

Actual Behavior

The request fails with:

400 invalid_request_error:
messages.X.content.Y: `tool_use` ids must be unique

This suggests that the SDK is reusing the same tool_use.id across multiple internal tool invocations.

---

Workaround

Downgrading the SDK fixes the issue:

pip install claude-agent-sdk==0.1.20

---

Additional Notes

This issue appears when the agent performs multiple internal tool calls (e.g. repeated Read operations).
The user code does not define or reuse tool_use IDs manually — the duplication is fully internal to the SDK.

[ashwin-ant]

We're investigating this

[ashwin-ant]

This should be mitigated now (no update needed).