Fix reasoning model issue by updating chat API to v2

[bitun123]

🛠 Fix: Update Chat API to v2 for Reasoning Model Support

📌 Problem

The v1/chat endpoint does not support reasoning models, causing issues when trying to use them.

✅ Solution

• Updated endpoint from v1/chat → v2/chat
• Ensures proper compatibility with reasoning models

🔍 Changes Made

• Modified API endpoint in fetch request
• No changes to existing logic or UI

🚀 Impact

• Fixes reasoning model usage
• Improves API compatibility
• No breaking changes

🧪 Testing

• Verified reasoning model works correctly with v2
• No regressions observed

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Note

Medium Risk
Low code complexity but changes the network endpoint used by chatStream, which could alter response shape/behavior or break users if their backend expects v1 semantics.

Overview
Switches the SDK’s streamed chat request (chatStream) from hitting v1/chat to v2/chat to support reasoning models.

Adds a short README note documenting the endpoint version update and the rationale.

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

V1 request/response format sent to V2 endpoint

High Severity

The endpoint URL was changed from v1/chat to v2/chat, but the request type (ChatStreamRequest), request serializer (serializers.ChatStreamRequest), response parser (serializers.StreamedChatResponse), streaming response type ("streaming" vs "sse"), and event shape ("json" with "\n" terminator vs "sse" with "[DONE]" terminator) all remain v1-format. The v1 request uses a message string field, while v2 expects a messages array with role/content objects — these are completely incompatible schemas. This will cause all chatStream calls to fail at the API level.

Additional Locations (2)

• src/Client.ts#L113-L114
• src/Client.ts#L120-L144

 

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