Add changelog for 2025-06-27

[quantstruct-bot]

Description

**Create web-based chat sessions with your assistants** using the new [`Web Chat`](https://api.vapi.ai/api#:~:text=WebChat) integration with [`OpenAI Web Chat Requests`](https://api.vapi.ai/api#:~:text=OpenAIWebChatRequest). Accept user input as strings or message arrays and manage conversations with session and customer information.

2. Inworld TTS Voice Provider Integration: You can now customize which language Inworld Voices use like English, Chinese, and Korean. You can also set the TTS model and toggle voice caching with cachingEnabled.

3. Additional Customer Information Fields: You can now include email and externalId fields when creating customers. You can also disable the E164 number format check with numberE164CheckEnabled – setting it to false lets you use non-E164 numbers like 1234 or abc, useful for dialing non-standard numbers on SIP trunks. This lets you store extra contact information and link customers to external systems.

4. schedulePlan No Longer Required in Campaigns: You can now create campaigns without specifying a schedulePlan.

**Behavior Change**: The `Chat.assistantOverrides` property now only supports variable substitution in chat contexts, limiting its functionality compared to previous versions.

Testing Steps

• Run the app locally using fern docs dev or navigate to preview deployment
• Ensure that the changed pages and code snippets work

[github-actions]

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