# Error reading 'caps' when joining meeting

**URL:** <https://devforum.zoom.us/t/error-reading-caps-when-joining-meeting/137733>\
**Category:** Meeting SDK\
**Created:** [September 30, 2025, 1:55am UTC](https://devforum.zoom.us/t/error-reading-caps-when-joining-meeting/137733 "2025-09-30T01:55:51Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![amanda-recallai](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/amanda-recallai/32/44747_2.png) [@amanda-recallai](https://devforum.zoom.us/u/amanda-recallai)\
**Post date:** [October 1, 2025, 3:12pm UTC](https://devforum.zoom.us/t/error-reading-caps-when-joining-meeting/137733/2 "2025-10-01T15:12:58Z")

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Hi @andrew.hsu1, this is similar to a known Web SDK issue where the local-recording permission path throws **“reading ‘caps’”** when the host isn’t present yet or meeting metadata isn’t ready - see **[Error in mediaCapturePermission API: TypeError: reading ‘caps’](https://devforum.zoom.us/t/error-in-mediacapturepermission-api-typeerror-cannot-read-properties-of-undefined-reading-caps/96683)**.

If the error is **consistent** , it’s typically because the meeting allows join-before-host and the bot joined first; the permission request needs the **host in the meeting** to resolve, otherwise this exception is raised (documented in **[that thread’s accepted answer](https://devforum.zoom.us/t/error-in-mediacapturepermission-api-typeerror-cannot-read-properties-of-undefined-reading-caps/96683/7)**).

If you aren’t doing recording, skip the recording-permission helpers because the **[Web Meeting SDK does not support local recording](https://devforum.zoom.us/t/need-assistance-with-zoom-meeting-web-sdk-local-recording-feature/107270)**.

If you do need the compliance prompt, only call **[`mediaCapturePermission`](https://marketplacefront.zoom.us/sdk/meeting/web/functions/ZoomMtg.mediaCapturePermission.html)** after you’re fully in-meeting and the **host is present** , and guard for undefined state before reading capability fields.

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_[View the full topic](https://devforum.zoom.us/t/error-reading-caps-when-joining-meeting/137733)._