51003: Client Connection: identity too long

The identity value in your Access Token exceeds the maximum length allowed for a Twilio client connection. Twilio rejects the connection request when the token contains an identity that is too long.

• Your application generates an Access Token with an identity string that exceeds the product limit.
• Your application passes unbounded user input, such as an email address, UUID collection, or concatenated account data, into the identity field.
• Your token generation logic appends environment, tenant, or session metadata to identity, causing it to exceed the allowed length.

• Shorten the identity value you include in the Access Token.
• Use a stable, compact identifier for each user instead of a long descriptive string.
• Update your token generation logic to validate the length of identity before creating the Access Token.
• If you need to associate additional user metadata with the client, store that data in your application instead of embedding it in identity.
• Review the Access Token documentation for your Twilio SDK product and confirm that your generated token matches the required client identity format.

• Access Tokens
• Conversations documentation
• Sync documentation