Independent study lab
This is an independent, free, learning-only student project. It respects every company and vendor. Trademarks belong to their owners. It is not affiliated with or endorsed by Amazon Web Services, Cisco, Genesys, Salesforce, Twilio, or any other company. If you have a concern, the page will be removed or corrected promptly through the contact form. Nothing here is sold. There are no ads. The author is happy to volunteer for any organization.
Lex in the flow
Confirm before relying. Quotas, prices, and names change.
Get customer input is the Lex block
You associate a Lex V2 bot alias with the instance, often with aws_connect_bot_association or the console, and then the block chooses that alias. The default quota is 70 bots and 100 V2 aliases.
On Connect Customer the worked pricing example charges 0 USD for the Lex speech requests themselves. You still pay for the voice minutes.
- Branch on the intent name you configured, not on the sentence the caller said.
- Slots are empty when the caller hangs up mid-prompt. Handle that.
- DTMF and speech can both fill a slot. Test both.
- A fallback intent should reach a person or a callback.
Source: Get customer input
Slots become attributes or they vanish
After Lex returns, copy the slot values into contact attributes with names the CRM expects. Confirm the slot was filled. An empty slot with a successful intent is normal when the question was optional.
Session attributes can pass context into the next Lex turn. They are not a database.
- Validate the account id in Lambda. Do not trust a spoken string as authorization.
- Barge-in and touchtone buffering change what the caller can interrupt.
- Log the intent and the confidence behavior you actually configured.
- Keep the bot alias stable. Pointing production at a draft alias is how Friday breaks.
Source: Set contact attributes
Fallback is a route, not a failure
Point the fallback intent at a short prompt and a queue, or at a callback when the queue is long. Looping the same question more than twice trains people to hang up.
Use Check queue status or Get metrics if you want the fallback to behave differently when nobody is staffed.
- Timeout and error are different from fallback. Connect them separately.
- A DTMF escape key should exist even in a speech bot.
- Test with noise, with silence, and with an accent the bot has not heard.
- Do not send fallback into another bot with no exit.
Source: Flow types
Sources and go deeper
- Flow block definitions in the flow designer in Connect Customer - Amazon Connect Customer AWS docs. last checked 2026-10
- Add an Amazon Lex bot to Connect Customer - Amazon Connect Customer AWS docs. last checked 2026-10
- What is Amazon Lex V2? - Amazon Lex AWS docs. last checked 2026-10
- Use the flow designer in Connect Customer to create flows - Amazon Connect Customer AWS docs. last checked 2026-10
- Amazon Lex - Wikipedia Wikipedia. last checked 2026-10
- Interactive voice response - Wikipedia Wikipedia. last checked 2026-10
sources.json (lex-get-input) sources.json (lex-slots) sources.json (lex-fallback)