The short answer
You only pay for messages that deliver a result. If no answer arrives, for example because of a connection error, the message is not charged.
What your credits cover
With credits, you pay for the computing power and AI processing that Mia puts into every answer. This effort arises with every answer, so credits are charged even when the result isn't quite right yet.
Mia supports you in your work, and the engineering decision stays with you. So check results like any other calculation before you use them.
How to get the right result quickly
A follow-up question in the same chat often takes you straight to your goal, because Mia knows the conversation so far. These help most:
Point out what isn't right, for example a value or an assumption.
Add missing details such as the standard, load assumptions, or cross-section.
Ask Mia to show the calculation step by step. That way, you can follow every step.
For demanding tasks, choose the High reasoning tier.
Your feedback counts
Use the feedback on each message to tell us what Mia can do even better. Every piece of feedback helps us develop CALC in a targeted way.