The way prediction markets handle this is that there is a limited liquidity at each price. So you offer $100 at 80%, $1000$ at 70%, $10k at 65%, etc. If you said "I'm willing to bet at 90% and someone said, okay I'll bet you $1M you could say no without being a fraud.

I wonder how that works in regard to credal resistance somehow where you could put depth of money you will either bet on or retract the statement 

Biden will win the presidency $50 [45%] $1000 [20%] $10,000 [10%]

Yeah this feels good. 

I think the notation here feels unintuitive. I don't think I'd guess what it means from reading it. 

perhaps: 1 day 80% [5,20], lifetime 80% [2.5, 40] though as I say in the other comment that just feels like a different confidence interval.

I like the idea of your proposal -- communicating how solidified one's credences are should be helpful for quickly communicating on new topics (although I could imagine that one has to be quite good at dealing with probabilities for this to actually provide extra information).

Regarding your particular proposal "CR [ <probability of change>, <min size of change>, <time spent on question> }" is unintuitive to me:

• In "80% CI [5,20]" the probability is denoted with %, while its "unit"-less in your notation
• In "80% CI [5,20]", the braces [] indicate an interval, while it is more of a tuple in your notation

A reformulation might be

80% CI [5,20] CR [0.1, 0.5, 1 day] --> 80% CI [5,20] $\times$10 % CR${}_{1\text{d}}$ [0.5}

Things I dislike about this proposal:

• The "CR${}_{1\text{d}}$" complicates notation. Possibly one could agree on a default time interval such as 1 day and only write the time range explicitly if it differs? Alternatively, "1 day CR" or "CR_1d" might be usable
• the "[0.5]" still feels unintuitive as notation and is still not an interval. Maybe there is a related theoretically-motivated quantity which could be used? Possibly something like the 'expected information gain' can be translated into its influence on the [5,20] intervals (with some reasonable assumptions on the distribution)? 
  • 80% CI [5,20] $\divideontimes$0.5 @ 10 % CR${}_{1\text{d}}$ might be an alternative, with the "\divideontimes" symbol being the $\pm$ of multiplication and hinting at the possible modification of the interval [5, 20]. For latex-free notation, "[5, 20] x0.5" might be a suitable simplified version.

Overall, I don't yet have a good intuition for how to think about expected information gain (especially if it is the expectation of someone else). 
Also, it would be nice if there was a theoretical argument that one of the given numbers is redundant -- getting an impression of what all the 6 numbers mean exactly would take me sufficiently long that it is probably better to just have the whole sentence

My 80% confidence interval is 5-20. I think there's 10% chance I'd change my upper or lower bound by more than 50% of the current value if I spent another ~day investigating this.

But this would of course be less of a problem with experience :)

This % chance of change should fold back into your original forecast, but I like that there is something signalling the depth of your confidence. 

Though it's unclear to me if confidence intervals suggest this notation already. If you had less chance of moving your interval, then it would already be a smaller interval, right?

I'm interested. 

In some way it's a lot like liquidity in a market. You are saying you'll buy $100 at 90% then $200 at 80% etc. Someone can't just come in and force you to bet $1m at 90%. You'd think they had more information than you.