Generally, yes. You have a right to discovery of anything that they plan to introduce at trial against you, or anything that would cast doubt on your guilt (exculpatory evidence).
Most facts, yes. Non-disclosure is the exception, not the rule, thanks to the Sixth Amendment's right to a fair trial. However, when national security is involved, the Classified Information Protection Act (CIPA) may apply, and some evidence may be reserved for in camera hearings.
Also, if the information would not exculpate the defendant, and the prosecution won't introduce it at trial as evidence of guilt, then the information can be withheld.
I'm on the verge of not trusting the US govt when they prosecute things. Epstein details being proclaimed and then hiding them is just the start. If the large and formerly mostly independent and trustworthy federal law enforcement groups can't disclose info there, what should make you feel like they are honest?
Good point, criminal trial process is not obviously corrupted like the pre-trial. Every day recently there's a story about trump trying to get his political enemies prosecuted, and then he fired people who investigated him from his last term.
An indictment is pre-trial. To get a criminal indictment, all you need to show to a grand jury is "probable cause," which is a very low standard--the same standard needed to justify an arrest. That's the reason for the old joke about being able to indict a ham sandwich.
Now that Comey's been indicted, the trial process will begin, assuming he doesn't plea out (and I don't think he will). The uphill battle for the prosecution now begins.