Tidspunktet for avtalen er klart.

Because -et is the definite ending for many neuter nouns in Norwegian.

• et tidspunkt = a time / a point in time
• tidspunktet = the time / the point in time

So Tidspunktet for avtalen means the time for the appointment/agreement.

Avtalen is the definite form of avtale.

• en avtale = an agreement / an appointment
• avtalen = the agreement / the appointment

Norwegian often uses the definite form when both speaker and listener know which thing is being talked about. So here it is not just any agreement or appointment, but the specific one already known in the situation.

Here for avtalen means something like:

• for the appointment
• for the agreement
• of the appointment/agreement, depending on how natural the English translation is

It tells us what the time belongs to or is connected with. So tidspunktet for avtalen is the scheduled time connected to that agreement/appointment.

Because klart agrees with tidspunktet, and tidspunkt is a neuter noun.

In Norwegian, adjectives often change form depending on the noun:

• en bil er klar
• et tidspunkt er klart

So in this sentence:

• subject = tidspunktet
• gender = neuter
• therefore adjective = klart

It is an adjective here.

It comes after er and describes the subject tidspunktet:

• Tidspunktet ... er klart = The time ... is clear/settled

This is called a predicative adjective. It is not functioning as an adverb here.

Klart can mean several related things in Norwegian, and here it usually means:

• clear
• settled
• decided
• fixed

So the sentence can suggest that the time is now known or agreed on.

The sentence follows normal Norwegian main-clause word order:

• Tidspunktet for avtalen = subject
• er = verb
• klart = subject complement

So the pattern is:

• Subject + verb + complement

This is a very standard structure in Norwegian.

Yes, if the rest is understood from context.

• Tidspunktet for avtalen er klart. = full version
• Tidspunktet er klart. = shorter version, if everyone already knows which event you mean

The longer version is just more specific.

It can be either, depending on context.

Common meanings of avtale include:

• agreement
• appointment
• arrangement

So Tidspunktet for avtalen er klart could mean:

• the time of the appointment is settled
• the timing of the agreement/arrangement is clear

Context tells you which English word fits best.

Yes, it is natural and correct.

It sounds a bit formal or neutral, but completely normal. In everyday conversation, people might also say things like:

• Nå er tidspunktet for avtalen klart.
• Nå er tidspunktet bestemt.
• Vi vet nå når avtalen skal være.

But the original sentence is perfectly good Norwegian.