Both forms are correct, but imply slightly different things.
1.Tom wants you to pick him up
This states that you know for a fact that Tom, at this very instant, wants you to pick him up. You are asserting that that information you have is accurate and current. Example: "I left Tom at the store and he has no way to get home, so he wants you to pick him up."
2.Tom wanted you to pick him up
This indicates that, at some point in the past, Tom wanted you to pick him up, but leaves some degree of questionability as to the currency of that information. One would use this form in the event that one is unsure what Tom wants at this moment. Example: "I left Tom at the store and he wanted you to pick him up, but since that was two hours ago he may have found another ride home."
The above example makes a positive assertion about Tom's wants in the past, but doesn't indicate if that want still exists in the present. Using wanted implies that maybe you should check with Tom before driving around the store parking lot looking for him.
You haven't written a single thing (or word) right.
The line above is a hyperbolic statement written in the Present Perfect, it suggests that when the person began writing, e.g. a message, an assignment, an email etc. up to the moment they paused, they have continually made writing mistakes. It may even suggest that the person has just finished, and the speaker is scrutinizing the piece of writing at that precise moment.
Imagine a person who started writing at 09.00 in the morning and ‘now’ it's 10.30, the person may still be writing or have just finished, but every line in the text contains an error of some sort. A friend who checks their writing for spelling, punctuation, and grammar mistakes (proofreading), might say
Your writing is riddled with mistakes (or errors)
Note, the Present Simple tense is used here because we are stating a fact.
riddle
2. adjective [verb-link ADJECTIVE with noun]
If something is riddled with undesirable qualities or features, it is full of them.
The first sentence, which was written in PP, can also be rewritten as
You didn't write a single thing right
This construction is more common in American English, it doesn't matter if the time is mentioned or not, nor when the writing was completed. For many speakers of AmEng, the event is understood to have occurred at a specified point in time.
However, if the errors are related to typography blunders for instance, writing Queen Elizabeth I instead of Queen Elizabeth II, or writing dosen't instead of doesn't, you would call that a typo. Typos include spelling and punctuation inaccuracies that typically occur when someone types fast on a keyboard.
If the information given is incorrect for instance, someone writes that Queen Elizabeth I married Sir Francis Drake, you would say that statement was "completely wrong". In fact, she never married.
Best Answer
In my view, without more context, the following sentence has three possible interpretations
In the past the speaker knew, or they had been led to believe, that the listener wrote poetry. The speaker may be expressing their surprise (I was wrong!) or disbelief (where did I get this idea from?) that the listener is not a poet. The statement is equivalent to: “Someone told me you wrote poetry but I now realise that this is not true.”
The speaker expresses their uncertainty as to whether the listener writes poetry now (this may also include the past but we have no way of knowing). The speaker is using the past simple to suggest uncertainty in the present. It is the hesitant equivalent to the statement
“I think you write poetry” = “I think you are a poet"
The speaker discovers that the listener is indeed someone who writes poetry. By stressing the first verb (thought) the speaker is asserting that they had held this belief in the past but they were not certain, this contrasts with the “now”, their finding out the truth. In other words, their former belief has been confirmed. “I thought you wrote poetry (and I was right)"