First of all I have to admit that the following is mostly not based on knowledge but more or less on educated guessing, so take it with a grain of salt.
Let's first consider hiring a guide in the Alps (maximum height below 5000m). Here the answer, if you will be asked for a tour book should be in nearly all cases "No".
Here we can just divide the tours into two categories, based on how risky they are for the guide. In the "easy" category we can put all tours where the guide could easily go alone as well and just has to take additional care to guarantee for the safety of their guest. The normal routes onto most four-thousander peaks in the Alps will be in this category for example. Here a guide will quite surely not ask for a tour book as they will able to bring you there as long as you are physically and mentally fit enough, as the guide will be able to handle all the technical stuff.
The "hard" category are routes that put also the guide at significant risk and where the guest is not only a passive factor in the safety consideration but has to actively perform tasks such as belaying. Here the guide might ask for a tour book but will ask at least, what you have done before to get an estimation what you are able to do. In this class you surely also won't do a "let's meet in the morning and rush up that dangerous route" like tour, unless you have been on tour with this guide before. So typically you will be together with that guide over several days and do some easier tours before for acclimatisation and to get to know each other.
For all alpine tours there is also one big advantage: You are not far from civilization and there's not much planning and organization required in advance. Typically you also are on tour in small groups of maybe a maximum of five people or so. Therefore, if your guide sees that you are not well enough prepared for the tour, you can just cancel and return to base without greater financial or organizational costs.
For expeditions, things are bit different as there has to be lot of organization beforehand: flights and transportation have to be booked, a time schedule for the approach to the target mountains is made and there are a lot of people involved. In this case, a single person that is unable to cope with the requirements might make the whole expedition fail. You cannot just turn around and walk back to the airport if you are on tour with a 20 person expedition in a remote area.
In this case, the guides in charge will surely want to know if the people they are taking with them will be most likely be able to meet all the requirements for the tour. I know of at least one case, where the guide in charge of a commercial Mount Everest expedition cancelled the whole expedition as he recognized that none of the participants had ever been above 8000m before.
How and what to write into a tour book?
I surfed the websites and catalogs of some expedition organizers but none of them gave some explicit information on what they expect from a tour book. However, I would not spend too much thoughts on that problem as the organizers cannot expect that someone will write such a book just to comply with the requirements of a expedition organizer. So I would just keep some kind of "log" of my activities. Things I would note are:
- group members
- weather and tour conditions
- starting time, time when crucial points (peaks, passes etc., entries to climbing routes) were reached, tour end time
- special occurrences, especially when they significantly influenced the time needed for the tour
Some hard facts like photos or stamps from the huts where you slept will increase authenticity but are more or less optional.
I also would not care too much that they will stalk your tour partners to get information about you. I guess they will ask for the tour books before or at the first planning meetings to see if someone is totally unprepared for the planned expedition. If in doubt, they will ask you and make their own picture of you. A good guide should be able to tell if you are mostly honest about the tours you did or you are just a dazzler. For the case that they were wrong they normally have a clause in their terms and conditions that allows them to exclude you from the the peak ascent and stay in base camp. I guess that is a shame no serious mountaineer wants to go through.