A delay notice is worth exactly what you can produce eleven months later. Not the wording, not who was right on the day. Whether, when the claim finally lands, you can put the dated notice on the table with the reply attached and the photos it referenced still hanging off it. Most of the time you cannot, because that notice went out as an email, and an email has no owner.
We already had two ways to talk on the record. Every defect carries its own conversation thread, so the back and forth about one crack in one bathroom stays with that crack. RFIs live in their own threaded, attributable form. Both of those are about a thing: a defect, a question against a drawing. What was missing was the correspondence that is not about any one defect. The delay. The variation. The claim. The letter that opens "further to our conversation on site". That was still happening in Outlook, across three people's inboxes, and none of them were the three people who would be in the room when it was disputed.
So we built project correspondence. It sits at project level, next to the daily log, because that is where this kind of paper trail belongs. Against the job, not against a single defect.
Typed, because a claim is not a chat
A thread has a type. General, RFI, delay, variation, claim. You pick it when you open the thread and it filters from there, so when the contract administrator goes looking for every variation on the project they get a list, not a scroll through a chat history.
I will be honest about the bet we took. Typing threads assumes the categories match how disputes actually run, and "general" is where things go to hide. We let a few projects run before we settled the list. Delay, variation and claim earned their spots because those are the three that turn into money. If we have the taxonomy wrong we will hear about it, and that is the sort of thing we would change.
The other side does not get a login
The person you most need on the record is usually the person least likely to install your software. The superintendent. The client's rep. The consultant who answers one email a week.
Externals reply by email magic-link. They get a normal email, they click, they type, and it lands on the thread timestamped and attributed. No account, no password, no "can you resend the invite". It is the same mechanism the contractors already use to close a defect, pointed at correspondence. On our side, making a link that is single-use, safe, and still works on a phone in a car park is a fair bit of plumbing. From the outside it should feel like replying to an email, because that is all we are asking anyone to do.
Attach from what the project already holds
When you cite a photo in a variation it should be the photo already in the project gallery, not a copy someone dragged out of a group chat and re-uploaded at half resolution. Correspondence attaches straight from the project's own photos, documents and drawings. The file you reference is the file on the record, same revision, not a fork of it.
And every email the system sends is logged. Not "an email was sent" but which message, to whom, and when. When someone swears they never received the delay notice, that is a question with an answer now.
What it is not
This is not contract administration. It does not adjudicate a claim or work out what you are owed. It is the record the claim gets built on, and the record is the boring half that nobody keeps until the week they need it and find they cannot.
If you want to see where it sits, it is the correspondence thread in the run-the-job stretch of the features page, next to the daily log and the RFIs. That is the whole of it. The letter that decides who pays should live somewhere you can still find it in eleven months, not in an inbox that belongs to whoever has left the company by then.