How can I professionally address repeated lack of detail in user stories without causing tension in the team?

"Back-and-forth clarification during or after development" is an essential part of Agile software development. Since you label the question "agile", and you have a Scrum Master, I assume that you are at least trying to do Agile.

There is a reason that Scrum doesn't make every User Story into a complete requirements document before scheduling it. Doing so would be up-front work at the time the story is created (which might be a long time before it's implemented, or it might never be implemented because it might never be chosen for a sprint). Agile generally considers speculative up-front work to be wasteful.

To restate this another way: in order to provide all the detail needed to implement a User Story, you're going to have to do the "back-and-forth clarification" at some point. In the absence of specific examples, it looks like maybe you object to doing that at the time when the Story is implemented, and would prefer to do it in advance. On the face of it, your belief that back-and-forth is an unnecessary delay seems at odds with Agile practice. Agile says it's a necessary delay. As part of learning Agile you need to learn to take a simple User Story and, in conversation with the product owner and stakeholders, refine and implement it.

That said, it's still possible for a User Story to be unnecessarily vague. It's also possible that your team's Agile practice is broken/compromised: it's not unusual for senior management to declare that things are Agile when in fact the stakeholders aren't available to the team. If the back-and-forth is causing excessive delays then that is the problem. The Agile response is not to abandon Agile, by turning User Stories into complete requirements documents. The Agile response is to seek ways to remove the friction that's slowing down the back-and-forth.

It's also possible that the team is failing to deliver features that stakeholders want (hence "reworking features"), whether that's because of lack of detail in the User Story or some other failure of process. You should raise this by stating the problem (which hopefully everyone can see and agree with) rather than your specific proposed solution (which they very well might not agree with despite agreeing that there's a problem). But, like with the back-and-forth, Agile expects a certain amount of reworking features. On the face it this means Agile is inefficient: why do something twice when you could do it right the first time? But Agile makes a claim on this subject, that overall it is cheaper and more effective to iterate quickly than it is to wait until you're certain of every detail before implementing. If you broadly disagree with that claim then you shouldn't do Agile: or at least you should accept that your team has committed to working this way, regardless of cost.

Anyway, if you have specific issues with the way User Stories are written, or with the fact that your users don't like what you deliver in response to a story, then the team should be willing to explore that. If you want to change User Stories into something different from what User Stories are in Scrum, then the team should be willing to explain why they're never going to do that, and you should be willing to put up with it.

You haven't given any specific examples (and maybe it wouldn't be appropriate to do so), so it's not possible to give a definite answer how to put across the argument for change. If the User Stories you don't like look like, "Add more tests", which isn't a User Story at all, then the argument for changing that is very different from if you'd just prefer that User Stories contain every detail of font and colour before you ever read them.

To recover the situation professionally you need to (in order):

• Be willing to understand the perspective of the entire rest of the team, which thinks that the User Stories are at a good level of detail. You don't state in this question what they have said to you on the subject. Maybe your team is utterly dysfunctional (and they haven't said anything to you, just refused to discuss it). Maybe they have a point of view that you haven't really taken on board. If you're not willing to understand their perspective, then presumably they feel you are just as hostile as you felt them to be.
• Reflect on their position and understand why they need less detail than you do. The fact they don't agree with you doesn't necessarily mean they don't understand you: it's also possible they understand you and think you're wrong.
• Reduce the heat, perhaps by apologising for specific things you've said that you now feel went too far. This doesn't need to be a big deal, since disagreements do get heated and cool off from time to time.
• Accept that you almost certainly will not get things exactly how you want them, since Agile practices inherently are collaborative, and you are in a minority of one in your team.
• Decide what you actually want to achieve, in terms of process change. What specific delays were most expensive, and how would they be preventable? Be mindful that moving work from A to B (or from you to someone else) doesn't reduce cost, so focus on changes that would reduce the total amount of work done.
• Propose those changes, and listen to the reasons given why people disagree with them.
• Make those proposals in the right forum (which for Scrum is a retrospective, not mid-sprint). But, if you want to have a 1-1 conversation with the Scrum Master (or some separate Scrum Coach), about what User Stories are intended to look like in your process, then that doesn't involve the whole team so could be any time.

Also consider what User Stories are there for in Agile. They are a point partway through a conversation among the stakeholders, product owner, and developers, at which a desirable and plausible outcome can be described, but the details are still waiting to be decided at the point of implementation. They are not a Schedule of Work. But by the time they're in a Sprint they also should not just be a random idea someone needed to write down before they forgot, that nobody else has looked at. Maybe there's something you could do before the next Sprint planning meeting, to demonstrate what you mean by improving the quality of a few of the stories. Or maybe you can demonstrate that the unclear stories you don't like get a very wide variance on the story points different people assign to them, whereas clear ones are estimated more-or-less the same by everyone, because you all agree what's being asked and hence how hard it is. Then that's a good indicator that the unclear ones are too unclear, and the clearer ones have a concrete benefit (more certainty in estimating the sprint).

Finally, an example of a bad User Story: "as a developer, I want more detail in User Stories, so that I don't have to discuss them with stakeholders during implementation". The problem with this User Story is that the stated goal is a non-goal of the "product" (your Scrum process). To improve it maybe, "as a developer, I want User Stories to state specific goals, so that I can action the work I'm assigned". The team can probably agree that unactionable stories are bad, hence the goal is good. They might argue whether your particular examples of bad stories actually are unactionable, in which case they can talk about what actions they'd take to clarify whatever is left unclear in the story.

So, the reason I asked my question in the comments shall now become apparent:

Ambiguities often result in back-and-forth clarification during or after development, which causes delays and additional effort to rework features

THIS - this is how you professionally address it.

Afterall, you are completely impartial, right? You don't care if there are delays or re-works, you get paid the same regardless right?

But Management?

Management care about such arcane concepts as 'Profitability' and 'Productivity'.

The way you raise it, is by appealing to what matters to them. Firstly - I would come up with a few good examples:

• A situation where there was a major amount of rework or a delay because of a simple bit of misunderstanding.

  Let's say that the User story didn't specify that 50% of your user base used Linux and that the Dev Team working on the new feature only tested in Windows.

  This is something where a small bit of additional detail would have had a significant impact on a number of decisions.

• Once you have 2-3 examples like the above, you will want to quantify in terms of manhours or Dollars and Cents how much it cost the company

  Because we didn't know that a significant portion of this product's user base used Linux, we never included it in the scope as our other products only have 1-2% Linux users, who use emulation software. This meant we had to spend 3 sprints on reworks, and a total of 300 manhours, or approximately $100K in reworks because this vital bit of information was missed.

• Next, and this is the tricky part, you need to outline the level of detail that is acceptable, what questions need to be asked etc.

And this is the hardest part - because you don't know what you don't know - and to be quite frank, neither do they. If the info is captured, but not recorded - then you will need to make sure it is recorded. If the info is not captured, you will need to make sure that it is. If the info is captured and recorded but still unclear, you need an agreed upon process to rectify it before work gets started.

• Finally - When doing all of this, you want to imagine yourself as a neutral 3rd party observer.

No emotive language, no opinion, no complaining about missing a vacation because of a deadline being pushed. Nothing. Simply stick to your 2-3 examples, the cost to the business and how it could have been prevented.

If you are having regular Retrospectives then you should bring this up during one.

Which a team following Scrum should, but I'm well aware that "Scrum" is a label often used to describe "Any development process that is not waterfall"

How can I recover from this situation professionally and reframe the conversation in a constructive way? I want to improve communication without damaging relationships or team morale.

If you feel you came out a bit confrontational and want to smooth things out, I suggest you approach your Scrum Master and politely ask them for a moment of their time (maybe a 1 on 1 meeting or a quick, private talk somewhere).

Then, I'd keep the "apology" brief and honest, and focus more on your goal and motivation on providing feedback on the user stories. An example phrasing you can use as a starting point and customize:

Hey ScrumMaster, thank you for this moment of your time. I gave it a thought and I want to apologize if in our last conversation my attitude and phrasing came out as confrontational or too blunt. I am very committed to the team and project, and I want to improve the communication on our stories so everything runs more smoothly. I wanted to talk with you a bit more in depth about the user stories, I have some ideas and suggestions I (and the rest of the team) feel could help us have better input for our sprints. For example, last sprint on Story X...

And then proceed to express your concerns and ideas.

Also, how can I better advocate for clearer stories without escalating tension?

Although I don't know to what degree they are unclear, my first suggestion is that you provide an example of a story that was unclear in the past, and also come up and provide an example of how it could have been rephrased/edited to make it clear.

Also, and as I noted in comments, I suggest you also "check yourself" and see if this is not something only you are finding unclear or something only you struggle with. Perhaps consult with other teammates privately what their thoughts on User Stories are, so you can probe if other coworkers are facing similar issues and if they have any suggestions.

There are measures to specifically address this problem built into Scrum. It's called the Refinement or Grooming Meeting.

A lot of teams unfortunately think the Grooming Meeting is just about allocating story points, but in reality its purpose is to make sure stories are ready for execution.

The purpose of a Scrum grooming meeting is to review and refine the product backlog items, ensuring they are ready for upcoming sprints.

Bring this up to your Scrummaster. And when you are in the Grooming Meeting, look at the stories and see if the spec is complete at the necessary level to finish the story. If not then ask those questions.

Are you sure this is a process problem?

There is a long, long history of people thinking scrum is a bullshit fad-diet of an approach to doing software development.

I am not making the case here in this answer on that one way or the other, but if your team is not convinced there's any value-add to this process small wonder that they're just going through the motions with minimal effort and your SM is trying with frantic, neurotic urgency to avoid anything that would shine a light on the ugly truth.

The others answers give fine advice for dealing with this within the system if it is in fact a problem with execution of the process. But I invite you to consider that you are violating the unspoken agreement in the improv theatre of corporate pageantry and so your fellow actors are looking at you funny.

We can't tell from the far side of the internet which way this goes, but that's a perspective I'm surprised nobody mentioned yet.