Why Doesn't Devin's Confidence Estimate Match How Hard the Bug Actually Is?
Devin's confidence estimate is a read on the ticket, not a read on the bug. When you turn on scoping mode for Devin's Jira integration, it "analyzes the ticket and posts a scoping comment with a summary, implementation plan, and confidence estimate" before writing any code. That estimate comes entirely from what's written in the ticket body, things like how concrete the repro steps are, how bounded the described change sounds, and whether the acceptance criteria are legible. It has no independent way to know that the customer-reported bug behind those three sentences is actually a race condition that only shows up under load.
So the mismatch isn't a bug in Devin's estimate. It's a mismatch between how well-specified a ticket reads and how hard the underlying problem is. A vague ticket about a genuinely simple fix can score low confidence. A crisp, well-written ticket sitting on top of a gnarly bug can score high confidence, because nothing in the ticket signaled the gnarliness. Devin is scoring the document in front of it, and a support-authored ticket is rarely a complete document.
What the confidence estimate is actually built from
Devin's own docs don't publish a formula for the score. Without a documented basis, the safest assumption is that it's a language-model read of the ticket's clarity and scope, the same kind of judgment a human would make skimming the same three sentences. That's a real signal. It correlates with how much rework Devin will need mid-session. It does not correlate with the actual complexity of the underlying system, because that complexity usually isn't in the ticket at all.
Independent testing backs up the gap between confidence and outcome directly. Answer.AI ran Devin against 20 real engineering tasks and found 14 failures, 3 successes, and 3 inconclusive runs. The team's finding wasn't that Devin failed loudly when it was in over its head. It was the opposite. Devin pressed forward on tasks that were structurally impossible, in one case spending over a day trying to deploy multiple applications to a single Railway deployment, a configuration Railway doesn't support, "hallucinating features that didn't exist" rather than surfacing the blocker. The team's own conclusion was that the autonomous confidence that looked promising going in became a liability, because Devin pursued impossible solutions instead of recognizing them as impossible. Confident and wrong showed up more often than uncertain and cautious.
That pattern scales down to ticket scoping too. A confidence estimate reflects legibility, and legibility and difficulty are just uncorrelated variables. Three things routinely drive them apart:
- The ticket author wasn't the person who hit the bug. Support or a PM paraphrases a customer's report into a ticket, and the paraphrase reads clean. Cleanness is exactly what nudges the confidence estimate up, regardless of what actually breaks underneath.
- The hard part isn't mentioned because nobody found it yet. A ticket that says "CSV export sometimes returns partial rows" reads as one bounded task. Whether that's a pagination off-by-one or a race between the export job and a background delete is invisible from the ticket text, and the estimate has nothing else to weigh.
- Repeat reports don't accumulate in one ticket. If three customers hit the same bug across three separate tickets, each one looks like an isolated, presumably minor report. Nothing in any single ticket tells Devin, or a human triager, that this is the fourth time this month.
When a clean-looking ticket wasn't clean at all
Calder Freight builds dispatch software for regional trucking fleets. Yusuf Kaminski's platform team runs scoping mode on their Jira integration, so Devin posts a plan and a confidence read before anyone assigns real work to it.
A support ticket came in from the app used by dispatchers to reassign a driver mid-route:
Support (filed the ticket from a customer call): Dispatcher can't reassign a load once the driver has started it. The "Reassign" button is there but nothing happens when you click it. Customer said it happened twice this week.
Devin scoped it and posted back:
Devin (scoping comment): Summary: Reassign action appears to no-op for in-progress loads. Implementation plan: locate the reassign handler, add the missing state transition for in-progress loads, add a test. Confidence: High.
The ticket read clean. One button, one described symptom, a plan that sounded like a one-line fix. What it didn't say, because the customer hadn't described it and support had no way to know, was that "started" loads live in two different places at once, an in-memory dispatch queue and a separate database record written by a nightly reconciliation job. The button worked fine against the database record. It silently failed against loads that were in the queue but hadn't been reconciled yet, which only happens in a roughly twenty-minute window after a driver starts a route. Devin's session ran long, produced a fix that patched the database path and left the queue path broken, and the same customer reported the same bug again a week later.
Nothing about that ticket was badly written. It just didn't, and couldn't, contain the fact that two representations of load state existed. The confidence estimate scored the ticket's clarity correctly. It had no way to score the system.
Better tickets have a ceiling
The obvious response is to write more complete tickets. Attach logs, ask the customer follow-up questions, note if this is a repeat report. That helps on its own, whether or not any of this tooling is involved. It also has a ceiling, because the information a better ticket needs often doesn't exist yet at ticket-writing time. Nobody writing that Calder ticket knew about the reconciliation job; that fact only surfaces once someone reads the actual reassignment code, which is the work Devin was supposed to do, not a precondition for it.
The other limit is repetition. Even a well-run support team files each report as its own ticket, in Jira or in Linear, because that's where the conversation happened. Catching that three tickets over three weeks are the same underlying bug, and that the pattern itself is a difficulty signal Devin never sees, is a job that requires looking across tickets and the conversations that produced them, not just reading one at a time carefully.
That's the point where Modem fits. Modem is our product; judge the fit against your own queue rather than taking our word for it. Modem's Devin integration lets the Modem agent hand off a task with the customer context already attached, the original support thread, prior mentions of the same issue across Slack or other tickets, and the repro details customers actually gave, not just the paraphrase that made it into the ticket. If Calder's second report on the same load-reassignment bug had come through Modem instead of landing as a fresh ticket, it would have carried the first incident along with it, the same "started" language, the same dispatcher, a week apart, which is exactly the repeat-report signal a single ticket can't hold on its own. A brief built that way carries that signal into the confidence estimate, so the estimate is scoring something closer to the real problem. It doesn't make the estimate a difficulty oracle, and no version of this tooling will, because some of what makes a bug hard, like Calder's two representations of load state, is still undiscovered until an engineer or an agent is inside the code. It does close the gap that comes from Devin scoping a thinner version of the problem than what customers actually reported. Below that pattern of repeat, scattered reports, writing one careful ticket per issue is the right amount of process, and there's no need to route it through anything else.
For the wider set of ways teams get bugs in front of Devin at all, our guide to handing customer-reported bugs to Devin compares the integrations, the API, and the manual path. And if the underlying issue is that tickets in general arrive thinner than they should, giving coding agents a backlog they can execute covers the ticket-writing discipline that helps regardless of which agent reads it.
“we need SSO before rollout”
“any update on single sign-on?”
“SSO came up twice on this call”
Linear issue, quotes attached
insight report in Notion
DevinOne question before you trust a high-confidence estimate
Before trusting a high-confidence scoping comment, search your support tool and Slack for the exact symptom, not just this ticket's title, and check the last two or three closed tickets in the same product area. Two hits mean you've found a repeat-report signal Devin's scoping comment has no way to hold, and it belongs in the ticket by hand before Devin starts. If support, Slack, and last quarter's closed tickets all stay siloed from each other, that search takes a few extra minutes every time, and most teams stop doing it after a while. That's the habit worth fixing first, independent of any tooling. The ten minutes it costs is cheaper than a fix that comes back a second time.
