Duplicate Issue Detector

Overview

On every newly-opened GitHub issue, this flow searches the same repository for other open issues whose title closely matches and posts a clickable shortlist of candidates to a Microsoft Teams triage channel. The flow is intentionally non-destructive — it never closes, comments on, or edits the incoming issue; it only surfaces possible duplicates so the person grooming the backlog can act before engineering picks the work up.

Use Case

Backlogs accumulate duplicate issues fast — different reporters describe the same bug with different words, and triagers waste time spotting overlap by hand. This flow catches the obvious cases automatically by leaning on GitHub's own search ranking, so engineers don't end up with two PRs fixing the same thing.

The flow is ideal for teams that:

• Surface possible duplicates within ~3 minutes of issue open.
• Single ranked shortlist posted to Teams, not a wall of noise.
• Never modifies issues — humans stay in the decision loop.
• Fully env-var-driven, so the same solution works against any repo + Teams channel.

Flow Architecture

Environment Variables

Connectors & Connections

Note — All connections are referenced as solution connection references; the flow is portable between environments as long as a connection is mapped at import time.

Customization Guide

Almost every realistic variant of this flow can be implemented by changing environment variable values. A few cases require small edits inside the flow definition — those are called out explicitly below.

Auto-comment with candidates

Add a GitHub CreateComment action after the Select to also drop the duplicate list onto the issue itself.

Tighten matching

Lower per_page from 10 to 3 and require a minimum match score before posting.

Multi-repo coverage

Replace the two GitHub env vars with a JSON env var of [{owner, repo}] and Foreach over it.

Slack instead of Teams

Swap PostMessageToConversation for the Slack PostMessage action and replace the Teams env vars with a Slack channel ID.

Closed issue dedup too

Drop is:open from the Compose query to also surface previously-closed duplicates.

Trigger frequency

Change the GitHub trigger recurrence from 3 minutes to a tighter or looser cadence.

Key Expressions

The flow is intentionally light on Power Fx / WDL gymnastics — the heaviest expressions are the branch-name concatenation and the approval outcome check. They are listed below in the order they appear in the flow.

concat('"', triggerBody()?['title'], '" is:issue is:open repo:', variables('varGitHubOwner'), '/', variables('varGitHubRepository'))

not(equals(item()?['number'], triggerBody()?['number']))

coalesce(body('Search_For_Potential_Duplicates')?['body'], body('Search_For_Potential_Duplicates'))

greater(length(body('Filter_Out_Current_Issue')), 0)