Sub Issues

# Step 1: Create the issue and capture its numeric ID
ISSUE_ID=$(gh api repos/{owner}/{repo}/issues \
  -X POST \
  -f title="Sub-task title" \
  -f body="Description" \
  --jq '.id')

# Step 2: Link it as a sub-issue of the parent
# IMPORTANT: sub_issue_id must be an integer. Use --input (not -f) to send JSON.
echo "{\"sub_issue_id\": $ISSUE_ID}" | gh api repos/{owner}/{repo}/issues/{parent_number}/sub_issues -X POST --input -

gh api repos/{owner}/{repo}/issues/{issue_number}/sub_issues

gh api repos/{owner}/{repo}/issues/{issue_number}/parent

# sub_issue_id is the numeric issue ID (not the issue number)
# Get it from the .id field when creating or fetching an issue
echo '{"sub_issue_id": 12345}' | gh api repos/{owner}/{repo}/issues/{parent_number}/sub_issues -X POST --input -

echo '{"sub_issue_id": 12345}' | gh api repos/{owner}/{repo}/issues/{parent_number}/sub_issue -X DELETE --input -

echo '{"sub_issue_id": 6, "after_id": 5}' | gh api repos/{owner}/{repo}/issues/{parent_number}/sub_issues/priority -X PATCH --input -

{
  repository(owner: "OWNER", name: "REPO") {
    issue(number: 123) {
      parent { number title }
      subIssues(first: 50) {
        nodes { number title state }
      }
      subIssuesSummary { total completed percentCompleted }
    }
  }
}

mutation {
  addSubIssue(input: {
    issueId: "PARENT_NODE_ID"
    subIssueId: "CHILD_NODE_ID"
  }) {
    issue { id }
    subIssue { id number title }
  }
}

mutation {
  createIssue(input: {
    repositoryId: "REPO_NODE_ID"
    title: "Implement login validation"
    parentIssueId: "PARENT_NODE_ID"
  }) {
    issue { id number }
  }
}

mutation {
  removeSubIssue(input: {
    issueId: "PARENT_NODE_ID"
    subIssueId: "CHILD_NODE_ID"
  }) {
    issue { id }
  }
}

mutation {
  reprioritizeSubIssue(input: {
    issueId: "PARENT_NODE_ID"
    subIssueId: "CHILD_NODE_ID"
    afterId: "OTHER_CHILD_NODE_ID"
  }) {
    issue { id }
  }
}