diff --git a/src/github.rs b/src/github.rs
index c8f6555ba..c2d9e6843 100644
--- a/src/github.rs
+++ b/src/github.rs
@@ -231,6 +231,16 @@ pub struct Label {
     pub name: String,
 }
 
+/// An indicator used to differentiate between an issue and a pull request.
+///
+/// Some webhook events include a `pull_request` field in the Issue object,
+/// and some don't. GitHub does include a few fields here, but they aren't
+/// needed at this time (merged_at, diff_url, html_url, patch_url, url).
+#[derive(Debug, serde::Deserialize)]
+pub struct PullRequestDetails {
+    // none for now
+}
+
 /// An issue or pull request.
 ///
 /// For convenience, since issues and pull requests share most of their
@@ -259,16 +269,12 @@ pub struct Issue {
     pub user: User,
     pub labels: Vec<Label>,
     pub assignees: Vec<User>,
-    /// This is true if this is a pull request.
-    ///
-    /// Note that this field does not come from GitHub. This is manually added
-    /// when the webhook arrives to help differentiate between an event
-    /// related to an issue versus a pull request.
+    /// Indicator if this is a pull request.
     ///
-    /// GitHub *does* actually populate this field on some events, but triagebot ignores that data
-    /// and just stores a bool here when appropriate.
-    #[serde(skip)]
-    pub pull_request: bool,
+    /// This is `Some` if this is a PR (as opposed to an issue). Note that
+    /// this does not always get filled in by GitHub, and must be manually
+    /// populated (because some webhook events do not set it).
+    pub pull_request: Option<PullRequestDetails>,
     /// Whether or not the pull request was merged.
     #[serde(default)]
     pub merged: bool,
@@ -458,7 +464,7 @@ impl Issue {
     }
 
     pub fn is_pr(&self) -> bool {
-        self.pull_request
+        self.pull_request.is_some()
     }
 
     pub async fn get_comment(&self, client: &GithubClient, id: usize) -> anyhow::Result<Comment> {
diff --git a/src/handlers/review_submitted.rs b/src/handlers/review_submitted.rs
index 7fe12f39a..92716aee3 100644
--- a/src/handlers/review_submitted.rs
+++ b/src/handlers/review_submitted.rs
@@ -10,7 +10,8 @@ pub(crate) async fn handle(
         event @ IssueCommentEvent {
             action: IssueCommentAction::Created,
             issue: Issue {
-                pull_request: true, ..
+                pull_request: Some(_),
+                ..
             },
             ..
         },
diff --git a/src/lib.rs b/src/lib.rs
index 09b07de59..e050aba07 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,6 +3,8 @@
 #[macro_use]
 extern crate lazy_static;
 
+use crate::github::PullRequestDetails;
+
 use anyhow::Context;
 use handlers::HandlerError;
 use interactions::ErrorComment;
@@ -143,7 +145,7 @@ pub async fn webhook(
                 .map_err(anyhow::Error::from)?;
 
             log::info!("handling pull request review comment {:?}", payload);
-            payload.pull_request.pull_request = true;
+            payload.pull_request.pull_request = Some(PullRequestDetails {});
 
             // Treat pull request review comments exactly like pull request
             // review comments.
@@ -168,7 +170,7 @@ pub async fn webhook(
                 .context("PullRequestReview(Comment) failed to deserialize")
                 .map_err(anyhow::Error::from)?;
 
-            payload.issue.pull_request = true;
+            payload.issue.pull_request = Some(PullRequestDetails {});
 
             log::info!("handling pull request review comment {:?}", payload);
 
@@ -197,7 +199,7 @@ pub async fn webhook(
                 .map_err(anyhow::Error::from)?;
 
             if matches!(event, EventName::PullRequest) {
-                payload.issue.pull_request = true;
+                payload.issue.pull_request = Some(PullRequestDetails {});
             }
 
             log::info!("handling issue event {:?}", payload);