diff --git a/src/modules/repo/services/octo.ts b/src/modules/repo/services/octo.ts
index 659c0ba..d05314b 100644
--- a/src/modules/repo/services/octo.ts
+++ b/src/modules/repo/services/octo.ts
@@ -1,6 +1,6 @@
 import { Octokit } from "@octokit/rest"
 
-import { getAccessToken } from "@/modules/user/service/signIn"
+import { getAccessToken, refreshToken } from "@/modules/user/service/signIn"
 
 export const DEFAULT_OCTOKIT_TIMEOUT_MS = 8_000
 
@@ -20,3 +20,21 @@ export const getOctokit = async (): Promise<Octokit> => {
 
   return octokit
 }
+
+const isUnauthorized = (error: unknown): boolean =>
+  (error as { status?: number })?.status === 401
+
+// Runs an Octokit call; on 401, force-refreshes the token and retries once.
+// Rethrows the original error if the refresh fails or the retry still 401s.
+export const runWithAuthRetry = async <T>(
+  call: (octokit: Octokit) => Promise<T>
+): Promise<T> => {
+  try {
+    return await call(await getOctokit())
+  } catch (error) {
+    if (!isUnauthorized(error)) throw error
+    const refreshed = await refreshToken({ force: true }).catch(() => null)
+    if (!refreshed) throw error
+    return await call(await getOctokit())
+  }
+}
diff --git a/src/modules/user/service/signIn.ts b/src/modules/user/service/signIn.ts
index bf877a1..2a37f89 100644
--- a/src/modules/user/service/signIn.ts
+++ b/src/modules/user/service/signIn.ts
@@ -38,7 +38,13 @@ export const needToRefreshToken = async () => {
   return isBefore(expirationDate, minimumViableDate)
 }
 
-export const refreshToken = async () => {
+let inFlightRefresh: Promise<GithubAccessToken | null> | null = null
+
+const performRefresh = async ({
+  force
+}: {
+  force: boolean
+}): Promise<GithubAccessToken | null> => {
   const accessToken = await data.get<
     DataType.GithubAccessToken,
     GithubAccessToken
@@ -48,7 +54,7 @@ export const refreshToken = async () => {
     return null
   }
 
-  const needRefresh = await needToRefreshToken()
+  const needRefresh = force || (await needToRefreshToken())
 
   if (needRefresh) {
     const authenticationServerURL = new URL(AUTHENTICATION_SERVER)
@@ -70,6 +76,18 @@ export const refreshToken = async () => {
   return accessToken
 }
 
+// GitHub refresh tokens are single-use, so concurrent refreshes race and the
+// loser ends up with a revoked refresh token. Dedupe in-flight calls.
+export const refreshToken = async ({
+  force = false
+}: { force?: boolean } = {}): Promise<GithubAccessToken | null> => {
+  if (inFlightRefresh) return inFlightRefresh
+  inFlightRefresh = performRefresh({ force }).finally(() => {
+    inFlightRefresh = null
+  })
+  return inFlightRefresh
+}
+
 export const getAccessToken = async () => {
   const response = await data.get<
     DataType.GithubAccessToken,