From 4e2bca886ef8bc9ec1f37274e9e5f39a20b9a7da Mon Sep 17 00:00:00 2001
From: Andrew <andrew@signal.org>
Date: Mon, 20 Jul 2026 03:13:04 -0400
Subject: [PATCH] Specify AccountIdentifiers contract more tightly

---
 service/src/main/proto/org/signal/chat/account.proto | 2 +-
 service/src/main/proto/org/signal/chat/common.proto  | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/service/src/main/proto/org/signal/chat/account.proto b/service/src/main/proto/org/signal/chat/account.proto
index 2aa259378..36114b349 100644
--- a/service/src/main/proto/org/signal/chat/account.proto
+++ b/service/src/main/proto/org/signal/chat/account.proto
@@ -103,7 +103,7 @@ message GetAccountIdentityRequest {
 }
 
 message GetAccountIdentityResponse {
-  // A set of account identifiers for the authenticated account.
+  // The identifiers for the authenticated account.
   common.AccountIdentifiers account_identifiers = 1;
 }
 
diff --git a/service/src/main/proto/org/signal/chat/common.proto b/service/src/main/proto/org/signal/chat/common.proto
index 4e49ae536..40c41a15e 100644
--- a/service/src/main/proto/org/signal/chat/common.proto
+++ b/service/src/main/proto/org/signal/chat/common.proto
@@ -25,8 +25,10 @@ message ServiceIdentifier {
   bytes uuid = 2 [(require.exactlySize) = 16];
 }
 
+// All identifiers associated with an account.
 message AccountIdentifiers {
-  // A list of service identifiers for the identified account.
+  // A list of service identifiers for the identified account. Always includes
+  // exactly one ACI service identifier and one PNI service identifier.
   repeated ServiceIdentifier service_identifiers = 1;
 
   // The phone number associated with the identified account.