diff --git a/lang/R/inst/extdata/airr-schema.yaml b/lang/R/inst/extdata/airr-schema.yaml
index 036f6d247..7c2435e8e 100644
--- a/lang/R/inst/extdata/airr-schema.yaml
+++ b/lang/R/inst/extdata/airr-schema.yaml
@@ -4631,6 +4631,13 @@ ReceptorReactivity:
             description: End position of the peptide within the reference protein sequence
             x-airr:
                 nullable: true
+        peptide_sequence:
+            type: string
+            description: >
+                The actual peptide sequence against which the receptor reactivity was measured. This field should be
+                used as a convenience for antigens of antigen_type `protein` or `peptide`.
+            x-airr:
+                nullable: true
         mhc_class:
             type: string
             enum:
diff --git a/lang/python/airr/specs/airr-schema.yaml b/lang/python/airr/specs/airr-schema.yaml
index 036f6d247..7c2435e8e 100644
--- a/lang/python/airr/specs/airr-schema.yaml
+++ b/lang/python/airr/specs/airr-schema.yaml
@@ -4631,6 +4631,13 @@ ReceptorReactivity:
             description: End position of the peptide within the reference protein sequence
             x-airr:
                 nullable: true
+        peptide_sequence:
+            type: string
+            description: >
+                The actual peptide sequence against which the receptor reactivity was measured. This field should be
+                used as a convenience for antigens of antigen_type `protein` or `peptide`.
+            x-airr:
+                nullable: true
         mhc_class:
             type: string
             enum:
diff --git a/specs/airr-schema-openapi3.yaml b/specs/airr-schema-openapi3.yaml
index 336db3b70..efa195763 100644
--- a/specs/airr-schema-openapi3.yaml
+++ b/specs/airr-schema-openapi3.yaml
@@ -4919,6 +4919,12 @@ ReceptorReactivity:
             type: integer
             nullable: true
             description: End position of the peptide within the reference protein sequence
+        peptide_sequence:
+            type: string
+            nullable: true
+            description: >
+              The actual peptide sequence against which the receptor reactivity was measured. This field should be
+              used as a convenience for antigens of antigen_type `protein` or `peptide`.
         mhc_class:
             type: string
             nullable: true
diff --git a/specs/airr-schema.yaml b/specs/airr-schema.yaml
index 036f6d247..7c2435e8e 100644
--- a/specs/airr-schema.yaml
+++ b/specs/airr-schema.yaml
@@ -4631,6 +4631,13 @@ ReceptorReactivity:
             description: End position of the peptide within the reference protein sequence
             x-airr:
                 nullable: true
+        peptide_sequence:
+            type: string
+            description: >
+                The actual peptide sequence against which the receptor reactivity was measured. This field should be
+                used as a convenience for antigens of antigen_type `protein` or `peptide`.
+            x-airr:
+                nullable: true
         mhc_class:
             type: string
             enum: