diff --git a/api/swagger.yaml b/api/swagger.yaml
index 286d223e8e..d789374b1a 100644
--- a/api/swagger.yaml
+++ b/api/swagger.yaml
@@ -1154,6 +1154,13 @@ definitions:
   ContainerConfig:
     description: |
       Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/api/types/types.go b/api/types/types.go
index b2c2a78359..4f06c8064f 100644
--- a/api/types/types.go
+++ b/api/types/types.go
@@ -73,8 +73,11 @@ type ImageInspect struct {
 	// Depending on how the image was created, this field may be empty.
 	Container string
 
-	// ContainerConfig is the configuration of the container that was committed
-	// into the image.
+	// ContainerConfig is an optional field containing the configuration of the
+	// container that was last committed when creating the image.
+	//
+	// Previous versions of Docker builder used this field to store build cache,
+	// and it is not in active use anymore.
 	ContainerConfig *container.Config
 
 	// DockerVersion is the version of Docker that was used to build the image.
diff --git a/docs/api/v1.30.yaml b/docs/api/v1.30.yaml
index db609e76ae..42967f4553 100644
--- a/docs/api/v1.30.yaml
+++ b/docs/api/v1.30.yaml
@@ -757,7 +757,15 @@ definitions:
               - "hyperv"
 
   ContainerConfig:
-    description: "Configuration for a container that is portable between hosts"
+    description: |
+      Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.31.yaml b/docs/api/v1.31.yaml
index 0f676395ea..ce2022adb9 100644
--- a/docs/api/v1.31.yaml
+++ b/docs/api/v1.31.yaml
@@ -758,7 +758,15 @@ definitions:
               - "hyperv"
 
   ContainerConfig:
-    description: "Configuration for a container that is portable between hosts"
+    description: |
+      Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.32.yaml b/docs/api/v1.32.yaml
index 154ffd936d..220ccc0041 100644
--- a/docs/api/v1.32.yaml
+++ b/docs/api/v1.32.yaml
@@ -821,7 +821,15 @@ definitions:
               - "hyperv"
 
   ContainerConfig:
-    description: "Configuration for a container that is portable between hosts"
+    description: |
+      Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.33.yaml b/docs/api/v1.33.yaml
index 00293dd092..8372356fb1 100644
--- a/docs/api/v1.33.yaml
+++ b/docs/api/v1.33.yaml
@@ -826,7 +826,15 @@ definitions:
               - "hyperv"
 
   ContainerConfig:
-    description: "Configuration for a container that is portable between hosts"
+    description: |
+      Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.34.yaml b/docs/api/v1.34.yaml
index 7247b03a8e..35ebb43ed1 100644
--- a/docs/api/v1.34.yaml
+++ b/docs/api/v1.34.yaml
@@ -837,7 +837,15 @@ definitions:
               - "hyperv"
 
   ContainerConfig:
-    description: "Configuration for a container that is portable between hosts"
+    description: |
+      Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.35.yaml b/docs/api/v1.35.yaml
index c2ec825afc..353bd7b90a 100644
--- a/docs/api/v1.35.yaml
+++ b/docs/api/v1.35.yaml
@@ -817,7 +817,15 @@ definitions:
               - "hyperv"
 
   ContainerConfig:
-    description: "Configuration for a container that is portable between hosts"
+    description: |
+      Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.36.yaml b/docs/api/v1.36.yaml
index 371eddd030..880ad31e96 100644
--- a/docs/api/v1.36.yaml
+++ b/docs/api/v1.36.yaml
@@ -817,7 +817,15 @@ definitions:
               - "hyperv"
 
   ContainerConfig:
-    description: "Configuration for a container that is portable between hosts"
+    description: |
+      Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.37.yaml b/docs/api/v1.37.yaml
index 4d0d6b2d02..de9183cdef 100644
--- a/docs/api/v1.37.yaml
+++ b/docs/api/v1.37.yaml
@@ -821,7 +821,15 @@ definitions:
               - "hyperv"
 
   ContainerConfig:
-    description: "Configuration for a container that is portable between hosts"
+    description: |
+      Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.38.yaml b/docs/api/v1.38.yaml
index d1c64959f0..b30e410fd0 100644
--- a/docs/api/v1.38.yaml
+++ b/docs/api/v1.38.yaml
@@ -832,7 +832,15 @@ definitions:
               type: "string"
 
   ContainerConfig:
-    description: "Configuration for a container that is portable between hosts"
+    description: |
+      Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.39.yaml b/docs/api/v1.39.yaml
index d04a8571d4..ef1066edb7 100644
--- a/docs/api/v1.39.yaml
+++ b/docs/api/v1.39.yaml
@@ -1067,6 +1067,13 @@ definitions:
   ContainerConfig:
     description: |
       Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.40.yaml b/docs/api/v1.40.yaml
index 9630167b47..e78552d540 100644
--- a/docs/api/v1.40.yaml
+++ b/docs/api/v1.40.yaml
@@ -1128,6 +1128,13 @@ definitions:
   ContainerConfig:
     description: |
       Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname:
diff --git a/docs/api/v1.41.yaml b/docs/api/v1.41.yaml
index b8be833356..c37be855d3 100644
--- a/docs/api/v1.41.yaml
+++ b/docs/api/v1.41.yaml
@@ -1160,6 +1160,13 @@ definitions:
   ContainerConfig:
     description: |
       Configuration for a container that is portable between hosts.
+
+      When used as `ContainerConfig` field in an image, `ContainerConfig` is an
+      optional field containing the configuration of the container that was last
+      committed when creating the image.
+
+      Previous versions of Docker builder used this field to store build cache,
+      and it is not in active use anymore.
     type: "object"
     properties:
       Hostname: