diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index ae87a79cca91af0dea7ba508489f572c81a0d9d5..46ccaf6ab259d4d14da8d4349bb4f50ac20162cf 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -51,7 +51,7 @@ upload:latest:
   before_script:
     - *pre-deploy-uber-space-setup
   script:
-    - sed -i "s,API_VERSION,latest,g" dist/set-payload.schema.json
+    - sed -i "s,SCHEMA_VERSION,latest,g" dist/set-payload.schema.json
     - rsync -Lvz -e "ssh -o CheckHostIP=no" ./dist/set-payload.schema.json fitko@dorado.uberspace.de:schema.fitko.de/fit-connect/set-payload/latest/
 
 upload:release:
@@ -62,5 +62,5 @@ upload:release:
   before_script:
     - *pre-deploy-uber-space-setup
   script:
-    - sed -i "s,API_VERSION,$CI_COMMIT_TAG,g" dist/set-payload.schema.json
+    - sed -i "s,SCHEMA_VERSION,$CI_COMMIT_TAG,g" dist/set-payload.schema.json
     - rsync -Lvz -e "ssh -o CheckHostIP=no" ./dist/set-payload.schema.json fitko@dorado.uberspace.de:schema.fitko.de/fit-connect/set-payload/$CI_COMMIT_TAG/
diff --git a/examples/accept-submission_1.json b/examples/accept-submission_1.json
index d02d8f72c5bdc6cda806f8281648d42776c58f82..4166ba6024d6014a232a13535184f419fa79f394 100644
--- a/examples/accept-submission_1.json
+++ b/examples/accept-submission_1.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "6872b19f-5ee2-47d7-a0e9-ebfe87ab2563",
   "iss": "40847c29-06aa-40e2-bf28-c29884c694c4",
   "iat": 1622796532,
diff --git a/examples/accept-submission_2.json b/examples/accept-submission_2.json
index a832ef79091aea88e34809db33c8aa1c8ace6d1c..0f27da2bff9240a73dfcc937c2125ebbd97c9b1a 100644
--- a/examples/accept-submission_2.json
+++ b/examples/accept-submission_2.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "8538165b-9ce3-4097-871d-5b9581a3b4d9",
   "iss": "40847c29-06aa-40e2-bf28-c29884c694c4",
   "iat": 1622796532,
diff --git a/examples/create-submission_1.json b/examples/create-submission_1.json
index b3931eb33856a3b60e7a9d65f956c6a8cb6fe90f..78525284aa600e2820ad7b0a809f897cc511bc41 100644
--- a/examples/create-submission_1.json
+++ b/examples/create-submission_1.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "ada1b5b4-1bd2-4fab-b236-c30ef88e8c72",
   "iss": "https://submission-api-dev.fit-connect.fitko.dev",
   "iat": 1622796532,
diff --git a/examples/delete-submission_1.json b/examples/delete-submission_1.json
index d43dbef43e9440e34d41571fdab32d39c2c2e05f..3f4d484d2f9b9a2a38707ed08ff19f5364d3fcb0 100644
--- a/examples/delete-submission_1.json
+++ b/examples/delete-submission_1.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "29d091aa-86ab-4806-beb5-fb462d18e2a1",
   "iss": "https://submission-api-dev.fit-connect.fitko.dev",
   "iat": 1622796532,
diff --git a/examples/forward-submission_1.json b/examples/forward-submission_1.json
index ddc58de4589d8c6538ea0d11dacd3fa8cb7198bb..6e99b0d78fabfa125fff5f7c54dae0a26a9ae1ee 100644
--- a/examples/forward-submission_1.json
+++ b/examples/forward-submission_1.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "c0cda2aa-bf79-4427-86f3-9f973bad2ecd",
   "iss": "40847c29-06aa-40e2-bf28-c29884c694c4",
   "iat": 1622796532,
diff --git a/examples/forward-submission_2.json b/examples/forward-submission_2.json
index fa9887385d6ffa83e9a5f357e6ad311fef1fa59c..10bc1430aab553291ae0475b1279655b3ad61c37 100644
--- a/examples/forward-submission_2.json
+++ b/examples/forward-submission_2.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "dbf891c3-1e98-422a-b55a-d628133e5874",
   "iss": "40847c29-06aa-40e2-bf28-c29884c694c4",
   "iat": 1622796532,
diff --git a/examples/notify-submission_1.json b/examples/notify-submission_1.json
index a820b2acd1e7f754c9307bcb2f27c75c5300dcd2..df4fe0bfa4fec0732bb0b01e5d6a8685259e3e13 100644
--- a/examples/notify-submission_1.json
+++ b/examples/notify-submission_1.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "116c3c03-5f31-4d4c-9e65-d36e1e3895f7",
   "iss": "https://submission-api-dev.fit-connect.fitko.dev",
   "iat": 1622796532,
diff --git a/examples/notify-submission_1a.json b/examples/notify-submission_1a.json
deleted file mode 100644
index 53fc94d5983fdeb61528a0af0079c6e8bdd75e29..0000000000000000000000000000000000000000
--- a/examples/notify-submission_1a.json
+++ /dev/null
@@ -1,17 +0,0 @@
-{
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
-  "jti": "b98af532-1f84-436e-8689-0596e91c7c66",
-  "iss": "https://submission-api-dev.fit-connect.fitko.dev",
-  "iat": 1622796532,
-  "sub": "submission:02bf1d9f-282d-4abf-810a-c4104baf0afe",
-  "txn": "case:452b5ee6-35df-441a-bd39-6141723cf914",
-  "events": {
-    "https://schema.fitko.de/fit-connect/events/notify-submission": {
-      "notifyType": "callback",
-      "callback": {
-        "url": "https://www.example.com/callback",
-        "status": 200
-      }
-    }
-  }
-}
diff --git a/examples/notify-submission_2.json b/examples/notify-submission_2.json
index a0891b46ff09c701a35b90a7af0a28604cb91cf1..cf589281cde483811fc58bb0bc9c020b9cac67b4 100644
--- a/examples/notify-submission_2.json
+++ b/examples/notify-submission_2.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "6127ff87-2786-4d0f-90fe-c531672f5de1",
   "iss": "https://submission-api-dev.fit-connect.fitko.dev",
   "iat": 1622796532,
diff --git a/examples/reject-submission_1.json b/examples/reject-submission_1.json
index e0f943fd6eefbe1c499d5ba7acacbeae4debb94d..4eb0b174e8ed15e50b1a74f43cb35ccbd06bba4f 100644
--- a/examples/reject-submission_1.json
+++ b/examples/reject-submission_1.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "4ac47caa-bce1-435a-b04f-3322b224b32e",
   "iss": "40847c29-06aa-40e2-bf28-c29884c694c4",
   "iat": 1622796532,
diff --git a/examples/reject-submission_2.json b/examples/reject-submission_2.json
index 880c07d7eb6eaaa3ea7612b0de502ed03ef3a105..7cb1f6acc93fa429fb7e10fc6d6f68e34d45353e 100644
--- a/examples/reject-submission_2.json
+++ b/examples/reject-submission_2.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "959a274c-419f-4e87-a784-006dc404c415",
   "iss": "40847c29-06aa-40e2-bf28-c29884c694c4",
   "iat": 1622796532,
diff --git a/examples/submit-submission_1.json b/examples/submit-submission_1.json
index 8e99fba5e9c4d6d461d56578c02fdf09be7dae2c..922d703433ae96194fcf997a332e797b9b7c7c81 100644
--- a/examples/submit-submission_1.json
+++ b/examples/submit-submission_1.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json",
+  "$schema": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "jti": "25d2eb77-458d-4c9d-991c-6428c4651646",
   "iss": "https://submission-api-dev.fit-connect.fitko.dev",
   "iat": 1622796532,
diff --git a/spec/problems.schema.json b/spec/problems.schema.json
index aef0492cb5b27f383014bdb713e0bb5fc37df392..bbf887aee65c2cf9a0943914753a097a76e699c5 100644
--- a/spec/problems.schema.json
+++ b/spec/problems.schema.json
@@ -6,16 +6,20 @@
     "type": "object",
     "properties": {
       "type": {
+        "description": "Fehlercode in Form einer URI.",
         "type": "string",
         "pattern": "^https:\\/\\/schema\\.fitko\\.de\\/fit-connect\\/events\\/problems\\/[-a-z]+$"
       },
       "title": {
+        "description": "Für Menschen verständliche Fehlermeldung",
         "type": "string"
       },
       "detail": {
+        "description": "Details zum Fehler, z.B. eine technische Fehlermeldung (optional)",
         "type": "string"
       },
       "instance": {
+        "description": "Betroffener Teil der Übertragung. Mögliche Werte: `submission`, `metadata`, `data`, `attachment:` + UUID des Attachments oder `other`",
         "type": "string",
         "pattern": "^(submission|metadata|data|attachment:.+|other)$"
       }
diff --git a/spec/set-payload.schema.json b/spec/set-payload.schema.json
index cb7505410be35fe1ce24f55d16458e6ea17ba7ac..e87f23ce6787c9d18aebb80354d6a2f252fef7a4 100644
--- a/spec/set-payload.schema.json
+++ b/spec/set-payload.schema.json
@@ -1,38 +1,49 @@
 {
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json",
   "title": "Security Event Token (SET)",
   "description": "Security Event Token (SET) nach RFC 8417",
   "type": "object",
   "properties": {
     "$schema": {
+      "description": "URI des Schemas, dem dieser Security Event Token entspricht.",
       "type": "string",
-      "enum": [ "https://schema.fitko.de/fit-connect/set-payload/1.0.0/set-payload.schema.json" ]
+      "enum": [ "https://schema.fitko.de/fit-connect/set-payload/SCHEMA_VERSION/set-payload.schema.json" ]
     },
     "jti": {
+      "description": "Die JWT ID (jti) ist eine eindeutige UUID für das SET.",
       "type": "string",
       "format": "uuid"
     },
     "iss": {
+      "description": "Als Issuer ('iss') wird die UUID der Destination eingetragen. Bei vom Zustelldienst ausgestellten SETs steht dort die Basis-URL des Zustelldienstes.",
       "type": "string"
     },
     "iat": {
+      "description": "The 'iat' (issued at) claim identifies the time at which the JWT was issued.",
       "type": "integer",
       "minimum": 1577833200
     },
     "sub": {
+      "description": "Das Subject ('sub') enthält 'submission:' und die UUID der Submission.",
       "type": "string",
       "pattern": "^submission:[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$"
     },
     "txn": {
+      "description": "Der Transaction Identifier ('txn') enthält 'case:' und die UUID des Cases.",
       "type": "string",
       "pattern": "^case:[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$"
     },
     "events": {
+      "description": "Enthält genau eines der spezifizierten Events als Unterobjekt.",
       "type": "object",
       "properties": {
         "https://schema.fitko.de/fit-connect/events/create-submission": {
+          "description": "Mit diesem Event dokumentiert der Zustelldienst, dass eine Einreichung angelegt wurde.",
           "type": "object"
         },
         "https://schema.fitko.de/fit-connect/events/submit-submission": {
+          "description": "Mit diesem Event dokumentiert der Zustelldienst, dass die Einreichung abgesendet wurde.",
           "type": "object",
           "properties": {
             "authenticationTags": {
@@ -44,6 +55,7 @@
           ]
         },
         "https://schema.fitko.de/fit-connect/events/notify-submission": {
+          "description": "Mit diesem Event dokumentiert der Zustelldienst, dass das empfangende System Kenntnis von der Einreichung erlangt hat. Wie dies erfolgt ist, wird mit dem Eintrag `notifyType` dokumentiert.",
           "type": "object",
           "properties": {
             "notifyType": {
@@ -59,9 +71,11 @@
           ]
         },
         "https://schema.fitko.de/fit-connect/events/forward-submission": {
+          "description": "Mit diesem Event dokumentiert ein nachgelagertes System, dass es die Einreichung zur Weiterleitung übernommen hat.",
           "type": "object"
         },
         "https://schema.fitko.de/fit-connect/events/reject-submission": {
+          "description": "Mit diesem Event dokumentiert das empfangende System, dass die Einreichung zurückgewiesen wird.",
           "type": "object",
           "properties": {
             "problems": {
@@ -73,6 +87,7 @@
           ]
         },
         "https://schema.fitko.de/fit-connect/events/accept-submission": {
+          "description": "Mit diesem Event dokumentiert das empfangende System, dass die Einreichung akzeptiert wurde.",
           "type": "object",
           "properties": {
             "problems": {
@@ -87,6 +102,7 @@
           ]
         },
         "https://schema.fitko.de/fit-connect/events/delete-submission": {
+          "description": "Mit diesem Event dokumentiert der Zustelldienst, dass die Einreichung gelöscht wurde.",
           "type": "object"
         }
       },