diff --git a/02.md b/02.md
index b467307..48fc02b 100644
--- a/02.md
+++ b/02.md
@@ -191,6 +191,14 @@ A useful flow is:
 - For all new keyset returned here which we don't have yet, get it using `GET /v1/keys/{keyset_id}` and store it
 - If any of the keysets has changed its `active` flag, update it in the db and use the keyset accordingly
 
+## Errors
+
+| Code   | Description                        |
+|--------|------------------------------------|
+| 11002  | Insufficant fee included           |
+| 11003  | Fee over paid                      |
+| 12001  | Keyset is not known                |
+
 [00]: 00.md
 [01]: 01.md
 [02]: 02.md
diff --git a/03.md b/03.md
index c4b1477..4441a5d 100644
--- a/03.md
+++ b/03.md
@@ -78,6 +78,13 @@ If successful, `Bob` will respond with a `PostSwapResponse`
 }
 ```
 
+## Errors
+
+| Code   | Description                               |
+|--------|-------------------------------------------|
+| 11001  | Token is already spent                    |
+| 10002  | Blinded message of output already signed  |
+
 [00]: 00.md
 [01]: 01.md
 [02]: 02.md
diff --git a/04.md b/04.md
index 130efcd..55e918a 100644
--- a/04.md
+++ b/04.md
@@ -212,6 +212,17 @@ Example `MintMethodSetting`:
 }
 ```
 
+## Errors
+
+| Code   | Description                               |
+|--------|-------------------------------------------|
+| 10002  | Blinded message of output already signed  |
+| 11005  | Unit in request is not supported          |
+| 20001  | Quote request is not paid                 |
+| 20002  | Tokens have already been issued for quote |
+| 20003  | Minting is disabled                       |
+
+
 [00]: 00.md
 [01]: 01.md
 [02]: 02.md
diff --git a/05.md b/05.md
index b131671..b3424c4 100644
--- a/05.md
+++ b/05.md
@@ -191,6 +191,17 @@ Example `MeltMethodSetting`:
 }
 ```
 
+## Errors
+
+| Code   | Description                               |
+|--------|-------------------------------------------|
+| 10002  | Blinded message of output already signed  |
+| 11001  | Token is already spent                    |
+| 11005  | Unit in request is not supported          |
+| 20005  | Quote is pending                          |
+| 20006  | Invoice already paid                      |
+
+
 [00]: 00.md
 [01]: 01.md
 [02]: 02.md