diff --git a/backend/src/s9pk/manifest.rs b/backend/src/s9pk/manifest.rs
index 567ec447d..76a190a91 100644
--- a/backend/src/s9pk/manifest.rs
+++ b/backend/src/s9pk/manifest.rs
@@ -2,6 +2,7 @@ use std::borrow::Borrow;
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
 
+use color_eyre::eyre::eyre;
 use patch_db::HasModel;
 use serde::{Deserialize, Serialize, Serializer};
 use url::Url;
@@ -17,6 +18,7 @@ use crate::status::health_check::HealthChecks;
 use crate::util::Version;
 use crate::version::{Current, VersionT};
 use crate::volume::Volumes;
+use crate::Error;
 
 pub const SYSTEM_PACKAGE_ID: PackageId<&'static str> = PackageId(SYSTEM_ID);
 
@@ -210,6 +212,23 @@ pub struct Description {
     pub short: String,
     pub long: String,
 }
+impl Description {
+    pub fn validate(&self) -> Result<(), Error> {
+        if self.short.chars().skip(160).next().is_some() {
+            return Err(Error::new(
+                eyre!("Short description must be 160 characters or less."),
+                crate::ErrorKind::ValidateS9pk,
+            ));
+        }
+        if self.long.chars().skip(5000).next().is_some() {
+            return Err(Error::new(
+                eyre!("Long description must be 5000 characters or less."),
+                crate::ErrorKind::ValidateS9pk,
+            ));
+        }
+        Ok(())
+    }
+}
 
 #[derive(Clone, Debug, Default, Deserialize, Serialize)]
 #[serde(rename_all = "kebab-case")]
diff --git a/backend/src/s9pk/reader.rs b/backend/src/s9pk/reader.rs
index af81811e8..57a78deee 100644
--- a/backend/src/s9pk/reader.rs
+++ b/backend/src/s9pk/reader.rs
@@ -149,6 +149,7 @@ impl<R: AsyncRead + AsyncSeek + Unpin> S9pkReader<R> {
             .into_iter()
             .map(|i| i.validate(&man.id, &man.version).map(|_| i.image_id))
             .collect::<Result<BTreeSet<ImageId>, _>>()?;
+        man.description.validate()?;
         man.actions
             .0
             .iter()