diff --git a/swarm-review-classifier/src/run.rs b/swarm-review-classifier/src/run.rs
index 1f60e91c1..afe358e9b 100644
--- a/swarm-review-classifier/src/run.rs
+++ b/swarm-review-classifier/src/run.rs
@@ -186,35 +186,6 @@ impl KeySource for Store {
     }
 }
 
-/// `e` and each of its sources, joined by `: `. The store client's errors
-/// carry only a generic message at the top; the URL and the failure kind sit
-/// below it. For login errors only: they hold URLs and error kinds, not values.
-fn chain(e: &dyn std::error::Error) -> String {
-    let mut out = e.to_string();
-    let mut next = e.source();
-    while let Some(cause) = next {
-        out.push_str(": ");
-        out.push_str(&cause.to_string());
-        next = cause.source();
-    }
-    out
-}
-
-/// The run failure for a store login that failed with `e`.
-fn login_failure(what: &str, e: &dyn std::error::Error) -> String {
-    format!(
-        "logging in to the secret store to read the {what}: {}",
-        chain(e)
-    )
-}
-
-/// The run failure for a store read that failed with `e`. Shows `e` alone:
-/// a parse error's sources quote the stored value, and the failure text ends
-/// up in a review comment.
-fn read_failure(path: &str, e: &dyn std::error::Error) -> String {
-    format!("reading secret/{path}: {e}")
-}
-
 /// The key `field` takes from the object at `path`, trimmed; `None` when
 /// nothing or a blank is stored.
 async fn read_key<T: serde::de::DeserializeOwned>(
@@ -224,11 +195,11 @@ async fn read_key<T: serde::de::DeserializeOwned>(
 ) -> Result<Option<String>, String> {
     let store = swarm_secret_client::SecretStore::from_env(crate::CERT_ROLE)
         .await
-        .map_err(|e| login_failure(what, &e))?;
+        .map_err(|e| format!("logging in to the secret store to read the {what}: {e}"))?;
     let stored: Option<T> = store
         .read_optional(path)
         .await
-        .map_err(|e| read_failure(path, &e))?;
+        .map_err(|e| format!("reading secret/{path}: {e}"))?;
     Ok(stored
         .map(field)
         .map(|key| key.trim().to_owned())
@@ -409,69 +380,6 @@ mod tests {
 
     use super::*;
 
-    /// A failure with a cause, as the store client's errors nest them.
-    #[derive(Debug)]
-    struct Level(&'static str, Option<Box<Level>>);
-
-    impl std::fmt::Display for Level {
-        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-            f.write_str(self.0)
-        }
-    }
-
-    impl std::error::Error for Level {
-        fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
-            self.1.as_deref().map(|l| l as _)
-        }
-    }
-
-    /// A parse failure whose source quotes the stored value.
-    #[derive(Debug)]
-    struct Unparsable(serde_json::Error);
-
-    impl std::fmt::Display for Unparsable {
-        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-            f.write_str("error parsing the response")
-        }
-    }
-
-    impl std::error::Error for Unparsable {
-        fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
-            Some(&self.0)
-        }
-    }
-
-    #[test]
-    fn read_failure_leaves_out_the_stored_value() {
-        let cause = serde_json::from_str::<u32>("\"hunter2\"").unwrap_err();
-        assert!(cause.to_string().contains("hunter2"), "control");
-        let text = read_failure("p", &Unparsable(cause));
-        assert_eq!(text, "reading secret/p: error parsing the response");
-    }
-
-    #[test]
-    fn chain_renders_every_level() {
-        let e = Level(
-            "An error occurred with the request",
-            Some(Box::new(Level(
-                "error sending request for url (https://bao/v1/auth/cert/login)",
-                Some(Box::new(Level("tls handshake eof", None))),
-            ))),
-        );
-        assert_eq!(
-            chain(&e),
-            "An error occurred with the request: error sending request for url \
-             (https://bao/v1/auth/cert/login): tls handshake eof"
-        );
-        assert_eq!(
-            login_failure("API key", &e),
-            "logging in to the secret store to read the API key: An error occurred with the \
-             request: error sending request for url (https://bao/v1/auth/cert/login): tls \
-             handshake eof"
-        );
-        assert_eq!(chain(&Level("alone", None)), "alone");
-    }
-
     /// The API key runtime's key is `k` and the ACP runtime's `p`, or both
     /// fail with the same error.
     struct Key(Result<(), &'static str>);