diff --git a/e2e/server_test.go b/e2e/server_test.go
index 0b014fc8..bccd6592 100644
--- a/e2e/server_test.go
+++ b/e2e/server_test.go
@@ -1,8 +1,6 @@
 package e2e_test
 
 import (
-	"fmt"
-	"net/http"
 	"strings"
 	"testing"
 	"time"
@@ -187,7 +185,7 @@ func TestProxyServerWithOversizedBlob(t *testing.T) {
 	}
 
 	require.True(t, oversizedError)
-	require.Contains(t, err.Error(), fmt.Sprint(http.StatusBadRequest))
+	require.ErrorIs(t, err, store.ErrProxyOversizedBlob, store.ErrEigenDAOversizedBlob)
 
 }
 
diff --git a/server/server.go b/server/server.go
index 99193ba5..b374db7f 100644
--- a/server/server.go
+++ b/server/server.go
@@ -15,7 +15,6 @@ import (
 	"github.com/Layr-Labs/eigenda-proxy/commitments"
 	"github.com/Layr-Labs/eigenda-proxy/metrics"
 	"github.com/Layr-Labs/eigenda-proxy/store"
-	"github.com/Layr-Labs/eigenda-proxy/utils"
 	"github.com/ethereum-optimism/optimism/op-service/rpc"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/log"
@@ -220,7 +219,9 @@ func (svr *Server) HandlePut(w http.ResponseWriter, r *http.Request) (commitment
 	if err != nil {
 		err = fmt.Errorf("put request failed with commitment %v (commitment mode %v): %w", comm, meta.Mode, err)
 
-		if utils.ErrorMessageContainsAny(err, store.OversizedEigenDAError, store.OversizedProxyError) {
+		if errors.Is(err, store.ErrEigenDAOversizedBlob) || errors.Is(err, store.ErrProxyOversizedBlob) {
+			// we add here any error that should be returned as a 400 instead of a 500.
+			// currently only includes oversized blob requests
 			svr.WriteBadRequest(w, err)
 			return meta, err
 		}
diff --git a/store/eigenda.go b/store/eigenda.go
index 428f25d9..624b8ce5 100644
--- a/store/eigenda.go
+++ b/store/eigenda.go
@@ -66,7 +66,7 @@ func (e EigenDAStore) Put(ctx context.Context, value []byte) ([]byte, error) {
 		return nil, fmt.Errorf("EigenDA client failed to re-encode blob: %w", err)
 	}
 	if uint64(len(encodedBlob)) > e.cfg.MaxBlobSizeBytes {
-		return nil, fmt.Errorf("%s: blob length %d, max blob size %d", OversizedProxyError, len(value), e.cfg.MaxBlobSizeBytes)
+		return nil, fmt.Errorf("%w: blob length %d, max blob size %d", ErrProxyOversizedBlob, len(value), e.cfg.MaxBlobSizeBytes)
 	}
 
 	dispersalStart := time.Now()
diff --git a/store/memory.go b/store/memory.go
index a5ee8457..03b80f70 100644
--- a/store/memory.go
+++ b/store/memory.go
@@ -134,7 +134,7 @@ func (e *MemStore) Get(_ context.Context, commit []byte) ([]byte, error) {
 func (e *MemStore) Put(_ context.Context, value []byte) ([]byte, error) {
 	time.Sleep(e.config.PutLatency)
 	if uint64(len(value)) > e.config.MaxBlobSizeBytes {
-		return nil, fmt.Errorf("%s: blob length %d, max blob size %d", OversizedProxyError, len(value), e.config.MaxBlobSizeBytes)
+		return nil, fmt.Errorf("%w: blob length %d, max blob size %d", ErrProxyOversizedBlob, len(value), e.config.MaxBlobSizeBytes)
 	}
 
 	e.Lock()
diff --git a/store/store.go b/store/store.go
index 98d7a3f8..c48c89d7 100644
--- a/store/store.go
+++ b/store/store.go
@@ -2,6 +2,7 @@ package store
 
 import (
 	"context"
+	"fmt"
 	"strings"
 )
 
@@ -16,9 +17,9 @@ const (
 	Unknown
 )
 
-const (
-	OversizedProxyError   = "encoded blob is larger than max blob size"
-	OversizedEigenDAError = "blob size cannot exceed"
+var (
+	ErrProxyOversizedBlob   = fmt.Errorf("encoded blob is larger than max blob size")
+	ErrEigenDAOversizedBlob = fmt.Errorf("blob size cannot exceed")
 )
 
 func (b BackendType) String() string {
diff --git a/utils/utils.go b/utils/utils.go
index ab9b4cfe..aa83aa95 100644
--- a/utils/utils.go
+++ b/utils/utils.go
@@ -8,21 +8,6 @@ import (
 
 // Helper utility functions //
 
-func ErrorMessageContainsAny(err error, msgs ...string) bool {
-	if err == nil {
-		return false
-	}
-
-	errMsg := err.Error()
-	for _, str := range msgs {
-		if strings.Contains(errMsg, str) {
-			return true
-		}
-	}
-
-	return false
-}
-
 func ContainsDuplicates[P comparable](s []P) bool {
 	seen := make(map[P]struct{})
 	for _, v := range s {