diff --git a/pkg/appview/handlers/api.go b/pkg/appview/handlers/api.go
index ff17a2d..fe40f20 100644
--- a/pkg/appview/handlers/api.go
+++ b/pkg/appview/handlers/api.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"database/sql"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"log"
 	"net/http"
@@ -123,7 +124,7 @@ func (h *UnstarRepositoryHandler) ServeHTTP(w http.ResponseWriter, r *http.Reque
 	err = pdsClient.DeleteRecord(r.Context(), atproto.StarCollection, rkey)
 	if err != nil {
 		// If record doesn't exist, still return success (idempotent)
-		if err.Error() != "record not found" {
+		if !errors.Is(err, atproto.ErrRecordNotFound) {
 			log.Printf("UnstarRepository: Failed to delete star record: %v", err)
 			http.Error(w, fmt.Sprintf("Failed to delete star: %v", err), http.StatusInternalServerError)
 			return
diff --git a/pkg/atproto/client.go b/pkg/atproto/client.go
index dec939c..d99e752 100644
--- a/pkg/atproto/client.go
+++ b/pkg/atproto/client.go
@@ -5,6 +5,7 @@ import (
 	"context"
 	"encoding/base64"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -13,6 +14,11 @@ import (
 	"github.com/bluesky-social/indigo/atproto/client"
 )
 
+// Sentinel errors
+var (
+	ErrRecordNotFound = errors.New("record not found")
+)
+
 // Client wraps ATProto operations for the registry
 type Client struct {
 	pdsEndpoint     string
@@ -118,8 +124,12 @@ func (c *Client) GetRecord(ctx context.Context, collection, rkey string) (*Recor
 		var result Record
 		err := c.indigoClient.Get(ctx, "com.atproto.repo.getRecord", params, &result)
 		if err != nil {
-			if strings.Contains(err.Error(), "404") || strings.Contains(err.Error(), "not found") {
-				return nil, fmt.Errorf("record not found")
+			// Check for RecordNotFound error from indigo's APIError type
+			var apiErr *client.APIError
+			if errors.As(err, &apiErr) {
+				if apiErr.StatusCode == 404 || apiErr.Name == "RecordNotFound" {
+					return nil, ErrRecordNotFound
+				}
 			}
 			return nil, fmt.Errorf("getRecord failed: %w", err)
 		}
@@ -148,12 +158,17 @@ func (c *Client) GetRecord(ctx context.Context, collection, rkey string) (*Recor
 	defer resp.Body.Close()
 
 	if resp.StatusCode == http.StatusNotFound {
-		return nil, fmt.Errorf("record not found")
+		return nil, ErrRecordNotFound
 	}
 
 	if resp.StatusCode != http.StatusOK {
 		bodyBytes, _ := io.ReadAll(resp.Body)
-		return nil, fmt.Errorf("get record failed with status %d: %s", resp.StatusCode, string(bodyBytes))
+		bodyStr := string(bodyBytes)
+		// Check for RecordNotFound error (PDS returns 400 with this error)
+		if strings.Contains(bodyStr, "RecordNotFound") {
+			return nil, ErrRecordNotFound
+		}
+		return nil, fmt.Errorf("get record failed with status %d: %s", resp.StatusCode, bodyStr)
 	}
 
 	var result Record
diff --git a/pkg/atproto/manifest_store.go b/pkg/atproto/manifest_store.go
index 895cb32..00e9db3 100644
--- a/pkg/atproto/manifest_store.go
+++ b/pkg/atproto/manifest_store.go
@@ -3,6 +3,7 @@ package atproto
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"maps"
 	"strings"
@@ -47,7 +48,7 @@ func (s *ManifestStore) Exists(ctx context.Context, dgst digest.Digest) (bool, e
 	_, err := s.client.GetRecord(ctx, ManifestCollection, rkey)
 	if err != nil {
 		// If not found, return false without error
-		if err.Error() == "record not found" {
+		if errors.Is(err, ErrRecordNotFound) {
 			return false, nil
 		}
 		return false, err
diff --git a/pkg/atproto/profile.go b/pkg/atproto/profile.go
index 2b9e3f0..f3b4652 100644
--- a/pkg/atproto/profile.go
+++ b/pkg/atproto/profile.go
@@ -3,6 +3,7 @@ package atproto
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 )
 
@@ -63,28 +64,7 @@ func UpdateProfile(ctx context.Context, client *Client, profile *SailorProfileRe
 	return nil
 }
 
-// isNotFoundError checks if an error is a 404 not found error
+// isNotFoundError checks if an error is a record not found error
 func isNotFoundError(err error) bool {
-	// This is a simple check - in practice, you might need to parse the error more carefully
-	if err == nil {
-		return false
-	}
-	errStr := err.Error()
-	return contains(errStr, "404") || contains(errStr, "not found") || contains(errStr, "RecordNotFound")
-}
-
-// contains checks if a string contains a substring (case-insensitive helper)
-func contains(s, substr string) bool {
-	return len(s) >= len(substr) && (s == substr || len(s) > len(substr) &&
-		(s[:len(substr)] == substr || s[len(s)-len(substr):] == substr ||
-			findSubstring(s, substr)))
-}
-
-func findSubstring(s, substr string) bool {
-	for i := 0; i <= len(s)-len(substr); i++ {
-		if s[i:i+len(substr)] == substr {
-			return true
-		}
-	}
-	return false
+	return errors.Is(err, ErrRecordNotFound)
 }
diff --git a/pkg/hold/registration.go b/pkg/hold/registration.go
index 8d742c3..5206ba3 100644
--- a/pkg/hold/registration.go
+++ b/pkg/hold/registration.go
@@ -3,6 +3,7 @@ package hold
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"log"
 	"net/http"
@@ -288,7 +289,7 @@ func (s *HoldService) hasAllowAllCrewRecord() (bool, error) {
 	record, err := client.GetRecord(ctx, atproto.HoldCrewCollection, "allow-all")
 	if err != nil {
 		// Record doesn't exist
-		if strings.Contains(err.Error(), "not found") {
+		if errors.Is(err, atproto.ErrRecordNotFound) {
 			return false, nil
 		}
 		return false, fmt.Errorf("failed to get crew record: %w", err)