diff --git a/db/migrations/20260720015443_uniform_canonical_ids.go b/db/migrations/20260720015443_uniform_canonical_ids.go
index 69d0907c1..346f22050 100644
--- a/db/migrations/20260720015443_uniform_canonical_ids.go
+++ b/db/migrations/20260720015443_uniform_canonical_ids.go
@@ -79,6 +79,18 @@ var idColumns = []struct{ table, col string }{
 	{"library_tag", "tag_id"},
 }
 
+// embeddedIDColumns holds ids nested inside a larger value; the id-columns guard checks this
+// list against the schema, so every JSON column must appear here or be exempted there.
+var embeddedIDColumns = []struct {
+	table, col string
+	transform  func(string) (string, bool)
+}{
+	{"playqueue", "items", canonicalizeIDList},
+	{"share", "resource_ids", canonicalizeIDList},
+	{"plugin", "users", canonicalizePluginUsers},
+	{"playlist", "rules", canonicalizePlaylistRules},
+}
+
 func upUniformCanonicalIds(ctx context.Context, tx *sql.Tx) error {
 	if err := buildIDMap(ctx, tx); err != nil {
 		return err
@@ -88,17 +100,10 @@ func upUniformCanonicalIds(ctx context.Context, tx *sql.Tx) error {
 			return fmt.Errorf("canonicalizing %s.%s: %w", tc.table, tc.col, err)
 		}
 	}
-	if err := rewriteColumn(ctx, tx, "playqueue", "items", canonicalizeIDList); err != nil {
-		return err
-	}
-	if err := rewriteColumn(ctx, tx, "share", "resource_ids", canonicalizeIDList); err != nil {
-		return err
-	}
-	if err := rewriteColumn(ctx, tx, "plugin", "users", canonicalizePluginUsers); err != nil {
-		return err
-	}
-	if err := rewriteColumn(ctx, tx, "playlist", "rules", canonicalizePlaylistRules); err != nil {
-		return err
+	for _, tc := range embeddedIDColumns {
+		if err := rewriteColumn(ctx, tx, tc.table, tc.col, tc.transform); err != nil {
+			return fmt.Errorf("canonicalizing %s.%s: %w", tc.table, tc.col, err)
+		}
 	}
 	// Legacy PID specs embed old-shaped album/track ids into composite pids; a full rescan
 	// rewrites every pid with the new encoding so path-based move matching stays consistent.
diff --git a/db/migrations/id_canonical_test.go b/db/migrations/id_canonical_test.go
index 55cf8160a..0befbe469 100644
--- a/db/migrations/id_canonical_test.go
+++ b/db/migrations/id_canonical_test.go
@@ -1,6 +1,9 @@
 package migrations
 
 import (
+	"strings"
+
+	"github.com/navidrome/navidrome/model/id"
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
 )
@@ -22,6 +25,18 @@ var _ = Describe("canonicalID", func() {
 		Entry("36 chars without uuid dashes passes through", "000000000000000000000000000000000000", "000000000000000000000000000000000000"),
 	)
 
+	// The exemptions for participants/tags/folder_ids/similar_artists rest on this invariant.
+	It("is the identity on every NewHash id", func() {
+		for _, parts := range [][]string{
+			{""}, {"a"}, {"The Beatles"}, {"genre", "electronic"},
+			{"/music/Artist/Album", "1"}, {strings.Repeat("x", 500)},
+		} {
+			h := id.NewHash(parts...)
+			Expect(h).To(HaveLen(22))
+			Expect(canonicalID(h)).To(Equal(h), "NewHash(%v) = %q was rewritten", parts, h)
+		}
+	})
+
 	It("is idempotent for every shape", func() {
 		for _, s := range []string{"5cLJPkLA5DK2BADhoeotPk", "zzzzzzzzzzzzzzzzzzzzzz",
 			"e3b7fc2ae9447bbec37a13bf916e3cf6", "f47ac10b-58cc-4372-a567-0e02b2c3d479"} {
diff --git a/db/migrations/id_columns_guard_test.go b/db/migrations/id_columns_guard_test.go
index 98c44184f..c4cb3b241 100644
--- a/db/migrations/id_columns_guard_test.go
+++ b/db/migrations/id_columns_guard_test.go
@@ -35,11 +35,28 @@ var _ = Describe("idColumns inventory", func() {
 		for _, tc := range idColumns {
 			covered[tc.table+"."+tc.col] = true
 		}
-		// Columns that are id-named but intentionally not Navidrome canonical ids.
+		for _, tc := range embeddedIDColumns {
+			covered[tc.table+"."+tc.col] = true
+		}
+		// Columns that are id-named or JSON but need no rewrite.
 		exempt := map[string]string{
-			"share.id":    "public share URLs, generated separately",
-			"property.id": "property key, not an entity id",
-			"plugin.id":   "plugin name, not an entity id",
+			"share.id":                       "public share URLs, generated separately",
+			"property.id":                    "property key, not an entity id",
+			"plugin.id":                      "plugin name, not an entity id",
+			"media_file.participants":        "hash-family artist ids, unchanged",
+			"album.participants":             "hash-family artist ids, unchanged",
+			"media_file.tags":                "hash-family tag ids, unchanged",
+			"album.tags":                     "hash-family tag ids, unchanged",
+			"album.folder_ids":               "hash-family folder ids, unchanged",
+			"artist.similar_artists":         "hash-family artist ids, unchanged",
+			"media_file.search_participants": "participant names for FTS, not ids",
+			"album.search_participants":      "participant names for FTS, not ids",
+			"album.discs":                    "disc number -> title map",
+			"media_file.lyrics":              "synced lyrics, no ids",
+			"folder.image_files":             "image file names, no ids",
+			"plugin.manifest":                "plugin-authored manifest, no Navidrome ids",
+			"plugin.config":                  "free-form plugin config, must not be rewritten",
+			"plugin.libraries":               "integer library ids",
 		}
 
 		tables, err := queryColumn(ctx, db, "SELECT name FROM sqlite_master WHERE type='table'")
@@ -56,11 +73,15 @@ var _ = Describe("idColumns inventory", func() {
 				var name, typ string
 				Expect(rows.Scan(&name, &typ)).To(Succeed())
 				lname := strings.ToLower(name)
-				if lname != "id" && lname != "pid" && !strings.HasSuffix(lname, "_id") {
+				utyp := strings.ToUpper(typ)
+				// JSON can hide an id under any key, so every JSON column needs a verdict.
+				isJSON := strings.Contains(utyp, "JSON")
+				isIDName := lname == "id" || lname == "pid" ||
+					strings.HasSuffix(lname, "_id") || strings.HasSuffix(lname, "_ids")
+				if !isJSON && !isIDName {
 					continue
 				}
-				utyp := strings.ToUpper(typ)
-				if !strings.Contains(utyp, "TEXT") && !strings.Contains(utyp, "CHAR") {
+				if !isJSON && !strings.Contains(utyp, "TEXT") && !strings.Contains(utyp, "CHAR") {
 					continue // INTEGER ids (rowid PKs, library.id) are not canonical ids
 				}
 				if strings.HasPrefix(lname, "mbz_") {