diff --git a/internal/httpapi/server.go b/internal/httpapi/server.go
index 0831b1cdc..f14ef6de5 100644
--- a/internal/httpapi/server.go
+++ b/internal/httpapi/server.go
@@ -7277,7 +7277,7 @@ func (s *Server) handleSetToolEnabled(w http.ResponseWriter, r *http.Request) {
 	}
 
 	serverID := chi.URLParam(r, "id")
-	toolName := chi.URLParam(r, "tool")
+	toolName := decodePathParam(chi.URLParam(r, "tool"))
 	if serverID == "" || toolName == "" {
 		s.writeError(w, r, http.StatusBadRequest, "Server ID and tool name required")
 		return
@@ -7404,7 +7404,7 @@ func (s *Server) handleSetAllToolsEnabled(enabled bool) http.HandlerFunc {
 
 func (s *Server) handleGetToolDiff(w http.ResponseWriter, r *http.Request) {
 	serverID := chi.URLParam(r, "id")
-	toolName := chi.URLParam(r, "tool")
+	toolName := decodePathParam(chi.URLParam(r, "tool"))
 
 	if serverID == "" || toolName == "" {
 		s.writeError(w, r, http.StatusBadRequest, "Server ID and tool name required")
diff --git a/internal/httpapi/tool_path_param_decode_test.go b/internal/httpapi/tool_path_param_decode_test.go
new file mode 100644
index 000000000..e4e8efc02
--- /dev/null
+++ b/internal/httpapi/tool_path_param_decode_test.go
@@ -0,0 +1,67 @@
+package httpapi
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/zap"
+
+	"github.com/smart-mcp-proxy/mcpproxy-go/internal/storage"
+)
+
+// TestToolSubresource_EncodedToolNameUnescaped: chi routes on RawPath, so the
+// {tool} param arrives percent-encoded whenever the encoding differs from Go's
+// default (the Web UI sends encodeURIComponent(toolName), which encodes ':' and
+// '/'). Tool names such as "ns:erase" or "ns/erase" must be decoded before the
+// exact-match approval lookup, the same way {id} is (MCP-1118).
+func TestToolSubresource_EncodedToolNameUnescaped(t *testing.T) {
+	for _, tc := range []struct{ encoded, decoded string }{
+		{"ns%3Aerase", "ns:erase"},
+		{"ns%2Ferase", "ns/erase"},
+	} {
+		newCtrl := func() *mockToolQuarantineController {
+			return &mockToolQuarantineController{
+				apiKey: "test-key",
+				approvals: []*storage.ToolApprovalRecord{{
+					ServerName:          "github",
+					ToolName:            tc.decoded,
+					Status:              storage.ToolApprovalStatusChanged,
+					PreviousDescription: "old",
+					CurrentDescription:  "new",
+				}},
+			}
+		}
+
+		t.Run("GET diff "+tc.decoded, func(t *testing.T) {
+			server := NewServer(newCtrl(), zap.NewNop().Sugar(), nil)
+			req := httptest.NewRequest(http.MethodGet, "/api/v1/servers/github/tools/"+tc.encoded+"/diff", nil)
+			req.Header.Set("X-API-Key", "test-key")
+			w := httptest.NewRecorder()
+			server.ServeHTTP(w, req)
+
+			require.Equal(t, http.StatusOK, w.Code, "body=%s", w.Body.String())
+			var resp map[string]interface{}
+			require.NoError(t, json.Unmarshal(w.Body.Bytes(), &resp))
+			data := resp["data"].(map[string]interface{})
+			assert.Equal(t, "new", data["current_description"])
+		})
+
+		t.Run("POST enabled "+tc.decoded, func(t *testing.T) {
+			ctrl := newCtrl()
+			server := NewServer(ctrl, zap.NewNop().Sugar(), nil)
+			req := httptest.NewRequest(http.MethodPost, "/api/v1/servers/github/tools/"+tc.encoded+"/enabled",
+				bytes.NewBufferString(`{"enabled":false}`))
+			req.Header.Set("X-API-Key", "test-key")
+			w := httptest.NewRecorder()
+			server.ServeHTTP(w, req)
+
+			require.Equal(t, http.StatusOK, w.Code, "body=%s", w.Body.String())
+			assert.Equal(t, tc.decoded, ctrl.setToolEnabledTool)
+		})
+	}
+}