diff --git a/Gemfile b/Gemfile
index 454fb24..d553644 100644
--- a/Gemfile
+++ b/Gemfile
@@ -9,5 +9,3 @@ gem "rake", "~> 13.0"
 gem "irb"
 
 gem "test-unit", "~> 3.0"
-
-gem "ruby-lsp"
diff --git a/Gemfile.lock b/Gemfile.lock
index 1efc807..f2b477b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -9,19 +9,10 @@ GEM
     io-console (0.6.0)
     irb (1.6.2)
       reline (>= 0.3.0)
-    language_server-protocol (3.17.0.3)
     power_assert (2.0.2)
-    prettier_print (1.2.0)
     rake (13.0.6)
     reline (0.3.2)
       io-console (~> 0.5)
-    ruby-lsp (0.3.8)
-      language_server-protocol (~> 3.17.0)
-      sorbet-runtime
-      syntax_tree (>= 5.0.0, < 6)
-    sorbet-runtime (0.5.10648)
-    syntax_tree (5.3.0)
-      prettier_print (>= 1.2.0)
     test-unit (3.5.5)
       power_assert
 
@@ -33,7 +24,6 @@ PLATFORMS
 DEPENDENCIES
   irb
   rake (~> 13.0)
-  ruby-lsp
   test-unit (~> 3.0)
   tracer!
 
diff --git a/lib/tracer/base.rb b/lib/tracer/base.rb
index 491c4f0..234c0e1 100644
--- a/lib/tracer/base.rb
+++ b/lib/tracer/base.rb
@@ -70,12 +70,21 @@ def pretty_path(path)
       end
     end
 
-    def initialize(output: STDOUT, pattern: nil, colorize: nil, depth_offset: 0)
+    attr_reader :header
+
+    def initialize(
+      output: STDOUT,
+      pattern: nil,
+      colorize: nil,
+      depth_offset: 0,
+      header: nil
+    )
       @name = self.class.name
       @type = @name.sub(/Tracer\z/, "")
       @output = output
       @depth_offset = depth_offset
       @colorize = colorize || colorizable?
+      @header = header
 
       if pattern
         @pattern = Regexp.compile(pattern)
@@ -90,10 +99,6 @@ def key
       [@type, @pattern, @into].freeze
     end
 
-    def header
-      ""
-    end
-
     def to_s
       s = "#{@name} #{description}"
       s += " with pattern #{@pattern.inspect}" if @pattern
@@ -141,10 +146,14 @@ def skip_internal?(tp)
 
     def out(tp, msg = nil, depth: caller.size - 1, location: nil)
       location ||= "#{tp.path}:#{tp.lineno}"
-      buff =
-        "#{header} \#depth:#{"%-2d" % depth}#{msg} at #{colorize("#{location}", [:GREEN])}"
+      if header
+        str = +"#{header} "
+      else
+        str = +""
+      end
+      str << "\#depth:#{"%-2d" % depth}#{msg} at #{colorize("#{location}", [:GREEN])}"
 
-      puts buff
+      puts str
     end
 
     def puts(msg)
diff --git a/test/ruby_tracer/call_tracer_test.rb b/test/ruby_tracer/call_tracer_test.rb
deleted file mode 100644
index 493c871..0000000
--- a/test/ruby_tracer/call_tracer_test.rb
+++ /dev/null
@@ -1,46 +0,0 @@
-require_relative "../test_helper"
-
-module Tracer
-  class CallTracerTest < TestCase
-    include ActivationTests
-
-    private
-
-    def build_tracer
-      CallTracer.new(output: @output)
-    end
-  end
-
-  class CallTracerIntegrationTest < IntegrationTestCase
-    def test_object_tracer_traces_method_calls
-      file = write_file("foo.rb", <<~RUBY)
-        obj = Object.new
-
-        def obj.foo
-          100
-        end
-
-        def bar(obj)
-          obj.foo
-        end
-
-        CallTracer.new.start
-
-        bar(obj)
-      RUBY
-
-      out, err = execute_file(file)
-
-      assert_empty(err)
-      assert_traces(
-        [
-          %r{#depth:0 >  Object#bar at .*/foo\.rb:13},
-          %r{#depth:1 >   #<Object:.*>\.foo at .*/foo\.rb:8},
-          %r{#depth:1 <   #<Object:.*>\.foo #=> 100 at .*/foo\.rb:8},
-          %r{#depth:0 <  Object#bar #=> 100 at .*/foo\.rb:13}
-        ],
-        out
-      )
-    end
-  end
-end
diff --git a/test/tracer/call_tracer_test.rb b/test/tracer/call_tracer_test.rb
new file mode 100644
index 0000000..3f67a6d
--- /dev/null
+++ b/test/tracer/call_tracer_test.rb
@@ -0,0 +1,77 @@
+require_relative "../test_helper"
+
+module Tracer
+  class CallTracerTest < TestCase
+    include ActivationTests
+
+    private
+
+    def build_tracer
+      CallTracer.new(output: @output)
+    end
+  end
+
+  class CallTracerIntegrationTest < IntegrationTestCase
+    def test_object_tracer_traces_method_calls
+      file = write_file("foo.rb", <<~RUBY)
+        obj = Object.new
+
+        def obj.foo
+          100
+        end
+
+        def bar(obj)
+          obj.foo
+        end
+
+        CallTracer.new.start
+
+        bar(obj)
+      RUBY
+
+      out, err = execute_file(file)
+
+      assert_empty(err)
+      assert_traces(
+        [
+          %r{^#depth:0 >  Object#bar at .*/foo\.rb:13},
+          %r{^#depth:1 >   #<Object:.*>\.foo at .*/foo\.rb:8},
+          %r{^#depth:1 <   #<Object:.*>\.foo #=> 100 at .*/foo\.rb:8},
+          %r{^#depth:0 <  Object#bar #=> 100 at .*/foo\.rb:13}
+        ],
+        out
+      )
+    end
+
+    def test_object_tracer_with_header
+      file = write_file("foo.rb", <<~RUBY)
+        obj = Object.new
+
+        def obj.foo
+          100
+        end
+
+        def bar(obj)
+          obj.foo
+        end
+
+        CallTracer.new(header: "tracer-1").start
+
+        bar(obj)
+      RUBY
+
+      out, err = execute_file(file)
+
+      assert_empty(err)
+      assert_traces(
+        [
+          %r{^tracer-1 #depth:0 >  Object#bar at .*/foo\.rb:13},
+          %r{^tracer-1 #depth:1 >   #<Object:.*>\.foo at .*/foo\.rb:8},
+          %r{^tracer-1 #depth:1 <   #<Object:.*>\.foo #=> 100 at .*/foo\.rb:8},
+          %r{^tracer-1 #depth:0 <  Object#bar #=> 100 at .*/foo\.rb:13}
+        ],
+        out
+      )
+    end
+  end
+end
diff --git a/test/ruby_tracer/exception_tracer_test.rb b/test/tracer/exception_tracer_test.rb
similarity index 56%
rename from test/ruby_tracer/exception_tracer_test.rb
rename to test/tracer/exception_tracer_test.rb
index 23be166..1f40b05 100644
--- a/test/ruby_tracer/exception_tracer_test.rb
+++ b/test/tracer/exception_tracer_test.rb
@@ -22,7 +22,20 @@ def test_exception_tracer_traces_exceptions
       out, err = execute_file(file)
 
       assert_empty(err)
-      assert_traces([/#depth:0  #<RuntimeError: boom> at .*foo.rb:3/], out)
+      assert_traces([/^#depth:0  #<RuntimeError: boom> at .*foo.rb:3/], out)
+    end
+
+    def test_exception_tracer_with_header
+      file = write_file("foo.rb", <<~RUBY)
+        ExceptionTracer.new(header: "tracer-1").start
+
+        raise "boom" rescue nil
+      RUBY
+
+      out, err = execute_file(file)
+
+      assert_empty(err)
+      assert_traces([/^tracer-1 #depth:0  #<RuntimeError: boom> at .*foo.rb:3/], out)
     end
   end
 end
diff --git a/test/ruby_tracer/helper_test.rb b/test/tracer/helper_test.rb
similarity index 100%
rename from test/ruby_tracer/helper_test.rb
rename to test/tracer/helper_test.rb
diff --git a/test/ruby_tracer/line_tracer_test.rb b/test/tracer/line_tracer_test.rb
similarity index 54%
rename from test/ruby_tracer/line_tracer_test.rb
rename to test/tracer/line_tracer_test.rb
index 6a1561e..3701130 100644
--- a/test/ruby_tracer/line_tracer_test.rb
+++ b/test/tracer/line_tracer_test.rb
@@ -23,7 +23,21 @@ def test_line_tracer_traces_line_executions
       out, err = execute_file(file)
 
       assert_empty(err)
-      assert_traces([/#depth:1  at .*foo.rb:3/, /#depth:1  at .*foo.rb:4/], out)
+      assert_traces([/^#depth:1  at .*foo.rb:3/, /#depth:1  at .*foo.rb:4/], out)
+    end
+
+    def test_line_tracer_with_header
+      file = write_file("foo.rb", <<~RUBY)
+        LineTracer.new(header: "tracer-1").start
+
+        a = 1
+        b = 2
+      RUBY
+
+      out, err = execute_file(file)
+
+      assert_empty(err)
+      assert_traces([/^tracer-1 #depth:1  at .*foo.rb:3/, /#depth:1  at .*foo.rb:4/], out)
     end
   end
 end
diff --git a/test/ruby_tracer/object_tracer_test.rb b/test/tracer/object_tracer_test.rb
similarity index 66%
rename from test/ruby_tracer/object_tracer_test.rb
rename to test/tracer/object_tracer_test.rb
index 98c2235..9c1421f 100644
--- a/test/ruby_tracer/object_tracer_test.rb
+++ b/test/tracer/object_tracer_test.rb
@@ -50,8 +50,37 @@ def bar(obj)
       assert_empty(err)
       assert_traces(
         [
-          %r{#depth:0  #<Object:.*> is used as a parameter obj of Object#bar at .*/foo\.rb:13},
-          %r{#depth:1  #<Object:.*> receives \.foo at .*/foo\.rb:8}
+          %r{^#depth:0  #<Object:.*> is used as a parameter obj of Object#bar at .*/foo\.rb:13},
+          %r{^#depth:1  #<Object:.*> receives \.foo at .*/foo\.rb:8}
+        ],
+        out
+      )
+    end
+
+    def test_object_tracer_with_header
+      file = write_file("foo.rb", <<~RUBY)
+        obj = Object.new
+
+        def obj.foo
+          100
+        end
+
+        def bar(obj)
+          obj.foo
+        end
+
+        ObjectTracer.new(obj, header: "tracer-1").start
+
+        bar(obj)
+      RUBY
+
+      out, err = execute_file(file)
+
+      assert_empty(err)
+      assert_traces(
+        [
+          %r{tracer-1 #depth:0  #<Object:.*> is used as a parameter obj of Object#bar at .*/foo\.rb:13},
+          %r{tracer-1 #depth:1  #<Object:.*> receives \.foo at .*/foo\.rb:8}
         ],
         out
       )
@@ -78,8 +107,8 @@ def bar(**kwargs)
       assert_empty(err)
       assert_traces(
         [
-          %r{#depth:0  #<Object:.*> is used as a parameter in args of Object#foo at .*/foo\.rb:11},
-          %r{#depth:0  #<Object:.*> is used as a parameter in kwargs of Object#bar at .*/foo\.rb:12}
+          %r{^#depth:0  #<Object:.*> is used as a parameter in args of Object#foo at .*/foo\.rb:11},
+          %r{^#depth:0  #<Object:.*> is used as a parameter in kwargs of Object#bar at .*/foo\.rb:12}
         ],
         out
       )
@@ -108,9 +137,9 @@ def bar(**kwargs)
       assert_empty(err)
       assert_traces(
         [
-          %r{#depth:0  #<Object:.*> is used as a parameter in args of Object#foo at .*/foo\.rb:12},
-          %r{#depth:1  #<Object:.*> is used as a parameter obj of block{} at .*/foo\.rb:4},
-          %r{#depth:2  #<Object:.*> is used as a parameter in kwargs of Object#bar at .*/foo\.rb:13}
+          %r{^#depth:0  #<Object:.*> is used as a parameter in args of Object#foo at .*/foo\.rb:12},
+          %r{^#depth:1  #<Object:.*> is used as a parameter obj of block{} at .*/foo\.rb:4},
+          %r{^#depth:2  #<Object:.*> is used as a parameter in kwargs of Object#bar at .*/foo\.rb:13}
         ],
         out
       )
@@ -138,8 +167,8 @@ def bar(obj)
       assert_empty(err)
       assert_traces(
         [
-          %r{#depth:0  #<Object:.*> is used as a parameter obj of Object#bar at .*/foo\.rb:13},
-          %r{#depth:1  #<Object:.*> receives \.foo at .*/foo\.rb:8}
+          %r{^#depth:0  #<Object:.*> is used as a parameter obj of Object#bar at .*/foo\.rb:13},
+          %r{^#depth:1  #<Object:.*> receives \.foo at .*/foo\.rb:8}
         ],
         out
       )
@@ -174,8 +203,8 @@ def test_object_tracer_works_with_nil_defined_class
       assert_empty(err)
       assert_traces(
         [
-          /#depth:-1 #<Object:.*> receives #instance_eval \(BasicObject#instance_eval\) at .*foo\.rb:4/,
-          /#depth:1  #<Object:.*> receives <eval or exec with &block> at .*foo.rb:4:in `instance_eval'/
+          /^#depth:-1 #<Object:.*> receives #instance_eval \(BasicObject#instance_eval\) at .*foo\.rb:4/,
+          /^#depth:1  #<Object:.*> receives <eval or exec with &block> at .*foo.rb:4:in `instance_eval'/
         ],
         out
       )
@@ -208,9 +237,9 @@ def bar(obj)
       assert_empty(err)
       assert_traces(
         [
-          %r{#depth:0  #<Foo.* does not have #inspect> is used as a parameter obj of Object#bar at .*/foo\.rb:17},
-          %r{#depth:1  #<Foo.* does not have #inspect> receives \.foo at .*/foo\.rb:12},
-          %r{#depth:0  #<Foo.* does not have #inspect> receives #baz \(Foo#baz\) at .*/foo\.rb:18}
+          %r{^#depth:0  #<Foo.* does not have #inspect> is used as a parameter obj of Object#bar at .*/foo\.rb:17},
+          %r{^#depth:1  #<Foo.* does not have #inspect> receives \.foo at .*/foo\.rb:12},
+          %r{^#depth:0  #<Foo.* does not have #inspect> receives #baz \(Foo#baz\) at .*/foo\.rb:18}
         ],
         out
       )