diff --git a/.gitignore b/.gitignore
index f117763..dfd8b34 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+.coverage
 .env
 .tox
 *.pyc
diff --git a/lib/lsp-devtools/lsp_devtools/agent/client.py b/lib/lsp-devtools/lsp_devtools/agent/client.py
index 5fccd28..e91d916 100644
--- a/lib/lsp-devtools/lsp_devtools/agent/client.py
+++ b/lib/lsp-devtools/lsp_devtools/agent/client.py
@@ -6,26 +6,27 @@
 from pygls.client import Client
 from pygls.client import aio_readline
 from pygls.protocol import default_converter
-from websockets.client import WebSocketClientProtocol
 
 from lsp_devtools.agent.protocol import AgentProtocol
 
+# from websockets.client import WebSocketClientProtocol
 
-class WebSocketClientTransportAdapter:
-    """Protocol adapter for the WebSocket client interface."""
 
-    def __init__(self, ws: WebSocketClientProtocol, loop: asyncio.AbstractEventLoop):
-        self._ws = ws
-        self._loop = loop
+# class WebSocketClientTransportAdapter:
+#     """Protocol adapter for the WebSocket client interface."""
 
-    def close(self) -> None:
-        """Stop the WebSocket server."""
-        print("-- CLOSING --")
-        self._loop.create_task(self._ws.close())
+#     def __init__(self, ws: WebSocketClientProtocol, loop: asyncio.AbstractEventLoop):
+#         self._ws = ws
+#         self._loop = loop
 
-    def write(self, data: Any) -> None:
-        """Create a task to write specified data into a WebSocket."""
-        asyncio.ensure_future(self._ws.send(data))
+#     def close(self) -> None:
+#         """Stop the WebSocket server."""
+#         print("-- CLOSING --")
+#         self._loop.create_task(self._ws.close())
+
+#     def write(self, data: Any) -> None:
+#         """Create a task to write specified data into a WebSocket."""
+#         asyncio.ensure_future(self._ws.send(data))
 
 
 class AgentClient(Client):
diff --git a/lib/lsp-devtools/lsp_devtools/record/formatters.py b/lib/lsp-devtools/lsp_devtools/record/formatters.py
index 0a9ee48..d8cb5cb 100644
--- a/lib/lsp-devtools/lsp_devtools/record/formatters.py
+++ b/lib/lsp-devtools/lsp_devtools/record/formatters.py
@@ -155,7 +155,7 @@ class FormatString:
     VARIABLE = re.compile(r"{\.([^}]+)}")
 
     def __init__(self, pattern: str):
-        self.pattern = pattern.replace("\\n", "\n").replace("\\t", "\t")
+        self.pattern = pattern  # .replace("\\n", "\n").replace("\\t", "\t")
         self._parse()
 
     def _parse(self):
diff --git a/lib/lsp-devtools/pyproject.toml b/lib/lsp-devtools/pyproject.toml
index 8677817..7bd8185 100644
--- a/lib/lsp-devtools/pyproject.toml
+++ b/lib/lsp-devtools/pyproject.toml
@@ -42,10 +42,6 @@ dev = [
     "pre-commit",
     "tox",
 ]
-test=[
-    "pytest-cov",
-    "pytest-timeout",
-]
 typecheck=[
     "mypy",
     "importlib_resources",
@@ -60,6 +56,14 @@ lsp-devtools = "lsp_devtools.cli:main"
 [tool.setuptools.packages.find]
 include = ["lsp_devtools*"]
 
+[tool.coverage.run]
+source_pkgs = ["lsp_devtools"]
+
+[tool.coverage.report]
+show_missing = true
+skip_covered = true
+sort = "Cover"
+
 [tool.isort]
 force_single_line = true
 profile = "black"
@@ -100,16 +104,3 @@ showcontent = true
 directory = "misc"
 name = "Misc"
 showcontent = true
-
-[tool.tox]
-legacy_tox_ini = """
-[tox]
-isolated_build = True
-skip_missing_interpreters = true
-envlist = py{37,38,39,310,311}
-
-[testenv]
-extras=test
-commands =
-    pytest {posargs}
-"""
diff --git a/lib/lsp-devtools/tests/record/test_formatters.py b/lib/lsp-devtools/tests/record/test_formatters.py
index d6e6ca7..c6f7066 100644
--- a/lib/lsp-devtools/tests/record/test_formatters.py
+++ b/lib/lsp-devtools/tests/record/test_formatters.py
@@ -27,7 +27,7 @@
                     "textDocument": {"uri": "file:///path/to/file.txt"},
                 },
             },
-            "textDocument/completion file:///path/to/file.txt:{'line': 1, 'character': 2}",  # noqa: E501
+            'textDocument/completion file:///path/to/file.txt:{\n  "line": 1,\n  "character": 2\n}',  # noqa: E501
         ),
         (
             "{.method} {.params.textDocument.uri}:{.params.position|Position}",
@@ -61,7 +61,7 @@
                     "items": [{"label": "one"}, {"label": "two"}, {"label": "three"}]
                 }
             },
-            "{'label': 'one'}\n{'label': 'two'}\n{'label': 'three'}",
+            '{\n  "label": "one"\n}\n{\n  "label": "two"\n}\n{\n  "label": "three"\n}',
         ),
         (
             "{.result.items[].label}",
@@ -88,7 +88,7 @@
                     "items": [{"label": "one"}, {"label": "two"}, {"label": "three"}]
                 }
             },
-            "{'label': 'one'}",
+            '{\n  "label": "one"\n}',
         ),
         (
             "{.result.items[-1]}",
@@ -97,7 +97,7 @@
                     "items": [{"label": "one"}, {"label": "two"}, {"label": "three"}]
                 }
             },
-            "{'label': 'three'}",
+            '{\n  "label": "three"\n}',
         ),
         (
             "- {.result.items[0].label}",
diff --git a/lib/lsp-devtools/tox.ini b/lib/lsp-devtools/tox.ini
new file mode 100644
index 0000000..223b1c1
--- /dev/null
+++ b/lib/lsp-devtools/tox.ini
@@ -0,0 +1,21 @@
+[tox]
+isolated_build = True
+skip_missing_interpreters = true
+min_version = 4.0
+envlist = py{38,39,310,311}
+
+[testenv]
+description = "Run lsp-devtools' test suite"
+package = wheel
+wheel_build_env = .pkg
+deps =
+     coverage[toml]
+     pytest
+
+     git+https://github.com/openlawlibrary/pygls
+commands_pre =
+    coverage erase
+commands =
+    coverage run -m pytest {posargs}
+commands_post =
+    coverage report