diff --git a/pyproject.toml b/pyproject.toml
index 9aeed2c..2c86f64 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -17,10 +17,12 @@ typer = "^0.9.0"
 rich = "^13.7.0"
 aiohttp = "^3.9.1"
 tenacity = "^8.2.3"
+anthropic = { version = "^0.18.1", optional = true }
+xmltodict = { version = "^0.13.0", optional = true }
 
-[tool.poetry.group.anthropic.dependencies]
-anthropic = "^0.18.1"
-xmltodict = "^0.13.0"
+
+[tool.poetry.extras]
+anthropic = ["anthropic", "xmltodict"]
 
 [tool.poetry.scripts]
 instructor = "instructor.cli.cli:app"