diff --git a/README.md b/README.md
index e877ad460..b6c60ebb8 100644
--- a/README.md
+++ b/README.md
@@ -1,13 +1,15 @@
 
 # aider is AI pair programming in your terminal
 
-Aider is a command line tool that lets you pair program with GPT-3.5/GPT-4,
+Aider is a command line tool that lets you pair program with LLMs,
 to edit code stored in your local git repository.
 Aider will directly edit the code in your local source files,
 and [git commit the changes](https://aider.chat/docs/faq.html#how-does-aider-use-git)
 with sensible commit messages.
 You can start a new project or work with an existing git repo.
 Aider is unique in that it lets you ask for changes to [pre-existing, larger codebases](https://aider.chat/docs/repomap.html).
+Aider works well with GPT 3.5, GPT-4, GPT-4 Turbo with Vision,
+Claude 3 Opus and has support for connecting to almost any LLM.
 
 <p align="center">
   <img src="assets/screencast.svg" alt="aider screencast">
diff --git a/_posts/2024-03-08-claude-3.md b/_posts/2024-03-08-claude-3.md
index 0a991729a..b1ed14a29 100644
--- a/_posts/2024-03-08-claude-3.md
+++ b/_posts/2024-03-08-claude-3.md
@@ -15,19 +15,12 @@ using Aider's code editing benchmark suite.
 Claude 3 Opus outperforms all of OpenAI's models,
 making it the best available model for pair programming with AI.
 
-Aider currently supports Claude 3 Opus via
-[OpenRouter](https://aider.chat/docs/faq.html#accessing-other-llms-with-openrouter):
+To use Claude 3 Opus with aider:
 
 ```
-# Install aider
 pip install aider-chat
-
-# Setup OpenRouter access
-export OPENAI_API_KEY=<your-openrouter-key>
-export OPENAI_API_BASE=https://openrouter.ai/api/v1
-
-# Run aider with Claude 3 Opus using the diff editing format
-aider --model anthropic/claude-3-opus --edit-format diff
+export ANTHROPIC_API_KEY=sk-...
+aider --opus
 ```
 
 ## Aider's code editing benchmark
diff --git a/aider/main.py b/aider/main.py
index 765f35900..61c76a8d6 100644
--- a/aider/main.py
+++ b/aider/main.py
@@ -170,6 +170,14 @@ def main(argv=None, input=None, output=None, force_git_root=None):
         default=default_model,
         help=f"Specify the model to use for the main chat (default: {default_model})",
     )
+    opus_model = "claude-3-opus-20240229"
+    core_group.add_argument(
+        "--opus",
+        action="store_const",
+        dest="model",
+        const=opus_model,
+        help=f"Use {opus_model} model for the main chat",
+    )
     default_4_model = "gpt-4-0613"
     core_group.add_argument(
         "--4",
@@ -238,13 +246,6 @@ def main(argv=None, input=None, output=None, force_git_root=None):
         env_var="OPENAI_ORGANIZATION_ID",
         help="Specify the OpenAI organization ID",
     )
-    model_group.add_argument(
-        "--openrouter",
-        dest="openai_api_base",
-        action="store_const",
-        const="https://openrouter.ai/api/v1",
-        help="Specify the api base url as https://openrouter.ai/api/v1",
-    )
     model_group.add_argument(
         "--edit-format",
         metavar="EDIT_FORMAT",
diff --git a/aider/models.py b/aider/models.py
index a45f3b977..bd48d486b 100644
--- a/aider/models.py
+++ b/aider/models.py
@@ -101,7 +101,7 @@ MODEL_SETTINGS = [
     # Claude
     ModelSettings(
         "claude-3-opus-20240229",
-        "udiff",
+        "diff",
         weak_model_name="claude-3-haiku-20240307",
         use_repo_map=True,
         send_undo_reply=True,