Document muxing filter rules (#87)

* Add muxing filter rules

* Update changelog

* Add conversation summary note

Author: danbarr

docs/about/changelog.md

@@ -13,6 +13,11 @@ Major features and changes are noted here. To review all updates, see the
 
 Related: [Upgrade CodeGate](../how-to/install.md#upgrade-codegate)
 
+- **Muxing filter rules** - 18 Feb, 2025\
+  CodeGate v0.1.23 adds filter rules for model muxing, allowing you to define
+  which model should be used for a given file type. See the
+  [model muxing docs](../features/muxing.mdx) for more.
+
 - **PII redaction:** - 10 Feb, 2025\
   Starting with v0.1.18, CodeGate now redacts personally identifiable
   information (PII) found in LLM prompts and context. See the
@@ -21,7 +26,7 @@ Related: [Upgrade CodeGate](../how-to/install.md#upgrade-codegate)
 - **Model muxing** - 7 Feb, 2025\
   With CodeGate v0.1.17 you can use the new `/v1/mux` endpoint to configure
   model selection based on your workspace! Learn more in the
-  [model muxing guide](../features/muxing.md).
+  [model muxing guide](../features/muxing.mdx).
 
 - **OpenRouter endpoint** - 7 Feb, 2025\
   CodeGate v0.1.17 adds a dedicated `/openrouter` provider endpoint for

docs/features/muxing.md docs/features/muxing.mdxdocs/features/muxing.md renamed to docs/features/muxing.mdx

@@ -1,8 +1,11 @@
 ---
 title: Model muxing
-description: Configure a per-workspace LLM
+description: Pick the right LLM for the job
 ---
 
+import useBaseUrl from '@docusaurus/useBaseUrl';
+import ThemedImage from '@theme/ThemedImage';
+
 ## Overview
 
 _Model muxing_ (or multiplexing), allows you to configure your AI assistant once
@@ -11,12 +14,13 @@ and models without reconfiguring your development environment. This feature is
 especially useful when you're working on multiple projects or tasks that require
 different AI models.
 
-For each CodeGate workspace, you can select the AI provider and model
-combination you want to use. Then, configure your AI coding tool to use the
+In each of your CodeGate workspaces, you can select the AI provider and model
+combinations to use, even dynamically switching the active model based on file
+types found in your prompt. Then, configure your AI coding tool to use the
 CodeGate muxing endpoint `http://localhost:8989/v1/mux` as an OpenAI-compatible
 API provider.
 
-To change the model currently in use, simply switch your active CodeGate
+To change the model(s) currently in use, simply switch your active CodeGate
 workspace.
 
 ```mermaid
@@ -44,6 +48,9 @@ flowchart LR
 - You have a project that requires a specific model for a particular task, but
   you also need to switch between different models during the course of your
   work.
+- You're working in a monorepo with several different languages/file types and
+  want to dynamically switch to an optimal model as you move between different
+  parts of the codebase.
 - You want to experiment with different LLM providers and models without having
   to reconfigure your AI assistant/agent every time you switch.
 - Your AI coding assistant doesn't support a particular provider or model that
@@ -58,7 +65,7 @@ flowchart LR
 ## Configure muxing
 
 To use muxing with your AI coding assistant, you need to add one or more AI
-providers to CodeGate, then select the model you want to use on a workspace.
+providers to CodeGate, then select the model(s) you want to use on a workspace.
 
 CodeGate supports the following LLM providers for muxing:
 
@@ -93,13 +100,47 @@ For locally-hosted models, you must use `http://host.docker.internal` instead of
 
 :::
 
-### Select the model for a workspace
+### Configure workspace models
 
 Open the settings of one of your [workspaces](./workspaces.mdx) from the
-Workspace selection menu or the
+workspace selection menu or the
 [Manage Workspaces](http://localhost:9090/workspaces) screen.
 
-In the **Preferred Model** section, select the model to use with the workspace.
+In the **Model Muxing** section, select the default ("catch-all") model to use
+with the workspace.
+
+To assign a different model based on filename, click **Add Filter**. In the
+**Filter by** column, enter a file name or extension string to match. This is a
+simple substring match, wildcards are not supported. For example, to match
+Python files, enter `.py`. Then select the model to use with that file type.
+
+Filter rules are evaluated top-down. CodeGate selects the active model for a
+request using the first matching rule. If the prompt contains multiple files in
+context, the first rule that matches _any_ of the files is used. If no filter is
+matched, the catch-all rule applies.
+
+<ThemedImage
+  alt='An example showing several muxing rules for different file types'
+  sources={{
+    light: useBaseUrl('/img/features/muxing-rules-light.webp'),
+    dark: useBaseUrl('/img/quickstart/muxing-rules-dark.webp'),
+  }}
+  title='Example muxing rules'
+  width={'800px'}
+/>
+_An example showing several muxing rules for different file types_
+
+Breaking down the above example:
+
+- Markdown files (`.md`) use the gpt-4o-mini model from the OpenAI provider.
+- JavaScript and TypeScript files (`.js` and `.ts`, which also matches `.jsx`
+  and `.tsx`) use anthropic/claude-3.5-sonnet via OpenRouter.
+- All other requests use Ollama.
+- A request containing both a JavaScript and Markdown file will match the `.md`
+  rule first and use OpenAI.
+
+You can validate which provider was used for a given request by checking the
+**conversation summary** in the CodeGate dashboard.
 
 ### Manage existing providers
 

docs/features/workspaces.mdx

@@ -27,7 +27,7 @@ Workspaces offer several key features:
   for different types of tasks. Choose from CodeGate's library of community
   prompts or create your own.
 
-- [**Model muxing**](./muxing.md): Configure the LLM provider/model for each
+- [**Model muxing**](./muxing.mdx): Configure the LLM provider/model for each
   workspace, allowing you to configure your AI assistant/agent once and switch
   between different models on the fly. This is useful when working on multiple
   projects or tasks that require different AI models.
@@ -115,7 +115,7 @@ In the workspace list, open the menu (**...**) next to a workspace to
 **Activate**, **Edit**, or **Archive** the workspace.
 
 **Edit** opens the workspace settings page. From here you can rename the
-workspace, select the LLM provider and model (see [Model muxing](./muxing.md)),
+workspace, select the LLM provider and model (see [Model muxing](./muxing.mdx)),
 set the custom prompt instructions, or archive the workspace.
 
 **Archived** workspaces can be restored or permanently deleted from the

docs/index.md

@@ -41,7 +41,7 @@ efficiency, including:
   information
 - [Dependency risk awareness](./features/dependency-risk.md) to update the LLM's
   knowledge of malicious or deprecated open source packages
-- [Model muxing](./features/muxing.md) to quickly select the best LLM
+- [Model muxing](./features/muxing.mdx) to quickly select the best LLM
   provider/model for your current task
 - [Workspaces](./features/workspaces.mdx) to organize and customize your LLM
   interactions

docs/integrations/aider.mdx

@@ -17,7 +17,7 @@ CodeGate works with the following AI model providers through aider:
 - Hosted:
   - [OpenAI](https://openai.com/api/) and OpenAI-compatible APIs
 
-You can also configure [CodeGate muxing](../features/muxing.md) to select your
+You can also configure [CodeGate muxing](../features/muxing.mdx) to select your
 provider and model using [workspaces](../features/workspaces.mdx).
 
 :::note

docs/integrations/avante.mdx

@@ -65,7 +65,7 @@ server.
 
 ### Model muxing
 
-To take advantage of CodeGate's [model muxing feature](../features/muxing.md),
+To take advantage of CodeGate's [model muxing feature](../features/muxing.mdx),
 use **avante.nvim**'s OpenAI provider with the following configuration:
 
 ```lua

docs/integrations/cline.mdx

@@ -21,7 +21,7 @@ CodeGate works with the following AI model providers through Cline:
   - [OpenAI](https://openai.com/api/) and compatible APIs
   - [OpenRouter](https://openrouter.ai/)
 
-You can also configure [CodeGate muxing](../features/muxing.md) to select your
+You can also configure [CodeGate muxing](../features/muxing.mdx) to select your
 provider and model using [workspaces](../features/workspaces.mdx).
 
 ## Install the Cline extension

docs/integrations/continue.mdx

@@ -25,7 +25,7 @@ CodeGate works with the following AI model providers through Continue:
   - [OpenAI](https://openai.com/api/)
   - [OpenRouter](https://openrouter.ai/)
 
-You can also configure [CodeGate muxing](../features/muxing.md) to select your
+You can also configure [CodeGate muxing](../features/muxing.mdx) to select your
 provider and model using [workspaces](../features/workspaces.mdx).
 
 ## Install the Continue plugin
@@ -129,7 +129,7 @@ to the pre-release version (v0.9.x) of the Continue extension.
 
 :::
 
-First, configure your [provider(s)](../features/muxing.md#add-a-provider) and
+First, configure your [provider(s)](../features/muxing.mdx#add-a-provider) and
 select a model for each of your
 [workspace(s)](../features/workspaces.mdx#manage-workspaces) in the CodeGate
 dashboard.

docs/integrations/kodu.mdx

@@ -14,7 +14,7 @@ take their project from idea to execution.
 
 CodeGate supports OpenAI-compatible APIs and OpenRouter with Claude Coder.
 
-You can also configure [CodeGate muxing](../features/muxing.md) to select your
+You can also configure [CodeGate muxing](../features/muxing.mdx) to select your
 provider and model using [workspaces](../features/workspaces.mdx).
 
 ## Install the Claude Coder extension

docs/integrations/open-interpreter.mdx

@@ -14,7 +14,7 @@ LLMs run code locally through a ChatGPT-like interface in your terminal.
 CodeGate works with [OpenAI](https://openai.com/api/) and compatible APIs
 through Open Interpreter.
 
-You can also configure [CodeGate muxing](../features/muxing.md) to select your
+You can also configure [CodeGate muxing](../features/muxing.mdx) to select your
 provider and model using [workspaces](../features/workspaces.mdx).
 
 :::note
@@ -33,7 +33,7 @@ set to CodeGate's local API port, `http://localhost:8989/<provider>`.
 
 <Tabs groupId="provider" queryString="provider">
 <TabItem value="mux" label="CodeGate muxing" default>
-First, configure your [provider(s)](../features/muxing.md#add-a-provider) and
+First, configure your [provider(s)](../features/muxing.mdx#add-a-provider) and
 select a model for each of your
 [workspace(s)](../features/workspaces.mdx#manage-workspaces) in the CodeGate dashboard.