docs: highlight Slack MCP Server support in READMEs

Author: mwbrooks

README.md

@@ -28,6 +28,10 @@ Behind the scenes, Casey has access to five simulated tools: knowledge base sear
 
 > **Note:** All tools return simulated data for demonstration purposes. In a production app, these would connect to your actual IT systems.
 
+### Slack MCP Server
+
+Casey also works with the [Slack MCP Server](https://docs.slack.dev/agents-ai/model-context-protocol), giving it the ability to search messages and files, read channel history and threads, send messages, schedule messages, and create or update Slack canvases. When deployed with OAuth (HTTP mode), Casey automatically connects to the Slack MCP Server using the user's token, unlocking these capabilities on top of the built-in IT tools.
+
 ## Local Development
 
 This repo uses a vendored (pre-release) build of `slack-bolt` from the [bolt-python](https://github.com/slackapi/bolt-python) `main` branch. The `.whl` file lives in `vendor/` and is referenced by each app's `requirements.txt`.

claude-agent-sdk/README.md

@@ -22,6 +22,10 @@ Casey uses five simulated tools to assist users:
 
 > **Note:** All tools return simulated data for demonstration purposes. In a production app, these would connect to your actual IT systems.
 
+### Slack MCP Server
+
+Casey also works with the [Slack MCP Server](https://docs.slack.dev/agents-ai/model-context-protocol), giving it the ability to search messages and files, read channel history and threads, send messages, schedule messages, and create or update Slack canvases. When deployed with OAuth (HTTP mode), Casey automatically connects to the Slack MCP Server using the user's token, unlocking these capabilities on top of the built-in IT tools.
+
 ## Setup
 
 Before getting started, make sure you have a development workspace where you have permissions to install apps.

openai-agents-sdk/README.md

@@ -22,6 +22,10 @@ Casey uses five simulated tools to assist users:
 
 > **Note:** All tools return simulated data for demonstration purposes. In a production app, these would connect to your actual IT systems.
 
+### Slack MCP Server
+
+Casey also works with the [Slack MCP Server](https://docs.slack.dev/agents-ai/model-context-protocol), giving it the ability to search messages and files, read channel history and threads, send messages, schedule messages, and create or update Slack canvases. When deployed with OAuth (HTTP mode), Casey automatically connects to the Slack MCP Server using the user's token, unlocking these capabilities on top of the built-in IT tools.
+
 ## Setup
 
 Before getting started, make sure you have a development workspace where you have permissions to install apps.

pydantic-ai/README.md

@@ -22,6 +22,10 @@ Casey uses five simulated tools to assist users:
 
 > **Note:** All tools return simulated data for demonstration purposes. In a production app, these would connect to your actual IT systems.
 
+### Slack MCP Server
+
+Casey also works with the [Slack MCP Server](https://docs.slack.dev/agents-ai/model-context-protocol), giving it the ability to search messages and files, read channel history and threads, send messages, schedule messages, and create or update Slack canvases. When deployed with OAuth (HTTP mode), Casey automatically connects to the Slack MCP Server using the user's token, unlocking these capabilities on top of the built-in IT tools.
+
 ## Setup
 
 Before getting started, make sure you have a development workspace where you have permissions to install apps.