What is the client id in the mcp server config?

[agn-7]

In this MCP server config, I see a client ID attribute and its value:

https://github.com/slackapi/slack-mcp-plugin/blob/b647da95db3920c5e2ca69d39de5627766296bab/mcp.json

I guess it is related to the Cursor, not sure.

My main question is, how can I add this MCP server into my agent app, not Cursor or Claude Code? is it possible?

[WilliamBergamin]

Hi @agn-7 thanks for the question 💯

The clientId in the config is a Slack OAuth application client ID, specifically for the Claude and Cursor Slack app

My main question is, how can I add this MCP server into my agent app, not Cursor or Claude Code? is it possible?

Yess it is, we are currently working on sample apps to showcase how to do this, this documentation should also be helpful to you. In short your agent app will need to implement an OAuth flow to collect user tokens and use those to interact with the MCP server

[agn-7]

@WilliamBergamin Thanks for your response.

On Friday, I did an experiment. My MCP client already had OAuth2 support, and I tried to pretend my agent is Claude Code to use their Slack Client ID and spin up a localhost callback URI with the same 3118 port like Claude Code's Slack MCP server configuration, it worked! But at the end of the messages in Slack, it is mentioned: "Sent Using Claude".

Then, to prevent this and to have this feature genuinely for my agent, I created a Slack App with a specific APP Manifest and enabled the Model Context Protocol support toggle to have my own Client ID. However, during the OAuth2 authorization, it needed the Client Secret as well, so I had to add the Client Secret to my Slack MCP server configuration. I am not sure if I am on the right track or not, because I don't see such a thing in Cursor or Claude Code's Slack MCP server configuration.

[WilliamBergamin]

We've actually made some samples that use the MCP server public last week, they might be able to help you

• https://github.com/slack-samples/bolt-python-support-agent
• https://github.com/slack-samples/bolt-python-starter-agent
• https://github.com/slack-samples/bolt-js-support-agent
• https://github.com/slack-samples/bolt-js-starter-agent

Let me know if you find these helpful, they are also open sourced feel free to open an issue if you find something could be improved

[agn-7]

Hmm, not sure, I should review them, and don't know what bolt refers to.

Anyway, I think I handled the issue as I mentioned above, but the only difference and uncertainty is that I am using Client Secret alongside the Client ID as opposed to Cursor and Claude Code.