This is a mess—it's literally a repo of my ~/.claude directory. Not everything is actively used, but a good place to get inspiration is from the /agents, /commands, and /output-styles directories.
You may notice I have an agents-library and an mcp-library too—those are because I have a custom slash command that installs agents and mcps into my local project (/init-workspace).
Also, I highly recommend you check out my mcp boilerplate repo. It'll make it a lot easier to spin up new MCPs, and it has all the commands for local installation (or to your mcp-library directory lol).
The directories in here you don't recognize (/templates, /docs) are also places where I reference files in slashcommands or in system prompts, so claude can look them up when claude needs to get more information on a topic.