There is at least one MCP server in Obsidian's community plugins, plus the REST API access capability which is already addressed in several open source MCP plugins.

I use Obsidian as a persistent context store and knowledge graph (..loosely defined, i.e. link/back-link) for both Claude Code and Hermes, while also using it to generate live Wiki pages for working documentation. The native replication and the Git integrations work well keeping it all synchronized across multiple harnesses, as well. I use the native MCP server mentioned above, plus just letting the agent work with the markdown files directly.

That said, having built out all of this manually I'm excited to try out something that addresses much of this out of the box. I'd also be curious about the integration with Hermes/OpenClaw/etc.