Congrats on the launch. The arc you describe — fine-tuning, then tool-calling, then MCP, each one still "too static" — tracks with what's happened across the whole PKM space, not just agent tooling. But I'd push on one thing: MCP didn't fail because the protocol is weak, it's that access to context and surfacing of context are two different problems. An agent with MCP still has to decide to ask, at the right moment, in the right words. That's the same gap that's plagued Obsidian/Notion-style PKM forever — the archive is complete, but retrieval is still pull-based, so it only helps you when you remember to go looking.
The systems that actually feel like a second brain flip that: they push relevant history, decisions, and prior context at you before you ask, and — this part matters more than people give it credit for — they show their work. Cite where a given answer came from (which note, which meeting, which thread), not just serve up a synthesized blob. Looking at the pushback in this thread (the harvesting claim, the "zero chance I trust cloud SaaS" comments), I don't think that's really an objection to always-on capture — it's an objection to opacity. People will tolerate a lot of passive collection if they can see the receipts on what it's doing with it and where an answer traces back to. Local-only storage helps with the trust problem, but provenance is what actually earns it over time.
The systems that actually feel like a second brain flip that: they push relevant history, decisions, and prior context at you before you ask, and — this part matters more than people give it credit for — they show their work. Cite where a given answer came from (which note, which meeting, which thread), not just serve up a synthesized blob. Looking at the pushback in this thread (the harvesting claim, the "zero chance I trust cloud SaaS" comments), I don't think that's really an objection to always-on capture — it's an objection to opacity. People will tolerate a lot of passive collection if they can see the receipts on what it's doing with it and where an answer traces back to. Local-only storage helps with the trust problem, but provenance is what actually earns it over time.