Support NERV CLI as optional alternative to Obsidian MCP for vault operations

[jdidion]

Motivation

obsidian-nerv provides typed ontology, write-time validation, and bidirectional relationship enforcement for Obsidian vaults. It uses Obsidian CLI (IPC) rather than MCP.

Curaitor currently uses Obsidian MCP for all vault operations. Adding NERV CLI as an optional backend would enable:

• Typed ontology: notes declare types (ROOT, LEAF, ONTOLOGY), relationships are bidirectional and typed
• Write-time validation: prevents broken cross-references when agents rename/move entities
• Schema enforcement: frontmatter schema validated before writes complete
• Pre-synthesized structure: typed frontmatter IS the compiled knowledge (see Pre-synthesized content and typed ontology for curaitor knowledge base #1)

Architecture

NERV's adapter pattern (VaultOps interface) already decouples from Obsidian CLI:

Agent Intent → NERV CLI → VaultOps Interface → Obsidian CLI (IPC) → Obsidian Runtime

Curaitor could route vault operations through NERV when available:

Curaitor skill → NERV CLI (if installed) → VaultOps → Obsidian
                 OR
Curaitor skill → Obsidian MCP (fallback)

Requirements

• NERV CLI: macOS, Bun runtime, Obsidian ≥ 1.12.4 with CLI enabled
• Filed MCP support request on NERV repo — if they add MCP adapter, curaitor wouldn't need to call NERV CLI directly

Implementation

1. Add optional vault_backend: mcp|nerv to config/user-settings.yaml
2. Wrap vault operations (read, write, search, move, delete) in an abstraction that routes to MCP or NERV
3. When NERV is available, use its validation and typed ontology
4. Fallback gracefully to MCP when NERV is not installed

Related

• Pre-synthesized content and typed ontology for curaitor knowledge base #1 Pre-synthesized content and typed ontology
• obsidian-nerv
• NERV MCP support issue