Vault Steward MCP candidates

Host Adapter implementation candidates for Vault Steward. They are reusable primitives, not canonical bindings: every installer must pin, scope, smoke-test, and pass Conformance on the target host.

Both servers are zero-dependency single files (Node ≥ 18 built-ins only; paper-fetch-mcp additionally shells out to pdftotext for its PDF fallback).

Deliberate boundaries

These servers are I/O capability layers only. Verdicts, scoring, state transitions, and completion belong to the workflow's gate core, which is implemented on the host — never here.

• Reading, writing, and deleting have separate rooted or exact scopes. Unconfigured mutation surfaces are absent from tools/list.

• vault_search requires a folder scope — full-vault scans are not offered.

• todo_query returns only [ ] plus the configured exact selector and a source fingerprint. todo_transition fails closed if that source changed.

• Paths are Vault-relative and checked on resolved real paths. Default read denies cover Vault control, trash, agent configuration, and every .git directory.

• paper_fulltext_fetch does not treat metadata or an abstract as full text; it requires a retrievable arXiv, OA PDF, or structurally identified full-article HTML source.

Related MCP server: obsidian-mcp-complete

Develop

npm run smoke        # offline smoke suites for both servers
SMOKE_NETWORK=1 node tests/smoke-paper-fetch.mjs   # + arXiv, DOI, and OpenAlex ID paths
npm run pack:all     # build dist/*.tgz release assets
npm run digest       # sha256 for the release manifest

Release & install (consumed by the workflow's bootstrap)

Release assets are the npm pack tgz files plus their sha256 digests. The bootstrap installs a pinned asset — never a floating latest:

npm install --omit=dev --ignore-scripts <verified .tgz>

MCP registration example (any MCP host):

vault-workspace:
  command: node
  args: [<install path>/node_modules/vault-workspace-mcp/server.mjs]
  env:
    VAULT_PATH: /absolute/path/to/vault
    READ_ROOTS: "."
    READ_DENIES: ".obsidian,.trash,.agents,.claude,.codex,**/.git"
    WRITE_PATHS: <assignment output>   # or a Gate-owned WRITE_ROOTS
    TODO_SELECTOR: "#agent/todo"
    TODO_MARKS: "waiting=~,succeeded=/,failed=!"
    TODO_WRITE: "0"                   # only a Gate instance receives 1
paper-fetch:
  command: node
  args: [<install path>/node_modules/paper-fetch-mcp/server.mjs]