Journal substrate canon sync

PR: Journal → Substrate Canon Sync¶

Title¶

feat(journal): canonical substrate-backed journal sync with hot KV mirror

Objective¶

Make Mobius-Substrate the canonical journal memory layer and keep KV/Redis as the hot operational mirror.

Architecture Rule¶

Write Path¶

POST /api/agents/journal - validate payload - writeJournalToSubstrate() - KV mirror (optional) - return canonical result

Read Modes¶

• HOT = KV / Redis
• CANON = Substrate repo
• MERGED = KV + Substrate fallback

API Changes¶

POST /api/agents/journal¶

Success Response¶

{
  "ok": true,
  "canonical": true,
  "path": "journals/zeus/2026-04-20T09-00-00Z-journal.json",
  "mirrored_to_kv": true,
  "timestamp": "2026-04-20T09:00:00Z"
}

Failure Response¶

{
  "ok": false,
  "canonical": false,
  "error": "substrate_write_failed",
  "mirrored_to_kv": false
}

GET /api/agents/journal¶

Query params: - mode=hot|canon|merged - agent=ZEUS - cycle=C-286 - limit=10

Schema Update¶

Add optional fields: - verification_status?: "unverified" | "confirmed" | "contested" - tripwire_context?: string[] - canonical_path?: string - commit_sha?: string

Snapshot Integration¶

Support: /api/terminal/snapshot?include_substrate=true&journal_mode=merged

Example payload:

{
  "journal_mode": "merged",
  "journal_summary": {
    "latest_agent_entries": [
      {
        "agent": "zeus",
        "source": "substrate",
        "timestamp": "2026-04-20T09:00:00Z",
        "severity": "elevated",
        "summary": "Tripwire persistent; GI source live."
      }
    ]
  }
}

Substrate File Layout¶

Mobius-Substrate/
  journals/
    zeus/
    atlas/
    hermes/
    eve/

File naming: YYYY-MM-DDTHH-MM-SSZ-journal.json

Cycle Rollups¶

Mobius-Substrate/
  cycles/
    C-286/
      summary.json
      timeline.json
      journals-index.json

Integrity Rules¶

• Substrate write failure = request fails
• KV mirror failure = allowed, log only

Environment Variables¶

• SUBSTRATE_GITHUB_TOKEN=...
• JOURNAL_DEFAULT_MODE=merged
• JOURNAL_CANONICAL_REQUIRED=true
• JOURNAL_KV_MIRROR=true

UI Updates¶

Mode selector: [ HOT ] [ CANON ] [ MERGED ]

Journal card fields: - agent - timestamp - severity - source badge (KV / SUBSTRATE) - canonical path link

Tasks¶

Backend¶

• enforce canonical write
• add read modes
• extend schema
• snapshot integration

Frontend¶

• journal mode selector
• source badges
• canonical link

Reliability¶

• handle failure states
• log KV mirror failures

Acceptance Criteria¶

• all journals written to Substrate
• KV is mirror only
• read modes functional
• snapshot includes journal summary
• UI shows source
• failures handled correctly

Outcome¶

Mobius becomes a durable, replayable, substrate-backed system memory — not just a terminal feed.