Durable Harn session-store primitive.
One source of truth for persisted agent/session events (Message,
ToolCall, ToolResult, Plan, Compaction, SystemReminder,
Hypothesis, Receipt, Reminder, PermissionDecision, plus
arbitrary Custom shapes), snapshots, replay, fork/truncate, signed
receipts (Ed25519 over canonical JSON), and retention. Server and host
adapters can layer transport, auth, and product policy on top without
reimplementing transcript storage semantics.
Layout
- [
event] - event taxonomy and canonical JSON encoder - [
signing] - Ed25519 chain hashes and receipt signatures - [
store] - publicSessionStoretrait and shared types - [
memory] - in-memory backend for tests and headless dev - [
sqlite] - persistent SQLite backend for local/self-hosted use - [
retention] - declarative per-tenant retention policy