AWAY_SUMMARY digest

When the user has been silent for a configurable threshold (default 4 hours), the next inbound message triggers a short markdown digest that summarises everything the agent did during the silence: goals completed, aborts, failures, and turn counts. Default is disabled — per-binding opt-in.

Why

In assistant mode, the agent runs proactively in the user's absence. When the user comes back to the chat, they need a quick recap before the agent processes their new request. AWAY_SUMMARY is that recap.

The digest answers "what did you do while I was gone?" with a few counter bullets, NOT a long narrative. If you want a richer LLM-summarised version (1–3 sentences of natural prose), that's the deferred 80.14.b follow-up.

Configuration

agents:
  - id: kate
    away_summary:
      enabled: true
      threshold_hours: 4    # default
      max_events: 50        # default

Field	Type	Default	Notes
`enabled`	bool	`false`	Master toggle
`threshold_hours`	u64	`4`	Hours of silence before next inbound triggers digest. `0` would fire on every inbound — operator-side rate limiting becomes their responsibility. Rejected at validate time when > 30 days (likely operator confusion).
`max_events`	usize	`50`	Cap on events included in the digest. Larger windows still fire but truncate with a `(showing the most recent N — older events may exist)` suffix. Rejected at validate time when 0.

Output shape

Template-based markdown (no LLM call in the slim MVP — pure-fn render):

**While you were away** (last 6h12m):
- 7 goal turn(s) recorded
- 4 completed
- 1 aborted/cancelled
- 1 failed
- 1 in progress / other

When the event count hits max_events, a truncation suffix is appended:

_(showing the most recent 50 — older events may exist)_

Wiring (operator-side)

Today's slim MVP ships the digest helper as a pure-async function in nexo-dispatch-tools::away_summary:

#![allow(unused)]
fn main() {
use nexo_dispatch_tools::try_compose_away_digest;

// Inbound handler — called when a new user message arrives.
let digest = try_compose_away_digest(
    &cfg.away_summary.unwrap_or_default(),
    last_seen,           // Option<DateTime<Utc>> from caller storage
    chrono::Utc::now(),
    turn_log_store.as_ref(),
).await?;

if let Some(text) = digest {
    // Deliver via notify_origin BEFORE processing the user inbound.
    notify_origin(channel, &text).await?;
}

// Atomically update last_seen = now after composing
// (caller-managed storage — pairing store, separate SQLite, in-memory map).
update_last_seen(channel, sender_id, chrono::Utc::now()).await?;

// Now process the user's actual message.
process_inbound(...).await?;
}

The helper walks 4 gates cheapest-first:

cfg.enabled (opt-in)
last_seen.is_some() — None returns None without firing so the caller can use it as the bootstrap path (set last_seen = now without burning the threshold)
now - last_seen >= threshold — negative elapsed (clock skew) returns None
Turn-log has at least one event since last_seen — empty digest is not worth sending

When all four pass, returns Some(markdown).

Atomic update pattern

The last_seen storage is operator-managed in the slim MVP: the helper accepts the timestamp as a parameter, doesn't couple to nexo-pairing or any specific table. Whatever you choose, update it atomically AFTER composing the digest so a rapid double-inbound doesn't fire twice.

Defense-in-depth

Edge case	Behaviour
`enabled: false`	Returns None
`last_seen: None` (bootstrap)	Returns None — caller sets last_seen without firing
`now - last_seen < threshold`	Returns None
`now < last_seen` (clock skew)	Returns None
Turn-log empty	Returns None
`max_events == 0`	Validate rejects at boot (not at runtime)
`threshold_hours > 30 days`	Validate rejects at boot

Deferred follow-ups

80.14.b — LLM-summarised version: forks a subagent that takes the events list and renders a 1–3 sentence prose summary. Today's MVP is template-based.
80.14.c — last_seen_at tracking in nexo-pairing::PairingStore with SQLite migration so operators don't roll their own.
80.14.d — Per-channel-adapter rendering (whatsapp / telegram render markdown differently).
80.14.e — Time-of-day awareness ("don't ping at 3am unless awake_hours covers").
80.14.f — Custom prompt template per agent (relevant once 80.14.b ships).
80.14.g — main.rs inbound interceptor wire (1-line invocation site, blocked on dirty-state pattern).

Nexo-rs