# DECISIONS.md

> Append-only architectural decision log. Newest entries at the top.
> Entry format:
>
> ```
> ## YYYY-MM-DD — <short title>
> **Context:** why this came up
> **Decision:** what we chose
> **Rejected:** what we didn't choose and why
> **Consequences:** what this means going forward
> ```

---

## 2026-04-30 — Add `applied_pending` non-terminal status to suggested fixes

**Context:** The verifying banner forces a synchronous verdict — worked / didn't / partial — but a lot of real MSP fixes are async. Engineer ran the script but is waiting on the client to power-cycle, AD replication, an O365 license sync. With only the existing outcomes, the engineer either leaves the banner stale (eroding the verifying signal) or guesses wrong (corrupting outcome data). User flagged the gap directly. Today's `NudgeBanner` "Still checking" button just silences the nudge — it doesn't tell the system anything.

**Decision:** Add a fourth, non-terminal outcome `applied_pending`, parallel to `applied_partial`. Required `pending_reason` Text column stores the "what are you waiting on?" reason. Outcome endpoint allows pending → {success, failed, partial, dismissed} transitions; pending stamps `applied_at` but NOT `verified_at` (it's parked, not verified). Resolution-note generator frames the fix as provisional (no closure language); escalation-package generator surfaces pending verification as the leading hypothesis with a reference to what's being waited on. Frontend exposes the state via a new `PendingBanner` component (info-tone, mirrors `PartialBanner`) plus a "Waiting to verify…" overflow option in the verifying banner. `NudgeBanner` "Still checking" now records pending with a reason instead of just silencing.

**Rejected:**

- **Reuse `applied_partial`.** Semantically wrong — partial means "I did some of it." Pending means "I did all of it, just can't tell if it worked." Generators write different prose for each, and conflating them would lose the distinction in the customer-facing resolution note and the next-engineer escalation handoff.
- **Add a `pending_reason` column without a new status.** The status field is what the dashboard, banner, and generators all branch on. Hiding pending state in a separate column would proliferate `IF pending_reason IS NOT NULL` checks across every consumer.
- **Cross-session "Follow-ups" dashboard rollup in v1.** Per-session `PendingBanner` is the chat-anchored reminder. Add the dashboard surface only if engineers report losing track across multiple pending sessions in pilot use.
- **Optional follow-up timer ("remind me in 30m").** Out of scope; nice-to-have but not the wedge.

**Consequences:**

- Engineers can park a fix honestly without losing the verifying signal. The state survives across sessions because it's persisted server-side.
- `pending_reason` is preserved as audit trail when the engineer advances pending → success/failed/dismissed; it is not auto-cleared. Intentional — it tells the next reader "we waited for X, then it worked."
- New consumers of `FixStatus` must handle the `applied_pending` case. Currently three: the banner derivation in `AssistantChatPage`, the resolution-note generator, and the escalation-package generator. All three updated in this change.
- Migration `c0f3a4b7e91d` is reversible — downgrade rewrites pending rows back to `applied_partial` and copies `pending_reason` into `partial_notes` if the partial slot was empty, then drops the column.

---

## 2026-04-30 — Allow `escalated_to_id` to send chat messages in claimed sessions

**Context:** During browser QA, clicking "Get AI analysis" on the magic-moment screen returned `POST /ai-sessions/{id}/chat → 400`. The senior tech who claimed the session is stored as `escalated_to_id` on `AISession`, not `user_id` (which remains the junior who created the session). `unified_chat_service.send_chat_message` queried `WHERE ai_sessions.user_id = :user_id`, so the senior's ID never matched and the endpoint rejected the request.

**Decision:** Extend the ownership check in `send_chat_message` to `OR ai_sessions.escalated_to_id = :user_id` using SQLAlchemy `or_()`. This is the minimal, correct fix: the session model already has a semantically valid "also owns" field for the claiming senior; extending the WHERE clause makes that ownership real.

**Rejected:**

- **Transfer `user_id` to the senior on claim.** Breaks the audit trail — `user_id` is the originating engineer throughout the session lifecycle. Any query scoped to "sessions this engineer worked on" would silently lose the junior's history.
- **A separate `can_send_message` service method.** Adds indirection with no benefit for v1. One `or_()` line in the existing query is sufficient.
- **Checking a role/permission flag instead.** Role gating (engineer/admin) already happens at the claim endpoint. The chat-send check is about session ownership, not role. Mixing the two concerns would be confusing.

**Consequences:**
- Seniors can send AI briefings and continue chat work in sessions they have claimed. Core escalation pickup flow unblocked.
- Any future caller of `send_chat_message` should be aware that "user_id or escalated_to_id" is the ownership rule. The service-level check is the single enforcement point.
- `user_id` remains the originating engineer for all audit, history, and analytics queries. No data migration needed.

---

## 2026-04-29 — Consolidate the three per-escalation AI calls into one structured generation

**Context:** A single user-initiated escalation currently triggers three separate Sonnet calls, all summarizing the same source material (session state, steps taken, "what we know") from slightly different angles:

1. `_build_escalation_package_enhanced` — runs in the background `enrich_escalation_async` task, builds a rich JSON payload that's saved to `ai_session.escalation_package`.
2. `_generate_ai_assessment` — also background, returns the magic-moment screen fields (`likely_cause`, `suggested_steps[]`, `confidence`).
3. `generate_status_update` — engineer-triggered when they click "Ticket Notes" / "Client Update" / "Email Draft" in the conclude modal, generates audience-specific PSA prose.

The user surfaced the smell: the engineer is *typically* generating a status update during the escalate flow, so the AI assessment work is being done twice with overlapping context and the engineer's PSA prose is being thrown away. Live test on 2026-04-29 also showed that bumping the assessment timeout 15s → 45s did NOT fix the empty-placeholder bug — meaning the architectural smell is also a demo blocker.

**Decision:** ONE structured AI call per escalation that produces a single payload covering both the magic-moment screen's diagnostic fields AND the PSA-ready prose. Persist to `SessionHandoff`. The conclude modal's "Ticket Notes" button reads from the saved prose instead of calling the model. "Client Update" and "Email Draft" buttons trigger a cheap Haiku transformation over the saved prose (tone shift only, not a re-summarization).

Proposed payload shape (final form decided during implementation):

```json
{
  "summary_prose": "<PSA-flavored ticket-notes paragraph>",
  "what_we_know": ["<one-liner>"],
  "likely_cause": "<one sentence>",
  "suggested_steps": ["<short step>"],
  "confidence": "low | medium | high",
  "audience_variants": {"client_update": null, "email_draft": null}
}
```

`audience_variants` filled lazily on first user request, cached.

**Rejected:**

- **Just bumping the timeout further.** Already tried 5s → 15s → 45s. The architectural redundancy is the real cost — even if Sonnet completed reliably, three calls per escalation is wasteful and creates three places where state can diverge.
- **Reusing the engineer's status update content as the AI assessment.** User's first instinct, but: status updates aren't always generated (engineer has to click), they're audience-specific (so you'd pick which one to copy), and they're prose without the structured fields the magic-moment screen needs. The right consolidation is the OTHER direction — generate ONE structured payload that the status-update buttons consume.
- **Switching the assessment to Haiku for speed.** Faster but solves only the latency symptom, not the redundancy. Doesn't help the conclude modal's status-update buttons.

**Consequences:**

- Magic-moment screen populates in ~5s instead of 25s+ (work happens in the foreground escalate path, not in a background task that races with the senior's pickup).
- Token spend per escalation drops by ~60% — one Sonnet call replaces two; the third (audience variants) becomes Haiku.
- Engineer's "Ticket Notes" button is instant — no model round-trip.
- Schema enforcement matters. The current `_generate_ai_assessment` returns freeform prose that the frontend stuffs into `assessment_text` because the structured fields aren't reliably parseable. The new call must use Anthropic's structured output / tool-use to enforce the schema.
- Migration concern: `ai_session.escalation_package` JSON column has live data on existing sessions. Keep it READABLE for backward compatibility; just stop *writing* the enhanced payload from `enrich_escalation_async`. If downstream queue summaries depend on it, dual-write the basic snapshot.
- Test fixtures (`test_handoff_manager.py`, `test_session_handoffs_api.py`) currently stub `_generate_ai_assessment` via `AsyncMock`. Updating the stubs is part of the rename.
- The frontend SSE assessment-ready subscription (added in `0f00ee5`) stays as-is — it just listens for the new event payload.

---

## 2026-04-28 — Tag the task-lane state with an owner chatId

**Context:** A recurring bug — every time the user returned to test escalation work, creating a new session would flash the previous session's task-lane data (questions, actions, "Tasks" pill counts) before the new session's AI response landed. The first attempt to fix it (`8914391`) added initializer-time guards (`incomingPrefill || isPickup`) that skipped the sessionStorage restore on mount. That covered exactly two entry paths and missed every other case: in-place URL navigation, mid-flight pickup, HMR re-runs, and the gap between `setActiveChatId(B)` and the AI response that finally populates B's questions/actions. The persistence effect made it worse by writing `{chatId: activeChatId, questions: activeQuestions}` — at any moment where activeChatId had flipped before the questions were updated, sessionStorage was stamped with `{chatId: B, questions: [A's data]}` and a subsequent restore would happily render A's data for B.

The root cause was that `activeQuestions` / `activeActions` / `showTaskLane` were three independent state slices implicitly assumed to be in sync with `activeChatId`. The synchronization was by convention, not by structure. Every code path that mutated them had to remember to call `resetSessionDerivedState` first; missing one created stale UI.

**Decision:** Add a `taskLaneOwnerChatId` state that records *which chatId the in-memory questions/actions belong to*, set at every site that populates them (sendPrefill, selectChat, handleSend, handleTaskSubmit, handleResumeNew, refreshFacts, handleApplyFix), cleared in `resetSessionDerivedState`. The persistence effect writes ownerChatId as the chatId tag. Render is gated on `taskLaneOwnerChatId === activeChatId` and ANDed into all three render conditions (toolbar Tasks button, narrow-viewport floating drawer, main side panel). The mount-time `skipTaskLaneRestore` guard stays as belt-and-braces for the prefill/pickup entry-flash window, which the owner-gate alone doesn't cover.

**Rejected:**
- **More entry-path guards.** That's whack-a-mole — the next path nobody anticipated will reproduce the bug. The owner-gate makes the bug structurally impossible regardless of which path triggers it.
- **Combining the four state slices into a single tagged object.** Cleaner long-term but a bigger refactor with more touch points. The owner-tracking approach gets the structural guarantee with a minimal diff and keeps the existing setState patterns.
- **Inlining the comparison at every render site.** Works but proliferates the comparison; one named derived value (`taskLaneIsForActiveChat`) reads better and groups the gate with the persistence-effect / state declarations as a named concept.

**Consequences:**
- Stale task-lane data is structurally unable to display. The lane is hidden during any window where `ownerChatId !== activeChatId`, no matter what mutation path got you there.
- Adding new sites that populate `activeQuestions` / `activeActions` requires also setting `taskLaneOwnerChatId`. The pattern is documented in the commit message and visible in every existing populate site as a paired call.
- The mount-time `skipTaskLaneRestore` guard is now redundant in steady-state but kept for the few-hundred-ms flash window between component mount and the first sendPrefill / selectChat effect. Deleting it would re-introduce a (smaller) flash without strong reason.
- Future task-lane state slices (e.g. `facts`, `activeFix`) follow the same pattern: gate their visibility on the owner check via the existing render conditions. Tagging more slices with their own `*OwnerChatId` is a future refactor if the slices diverge.

---

## 2026-04-24 — Adopt dual-agent handoff system (`.ai/` + `CLAUDE.md` + `AGENTS.md`)

**Context:** Claude Code hits session and weekly usage limits. Work stalls when the primary agent is locked out. Needed a structured way for OpenAI Codex to resume where Claude left off without losing architectural truth or drifting across sessions.

**Decision:** Split the old CLAUDE.md into `.ai/PROJECT_CONTEXT.md` (stable repo truth), agent-specific root files (`CLAUDE.md`, `AGENTS.md`) with a shared protocol block, and a small handoff toolkit (`CURRENT_TASK.md`, `HANDOFF.md`, `TODO.md`, `DECISIONS.md`, `SESSION_LOG.md`, `README.md`). Previous CLAUDE.md snapshotted in commit `e110fed` before the migration.

**Rejected:**
- Single symlinked CLAUDE.md/AGENTS.md — diverges silently, hides agent-specific tooling differences.
- Putting GitNexus/gstack content in AGENTS.md — Codex doesn't have those tools; would mislead the resume agent.
- Keeping the old CLAUDE.md as-is and adding AGENTS.md alongside it — duplicated truth, drift guaranteed.

**Consequences:**
- First read for either agent: `.ai/PROJECT_CONTEXT.md` + `.ai/CURRENT_TASK.md` + `.ai/HANDOFF.md`.
- Architectural changes in the repo require updating PROJECT_CONTEXT.md, not the root agent files.
- Git trailers differ per agent (`Claude Opus 4.7` vs `Codex`) — preserved in each root file.
- Legacy `SESSION-HANDOFF.md` deleted in the same commit; superseded by `.ai/HANDOFF.md`.
