feat: unified sessions — merge assistant chat into ai_sessions table

Add session_type ('guided'|'chat') and title columns to ai_sessions,
enabling both FlowPilot guided sessions and assistant chat sessions to
live in a single table. This is the foundation for a unified session
history and consistent UX across both interaction modes.

Backend:
- Migration 066: session_type + title columns
- unified_chat_service: chat sessions on ai_sessions with same AI/RAG
- POST /ai-sessions supports session_type='chat' creation
- POST /ai-sessions/{id}/chat for chat messages
- DELETE /ai-sessions/{id} for session deletion
- session_type filter on GET /ai-sessions

Frontend:
- AssistantChatPage rewired to aiSessionsApi (no more assistantChatApi)
- /assistant/:sessionId route for deep-linking
- Session history: type filter pills (All/Guided/Chat), type icons
- Dashboard: both types shown with correct routing and icons
- Fixed glass-border → border-default in dashboard components

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/alembic/versions/066_add_session_type_and_title_to_ai_sessions.py

@@ -0,0 +1,42 @@
+"""Add session_type and title columns to ai_sessions for unified sessions.
+
+Revision ID: 066
+Revises: 065
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+revision = "066"
+down_revision = "065"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "ai_sessions",
+        sa.Column(
+            "session_type",
+            sa.String(10),
+            nullable=False,
+            server_default="guided",
+            comment="Session type: guided (FlowPilot) or chat (assistant)",
+        ),
+    )
+    op.add_column(
+        "ai_sessions",
+        sa.Column(
+            "title",
+            sa.String(255),
+            nullable=True,
+            comment="Display title for chat sessions; guided sessions use problem_summary",
+        ),
+    )
+    op.create_index("ix_ai_sessions_session_type", "ai_sessions", ["session_type"])
+
+
+def downgrade() -> None:
+    op.drop_index("ix_ai_sessions_session_type", table_name="ai_sessions")
+    op.drop_column("ai_sessions", "title")
+    op.drop_column("ai_sessions", "session_type")

backend/app/api/endpoints/ai_sessions.py

@@ -45,8 +45,12 @@ from app.schemas.ai_session import (
     AISessionStepResponse,
     AISessionSearchResult,
     StepOptionSchema,
+    ChatSessionCreateResponse,
+    ChatMessageRequest,
+    ChatMessageResponse,
 )
 from app.services import flowpilot_engine
+from app.services import unified_chat_service
 from app.services.psa_documentation_service import retry_failed_push
 
 logger = logging.getLogger(__name__)
@@ -89,6 +93,8 @@ def _build_session_detail(session: AISession) -> AISessionDetail:
 
     return AISessionDetail(
         id=session.id,
+        session_type=getattr(session, 'session_type', 'guided'),
+        title=getattr(session, 'title', None),
         status=session.status,
         intake_type=session.intake_type,
         intake_content=session.intake_content or {},
@@ -109,6 +115,7 @@ def _build_session_detail(session: AISession) -> AISessionDetail:
         created_at=session.created_at,
         resolved_at=session.resolved_at,
         steps=step_responses,
+        conversation_messages=session.conversation_messages or [],
     )
 
 
@@ -176,7 +183,7 @@ async def _record_usage(
 
 # ── Create session ──
 
-@router.post("", response_model=AISessionCreateResponse, status_code=201)
+@router.post("", status_code=201)
 @limiter.limit("5/minute")
 async def create_session(
     request: Request,
@@ -185,10 +192,35 @@ async def create_session(
     db: Annotated[AsyncSession, Depends(get_db)],
     _: None = Depends(require_engineer_or_admin),
 ):
-    """Start a new FlowPilot troubleshooting session."""
+    """Start a new FlowPilot or chat session."""
     _require_ai_enabled()
     await _check_quota(current_user, db)
 
+    # Chat sessions use a different creation path
+    if data.session_type == "chat":
+        try:
+            session = await unified_chat_service.create_chat_session(
+                user_id=current_user.id,
+                account_id=current_user.account_id,
+                team_id=current_user.team_id,
+                intake_content=data.intake_content,
+                db=db,
+            )
+        except Exception as e:
+            logger.exception("Chat session creation failed: %s", e)
+            raise HTTPException(
+                status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
+                detail="Failed to create chat session",
+            )
+
+        await db.commit()
+
+        return ChatSessionCreateResponse(
+            session_id=session.id,
+            title=session.title or "New Chat",
+            status=session.status,
+        )
+
     try:
         result = await flowpilot_engine.start_session(
             request=data,
@@ -229,6 +261,70 @@ async def create_session(
     return result
 
 
+# ── Chat message ──
+
+@router.post("/{session_id}/chat", response_model=ChatMessageResponse)
+@limiter.limit("10/minute")
+async def send_chat_message(
+    request: Request,
+    session_id: UUID,
+    data: ChatMessageRequest,
+    current_user: Annotated[User, Depends(get_current_active_user)],
+    db: Annotated[AsyncSession, Depends(get_db)],
+    _: None = Depends(require_engineer_or_admin),
+):
+    """Send a message in a chat session and get AI response."""
+    _require_ai_enabled()
+    await _check_quota(current_user, db)
+
+    user_id = current_user.id
+    account_id = current_user.account_id
+
+    try:
+        ai_content, suggested_flows, session = await unified_chat_service.send_chat_message(
+            session_id=session_id,
+            user_id=user_id,
+            account_id=account_id,
+            message=data.message,
+            db=db,
+        )
+    except ValueError as e:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e))
+    except Exception as e:
+        logger.exception("Chat message failed: %s", e)
+        await db.rollback()
+        try:
+            await _record_usage(
+                current_user, db,
+                generation_type="chat_message",
+                input_tokens=0, output_tokens=0,
+                succeeded=False,
+                session_id=session_id,
+                error_code=type(e).__name__,
+            )
+            await db.commit()
+        except Exception:
+            logger.warning("Failed to record usage after chat failure", exc_info=True)
+        raise HTTPException(
+            status_code=status.HTTP_502_BAD_GATEWAY,
+            detail=f"AI provider error ({type(e).__name__}). Please try again.",
+        )
+
+    await _record_usage(
+        current_user, db,
+        generation_type="chat_message",
+        input_tokens=0, output_tokens=0,
+        succeeded=True,
+        session_id=session_id,
+    )
+    await db.commit()
+
+    return ChatMessageResponse(
+        content=ai_content,
+        suggested_flows=suggested_flows,
+    )
+
+
 # ── Respond to step ──
 
 @router.post("/{session_id}/respond", response_model=StepResponseResponse)
@@ -426,6 +522,29 @@ async def abandon_session(
     await db.commit()
 
 
+# ── Delete ──
+
+@router.delete("/{session_id}", status_code=204)
+async def delete_session(
+    session_id: UUID,
+    current_user: Annotated[User, Depends(get_current_active_user)],
+    db: Annotated[AsyncSession, Depends(get_db)],
+):
+    """Delete a session (owner only)."""
+    result = await db.execute(
+        select(AISession).where(
+            AISession.id == session_id,
+            AISession.user_id == current_user.id,
+        )
+    )
+    session = result.scalar_one_or_none()
+    if not session:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Session not found")
+
+    await db.delete(session)
+    await db.commit()
+
+
 # ── Escalation Queue ──
 
 @router.get("/escalation-queue", response_model=list[AISessionSummary])
@@ -638,6 +757,7 @@ async def list_sessions(
     matched_flow_id: Optional[UUID] = Query(None),
     confidence_tier: Optional[str] = Query(None, pattern="^(guided|exploring|discovery)$"),
     ticket_id: Optional[str] = Query(None),
+    session_type: Optional[str] = Query(None, pattern="^(guided|chat)$"),
     date_from: Optional[datetime] = Query(None),
     date_to: Optional[datetime] = Query(None),
     q: Optional[str] = Query(None, min_length=2, max_length=200),
@@ -657,6 +777,8 @@ async def list_sessions(
         .limit(limit)
     )
 
+    if session_type:
+        query = query.where(AISession.session_type == session_type)
     if session_status:
         query = query.where(AISession.status == session_status)
     if problem_domain:

backend/app/models/ai_session.py

@@ -66,6 +66,16 @@ class AISession(Base):
         index=True,
     )
 
+    # ── Session type ──
+    session_type: Mapped[str] = mapped_column(
+        String(10), nullable=False, default="guided", index=True,
+        comment="Session type: guided (FlowPilot) or chat (assistant)",
+    )
+    title: Mapped[Optional[str]] = mapped_column(
+        String(255), nullable=True,
+        comment="Display title for chat sessions; guided sessions use problem_summary",
+    )
+
     # ── Intake ──
     intake_type: Mapped[str] = mapped_column(
         String(20), nullable=False, default="free_text"

backend/app/schemas/ai_session.py

@@ -11,7 +11,12 @@ from pydantic import BaseModel, Field
 # ── Intake ──
 
 class AISessionCreateRequest(BaseModel):
-    """Start a new FlowPilot session."""
+    """Start a new FlowPilot or chat session."""
+    session_type: str = Field(
+        "guided",
+        pattern="^(guided|chat)$",
+        description="Session type: guided (FlowPilot) or chat (assistant)",
+    )
     intake_type: str = Field(
         "free_text",
         pattern="^(free_text|psa_ticket|screenshot|log_paste|combined)$",
@@ -192,6 +197,8 @@ class LinkTicketRequest(BaseModel):
 class AISessionSummary(BaseModel):
     """Compact session for list views."""
     id: UUID
+    session_type: str = "guided"
+    title: str | None = None
     status: str
     intake_type: str
     problem_summary: str | None = None
@@ -208,7 +215,7 @@ class AISessionSummary(BaseModel):
 
 
 class AISessionDetail(AISessionSummary):
-    """Full session detail with steps."""
+    """Full session detail with steps (guided) or messages (chat)."""
     intake_content: dict[str, Any]
     matched_flow_id: UUID | None = None
     match_score: float | None = None
@@ -220,10 +227,32 @@ class AISessionDetail(AISessionSummary):
     psa_connection_id: UUID | None = None
     ticket_data: dict[str, Any] | None = None
     steps: list[AISessionStepResponse] = []
+    conversation_messages: list[dict[str, Any]] = []  # Chat sessions store messages here
 
     model_config = {"from_attributes": True}
 
 
+# ── Chat session ──
+
+class ChatSessionCreateResponse(BaseModel):
+    """Response after creating a chat session on ai_sessions."""
+    session_id: UUID
+    session_type: str = "chat"
+    title: str
+    status: str = "active"
+
+
+class ChatMessageRequest(BaseModel):
+    """Send a message in a chat session."""
+    message: str = Field(..., min_length=1, max_length=8000)
+
+
+class ChatMessageResponse(BaseModel):
+    """AI response to a chat message."""
+    content: str
+    suggested_flows: list[dict[str, Any]] = []
+
+
 class AISessionSearchResult(BaseModel):
     """Lightweight session result for Command Palette / autocomplete."""
     id: UUID

backend/app/services/unified_chat_service.py

@@ -0,0 +1,125 @@
+"""Unified chat service — chat sessions on ai_sessions table.
+
+Replaces assistant_chat_service for new chat sessions. Messages are stored
+in ai_sessions.conversation_messages JSONB. Reuses the same AI calling
+infrastructure and system prompt from assistant_chat_service.
+"""
+import logging
+from typing import Any
+from uuid import UUID
+
+from sqlalchemy import select
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from app.models.ai_session import AISession
+from app.services.assistant_chat_service import (
+    ASSISTANT_SYSTEM_PROMPT,
+    _call_ai,
+    _auto_title,
+)
+from app.services.rag_service import search as rag_search, build_rag_context, extract_suggested_flows
+
+logger = logging.getLogger(__name__)
+
+
+async def create_chat_session(
+    user_id: UUID,
+    account_id: UUID,
+    team_id: UUID | None,
+    intake_content: dict[str, Any],
+    db: AsyncSession,
+) -> AISession:
+    """Create a new chat session on ai_sessions."""
+    first_message = intake_content.get("text", "")
+    title = _auto_title(first_message) if first_message else "New Chat"
+
+    session = AISession(
+        user_id=user_id,
+        account_id=account_id,
+        team_id=team_id,
+        session_type="chat",
+        title=title,
+        intake_type="free_text",
+        intake_content=intake_content,
+        status="active",
+        confidence_tier="discovery",
+        confidence_score=0.0,
+        conversation_messages=[],
+    )
+    db.add(session)
+    await db.flush()
+    return session
+
+
+async def send_chat_message(
+    session_id: UUID,
+    user_id: UUID,
+    account_id: UUID,
+    message: str,
+    db: AsyncSession,
+) -> tuple[str, list[dict[str, Any]], AISession]:
+    """Send a message in a chat session and get AI response.
+
+    Returns (ai_content, suggested_flows, session).
+    """
+    result = await db.execute(
+        select(AISession).where(
+            AISession.id == session_id,
+            AISession.user_id == user_id,
+            AISession.session_type == "chat",
+        )
+    )
+    session = result.scalar_one_or_none()
+    if not session:
+        raise ValueError("Chat session not found")
+
+    if session.status not in ("active", "paused"):
+        raise ValueError(f"Cannot send messages to a {session.status} session")
+
+    # Auto-title from first message if still default
+    if session.step_count == 0 and message.strip():
+        session.title = _auto_title(message)
+
+    # Auto-detect problem domain from first message
+    if not session.problem_summary and message.strip():
+        session.problem_summary = _auto_title(message)
+
+    # RAG search for relevant flows
+    rag_results = await rag_search(
+        query=message,
+        account_id=account_id,
+        db=db,
+        limit=8,
+    )
+    rag_context = build_rag_context(rag_results)
+
+    # Build message history for AI
+    ai_messages: list[dict[str, Any]] = []
+    for msg in (session.conversation_messages or []):
+        if msg.get("role") in ("user", "assistant"):
+            ai_messages.append({"role": msg["role"], "content": msg["content"]})
+
+    # Call AI
+    ai_content, input_tokens, output_tokens = await _call_ai(
+        system_base=ASSISTANT_SYSTEM_PROMPT,
+        rag_context=rag_context,
+        history=ai_messages,
+        new_message=message,
+    )
+
+    # Append messages to conversation_messages
+    msgs = list(session.conversation_messages or [])
+    msgs.append({"role": "user", "content": message})
+    msgs.append({"role": "assistant", "content": ai_content})
+    session.conversation_messages = msgs
+    session.step_count += 2  # message count for display
+    session.total_input_tokens += input_tokens
+    session.total_output_tokens += output_tokens
+
+    # Resume if paused
+    if session.status == "paused":
+        session.status = "active"
+
+    suggested_flows = extract_suggested_flows(rag_results)
+
+    return ai_content, suggested_flows, session

docs/plans/2026-03-23-unified-sessions.md

@@ -0,0 +1,130 @@
+# Unified Sessions — Migration Plan
+
+> **Date:** 2026-03-23
+> **Status:** Implementation ready
+> **Goal:** Merge assistant chat into the ai_sessions system so both guided (FlowPilot) and free-form (chat) sessions share the same data model, history, and action system.
+
+## Problem
+
+Three separate conversation systems exist:
+1. `assistant_chats` — free-form chat, JSONB messages inline, no steps
+2. `ai_sessions` + `ai_session_steps` — guided FlowPilot, separate steps table
+3. `ai_chat_sessions` — flow builder (unrelated, leave alone)
+
+This causes:
+- No unified session history
+- Assistant chats missing Resolve/Escalate/Update actions
+- Dashboard can't show assistant chats in active/recent
+- Two separate API surfaces to maintain
+
+## Solution
+
+Add `session_type` to `ai_sessions`. Chat sessions use `conversation_messages` JSONB for message history (already exists). Both types share the same status, PSA, escalation, and documentation features.
+
+## Data Model Changes
+
+### Migration: Add `session_type` to `ai_sessions`
+
+```sql
+ALTER TABLE ai_sessions ADD COLUMN session_type VARCHAR(10) NOT NULL DEFAULT 'guided';
+-- Values: 'guided' (FlowPilot), 'chat' (assistant)
+```
+
+### How chat sessions use ai_sessions
+
+| ai_sessions column | Chat usage |
+|---|---|
+| `session_type` | `'chat'` |
+| `intake_type` | `'free_text'` |
+| `intake_content` | `{text: "first message"}` |
+| `conversation_messages` | Full chat history as JSONB array `[{role, content}]` |
+| `status` | Same: active/resolved/escalated/paused/abandoned |
+| `problem_summary` | AI-generated from first few messages |
+| `problem_domain` | AI-detected domain |
+| `step_count` | Message count (for display) |
+| `resolution_summary` | Set on resolve |
+| `escalation_reason` | Set on escalate |
+| All PSA fields | Same — can link tickets, push notes |
+| All timestamps | Same |
+
+### What chat sessions DON'T use
+
+- `ai_session_steps` table — no steps, messages are in `conversation_messages`
+- `matched_flow_id` / `match_score` — no flow matching
+- `confidence_tier` / `confidence_score` — no structured confidence
+- `system_prompt_snapshot` — could store chat system prompt
+
+### New field on ai_sessions
+
+- `title` (String 255, nullable) — chat sessions need a title for the sidebar. Guided sessions can use `problem_summary`.
+
+## Implementation Phases
+
+### Phase 1: Backend — Model & Migration
+- [ ] Alembic migration: add `session_type` VARCHAR(10) default 'guided', add `title` VARCHAR(255) nullable
+- [ ] Update AISession model with new columns
+- [ ] Update schemas: add `session_type` and `title` to response schemas
+- [ ] Add session_type filter to GET /ai-sessions endpoint
+
+### Phase 2: Backend — Chat API on ai_sessions
+- [ ] Create new endpoints or extend existing:
+  - `POST /ai-sessions` with `session_type: 'chat'` — creates a chat session
+  - `POST /ai-sessions/{id}/chat` — send message, get AI response (appends to conversation_messages)
+  - Reuse existing: resolve, escalate, pause, abandon, status-update
+- [ ] Chat AI service: takes conversation_messages, calls Anthropic, appends response
+- [ ] Auto-generate title from first message (like current assistant chat does)
+- [ ] Auto-detect problem_domain from conversation
+
+### Phase 3: Frontend — Unified Session History
+- [ ] Update SessionHistoryPage to show both types
+- [ ] Add type icon: compass/route for guided, message-circle for chat
+- [ ] Session detail page routes correctly based on type
+- [ ] Add session_type filter option
+
+### Phase 4: Frontend — Assistant Chat on ai_sessions
+- [ ] Update AssistantChatPage to use ai_sessions API instead of assistant_chats
+- [ ] Chat sidebar queries ai_sessions with `session_type=chat`
+- [ ] Messages read from / write to `conversation_messages`
+- [ ] Add header actions: Resolve / Escalate / Share Update / Pause / Close
+- [ ] Status update modal works the same as FlowPilot
+
+### Phase 5: Frontend — Dashboard Integration
+- [ ] ActiveFlowPilotSessions includes chat sessions (both types)
+- [ ] RecentFlowPilotSessions includes resolved chats
+- [ ] Type icon on each card so users see the difference at a glance
+
+### Phase 6: Cleanup
+- [ ] Migrate existing assistant_chat data to ai_sessions (optional — could just start fresh for pilot)
+- [ ] Deprecate /assistant/* API endpoints
+- [ ] Remove assistant_chats model (post-pilot)
+
+## Visual Differentiators
+
+| Type | Icon | Badge color | Label |
+|------|------|------------|-------|
+| Guided (FlowPilot) | `<Route size={14} />` | cyan | "Guided" |
+| Chat (Assistant) | `<MessageCircle size={14} />` | purple/violet | "Chat" |
+
+## API Surface (after migration)
+
+All under `/ai-sessions`:
+
+| Endpoint | Both types? | Notes |
+|----------|------------|-------|
+| `POST /ai-sessions` | Yes | `session_type` field determines behavior |
+| `GET /ai-sessions` | Yes | Filter by `session_type` optional |
+| `GET /ai-sessions/{id}` | Yes | Returns full session with messages or steps |
+| `POST /ai-sessions/{id}/chat` | Chat only | Send/receive messages |
+| `POST /ai-sessions/{id}/respond` | Guided only | Step response |
+| `POST /ai-sessions/{id}/resolve` | Both | Same resolve flow |
+| `POST /ai-sessions/{id}/escalate` | Both | Same escalation |
+| `POST /ai-sessions/{id}/pause` | Both | Same pause |
+| `POST /ai-sessions/{id}/abandon` | Both | Same abandon |
+| `POST /ai-sessions/{id}/status-update` | Both | Same status updates |
+
+## Risk Assessment
+
+- **Low risk:** Adding columns to ai_sessions is additive, no existing data changes
+- **Medium risk:** Frontend routing — need to route to correct page based on session_type
+- **Data migration:** Can skip for pilot — start with fresh chat sessions on new system. Old assistant_chats remain accessible via old API until removed.
+- **Rollback:** session_type column is additive, old assistant_chat endpoints can stay as fallback

frontend/src/api/aiSessions.ts

@@ -15,6 +15,9 @@ import type {
   PickupSessionRequest,
   StatusUpdateRequest,
   StatusUpdateResponse,
+  ChatSessionCreateResponse,
+  ChatMessageRequest,
+  ChatMessageResponse,
 } from '@/types/ai-session'
 
 export const aiSessionsApi = {
@@ -23,6 +26,22 @@ export const aiSessionsApi = {
     return response.data
   },
 
+  async createChatSession(data: AISessionCreateRequest): Promise<ChatSessionCreateResponse> {
+    const response = await apiClient.post<ChatSessionCreateResponse>('/ai-sessions', {
+      ...data,
+      session_type: 'chat',
+    })
+    return response.data
+  },
+
+  async sendChatMessage(sessionId: string, data: ChatMessageRequest): Promise<ChatMessageResponse> {
+    const response = await apiClient.post<ChatMessageResponse>(
+      `/ai-sessions/${sessionId}/chat`,
+      data
+    )
+    return response.data
+  },
+
   async respondToStep(sessionId: string, data: StepResponseRequest): Promise<StepResponseResponse> {
     const response = await apiClient.post<StepResponseResponse>(
       `/ai-sessions/${sessionId}/respond`,
@@ -49,6 +68,7 @@ export const aiSessionsApi = {
 
   async listSessions(params?: {
     status?: string
+    session_type?: string
     skip?: number
     limit?: number
     problem_domain?: string
@@ -104,6 +124,10 @@ export const aiSessionsApi = {
     })
   },
 
+  async deleteSession(sessionId: string): Promise<void> {
+    await apiClient.delete(`/ai-sessions/${sessionId}`)
+  },
+
   async pickupSession(sessionId: string, data: PickupSessionRequest): Promise<StepResponseResponse> {
     const response = await apiClient.post<StepResponseResponse>(
       `/ai-sessions/${sessionId}/pickup`,

frontend/src/components/dashboard/ActiveFlowPilotSessions.tsx

@@ -1,6 +1,6 @@
 import { useState, useEffect } from 'react'
 import { Link, useNavigate } from 'react-router-dom'
-import { Sparkles, Clock, ArrowRight } from 'lucide-react'
+import { Clock, ArrowRight, Route, MessageCircle } from 'lucide-react'
 import { aiSessionsApi } from '@/api/aiSessions'
 import type { AISessionSummary } from '@/types/ai-session'
 import { cn } from '@/lib/utils'
@@ -30,7 +30,7 @@ export function ActiveFlowPilotSessions() {
   if (loading) {
     return (
       <div className="card-flat">
-        <div className="px-5 py-3" style={{ borderBottom: '1px solid var(--glass-border)' }}>
+        <div className="px-5 py-3" style={{ borderBottom: '1px solid var(--color-border-default)' }}>
           <h3 className="font-heading text-sm font-bold text-foreground">Active Sessions</h3>
         </div>
         <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-3 p-4">
@@ -46,7 +46,7 @@ export function ActiveFlowPilotSessions() {
     <div className="card-flat">
       <div
         className="flex items-center justify-between px-5 py-3"
-        style={{ borderBottom: '1px solid var(--glass-border)' }}
+        style={{ borderBottom: '1px solid var(--color-border-default)' }}
       >
         <div className="flex items-center gap-2">
           <h3 className="font-heading text-sm font-bold text-foreground">Active Sessions</h3>
@@ -74,11 +74,15 @@ export function ActiveFlowPilotSessions() {
           {sessions.map((session) => (
             <button
               key={session.id}
-              onClick={() => navigate(`/pilot/${session.id}`)}
+              onClick={() => navigate(session.session_type === 'chat' ? `/assistant/${session.id}` : `/pilot/${session.id}`)}
               className="card-interactive p-4 text-left"
             >
               <div className="flex items-start justify-between gap-2 mb-2">
-                <Sparkles size={14} className="shrink-0 text-primary mt-0.5" />
+                {session.session_type === 'chat' ? (
+                  <MessageCircle size={14} className="shrink-0 text-violet-400 mt-0.5" />
+                ) : (
+                  <Route size={14} className="shrink-0 text-primary mt-0.5" />
+                )}
                 <span
                   className={cn(
                     'font-sans text-xs text-[0.5625rem] uppercase px-1.5 py-0.5 rounded',
@@ -92,7 +96,9 @@ export function ActiveFlowPilotSessions() {
                 </span>
               </div>
               <p className="text-sm font-medium text-foreground truncate">
-                {session.problem_summary || 'Session in progress'}
+                {session.session_type === 'chat'
+                  ? (session.title || session.problem_summary || 'Chat in progress')
+                  : (session.problem_summary || 'Session in progress')}
               </p>
               <div className="mt-2 flex items-center gap-2 text-[0.625rem] text-muted-foreground">
                 <span className="flex items-center gap-1">
@@ -100,7 +106,7 @@ export function ActiveFlowPilotSessions() {
                   {timeAgo(session.created_at)}
                 </span>
                 <span>&middot;</span>
-                <span>{session.step_count} steps</span>
+                <span>{session.step_count} {session.session_type === 'chat' ? 'messages' : 'steps'}</span>
               </div>
             </button>
           ))}

frontend/src/components/dashboard/RecentFlowPilotSessions.tsx

@@ -1,6 +1,6 @@
 import { useState, useEffect } from 'react'
 import { Link, useNavigate } from 'react-router-dom'
-import { CheckCircle, AlertTriangle, XCircle, ArrowRight } from 'lucide-react'
+import { CheckCircle, AlertTriangle, XCircle, ArrowRight, MessageCircle } from 'lucide-react'
 import { aiSessionsApi } from '@/api/aiSessions'
 import type { AISessionSummary } from '@/types/ai-session'
 
@@ -44,7 +44,7 @@ export function RecentFlowPilotSessions() {
     <div className="card-flat">
       <div
         className="flex items-center justify-between px-5 py-3"
-        style={{ borderBottom: '1px solid var(--glass-border)' }}
+        style={{ borderBottom: '1px solid var(--color-border-default)' }}
       >
         <h3 className="font-heading text-sm font-bold text-foreground">Recent Sessions</h3>
         <Link
@@ -61,16 +61,22 @@ export function RecentFlowPilotSessions() {
           return (
             <button
               key={session.id}
-              onClick={() => navigate(`/pilot/${session.id}`)}
+              onClick={() => navigate(session.session_type === 'chat' ? `/assistant/${session.id}` : `/pilot/${session.id}`)}
               className="flex w-full items-center gap-3 px-5 py-3 text-left hover:bg-[rgba(255,255,255,0.02)] transition-colors"
               style={{
-                borderBottom: i < sessions.length - 1 ? '1px solid var(--glass-border)' : undefined,
+                borderBottom: i < sessions.length - 1 ? '1px solid var(--color-border-default)' : undefined,
               }}
             >
-              <StatusIcon size={14} style={{ color: config.color }} className="shrink-0" />
+              {session.session_type === 'chat' ? (
+                <MessageCircle size={14} className="shrink-0 text-violet-400" />
+              ) : (
+                <StatusIcon size={14} style={{ color: config.color }} className="shrink-0" />
+              )}
               <div className="flex-1 min-w-0">
                 <p className="text-sm text-foreground truncate">
-                  {session.problem_summary || 'Session'}
+                  {session.session_type === 'chat'
+                    ? (session.title || session.problem_summary || 'Chat')
+                    : (session.problem_summary || 'Session')}
                 </p>
               </div>
               <span className="shrink-0 font-sans text-xs text-muted-foreground">

frontend/src/components/flowpilot/AISessionListItem.tsx

@@ -1,5 +1,5 @@
 import { Link } from 'react-router-dom'
-import { Clock, CheckCircle2, ArrowUpRight, AlertCircle, Pause } from 'lucide-react'
+import { Clock, CheckCircle2, ArrowUpRight, AlertCircle, Pause, Route, MessageCircle } from 'lucide-react'
 import { cn } from '@/lib/utils'
 import type { AISessionSummary } from '@/types/ai-session'
 
@@ -18,17 +18,31 @@ const STATUS_CONFIG = {
 export function AISessionListItem({ session }: AISessionListItemProps) {
   const config = STATUS_CONFIG[session.status as keyof typeof STATUS_CONFIG] ?? STATUS_CONFIG.active
   const StatusIcon = config.icon
+  const isChat = session.session_type === 'chat'
+  const TypeIcon = isChat ? MessageCircle : Route
+  const linkTo = isChat ? `/assistant/${session.id}` : `/pilot/${session.id}`
+  const displayTitle = isChat
+    ? (session.title || session.problem_summary || 'Untitled chat')
+    : (session.problem_summary || 'Untitled session')
 
   return (
     <Link
-      to={`/pilot/${session.id}`}
+      to={linkTo}
       className="card-interactive block p-4 transition-all"
     >
       <div className="flex items-start justify-between gap-3">
         <div className="flex-1 min-w-0">
-          <p className="text-sm font-medium text-foreground truncate">
-            {session.problem_summary || 'Untitled session'}
-          </p>
+          <div className="flex items-center gap-2">
+            <span className={cn(
+              'flex items-center justify-center w-5 h-5 rounded',
+              isChat ? 'text-violet-400' : 'text-primary'
+            )}>
+              <TypeIcon size={14} />
+            </span>
+            <p className="text-sm font-medium text-foreground truncate">
+              {displayTitle}
+            </p>
+          </div>
           <div className="mt-1.5 flex items-center gap-3 flex-wrap">
             {session.problem_domain && (
               <span className="font-sans text-xs rounded-md bg-accent-dim px-2 py-0.5 text-[0.625rem] uppercase tracking-wider text-primary">
@@ -40,7 +54,7 @@ export function AISessionListItem({ session }: AISessionListItemProps) {
               {config.label}
             </span>
             <span className="text-xs text-muted-foreground">
-              {session.step_count} steps
+              {session.step_count} {isChat ? 'messages' : 'steps'}
             </span>
             <span className="text-xs text-text-muted">
               {new Date(session.created_at).toLocaleDateString(undefined, {

frontend/src/hooks/useFlowPilotSession.ts

@@ -69,6 +69,8 @@ export function useFlowPilotSession(): UseFlowPilotSession {
 
       setSession({
         id: result.session_id,
+        session_type: 'guided',
+        title: null,
         status: result.status,
         intake_type: intake.intake_type,
         intake_content: intake.intake_content,
@@ -89,6 +91,7 @@ export function useFlowPilotSession(): UseFlowPilotSession {
         psa_connection_id: intake.psa_connection_id ?? null,
         ticket_data: null,
         steps: [firstStep],
+        conversation_messages: [],
       })
       setAllSteps([firstStep])
       setCurrentStep(firstStep)

frontend/src/pages/AssistantChatPage.tsx

@@ -1,28 +1,31 @@
 import { useState, useEffect, useRef, useCallback } from 'react'
-import { useLocation, useNavigate } from 'react-router-dom'
+import { useLocation, useNavigate, useParams } from 'react-router-dom'
 import { Sparkles, Send, Loader2, Flag, MessageSquare, Paperclip, Terminal, X, RotateCcw, ImagePlus } from 'lucide-react'
 import { cn } from '@/lib/utils'
 import { uploadsApi } from '@/api/uploads'
 import type { PendingUpload } from '@/types/upload'
 import { PageMeta } from '@/components/common/PageMeta'
-import { assistantChatApi } from '@/api/assistantChat'
+import { aiSessionsApi } from '@/api/aiSessions'
 import { analytics } from '@/lib/analytics'
 import { toast } from '@/lib/toast'
 import { ChatSidebar } from '@/components/assistant/ChatSidebar'
 import { ChatMessage } from '@/components/assistant/ChatMessage'
 import { ConcludeSessionModal } from '@/components/assistant/ConcludeSessionModal'
-import type { ChatListItem, AssistantChatMessage as ChatMessageType, ConclusionOutcome } from '@/types/assistant-chat'
+import type { ChatListItem, ConclusionOutcome } from '@/types/assistant-chat'
 import type { SuggestedFlow } from '@/types/copilot'
 
-interface MessageWithMeta extends ChatMessageType {
+interface MessageWithMeta {
+  role: 'user' | 'assistant'
+  content: string
   suggestedFlows?: SuggestedFlow[]
 }
 
 export default function AssistantChatPage() {
   const location = useLocation()
   const navigate = useNavigate()
+  const { sessionId: urlSessionId } = useParams<{ sessionId?: string }>()
   const [chats, setChats] = useState<ChatListItem[]>([])
-  const [activeChatId, setActiveChatId] = useState<string | null>(null)
+  const [activeChatId, setActiveChatId] = useState<string | null>(urlSessionId || null)
   const [messages, setMessages] = useState<MessageWithMeta[]>([])
   const [input, setInput] = useState('')
   const [loading, setLoading] = useState(false)
@@ -38,39 +41,53 @@ export default function AssistantChatPage() {
   const dragCounterRef = useRef(0)
   const prefillHandledRef = useRef(false)
 
-  // Load chat list
+  // Load chat list from ai_sessions
   useEffect(() => {
     loadChats()
   }, [])
 
-  // Handle prefill from command palette handoff
+  // If URL has a session ID, load it
+  useEffect(() => {
+    if (urlSessionId && urlSessionId !== activeChatId) {
+      selectChat(urlSessionId)
+    }
+  }, [urlSessionId]) // eslint-disable-line react-hooks/exhaustive-deps
+
+  // Handle prefill from command palette / dashboard handoff
   useEffect(() => {
     const prefill = (location.state as { prefill?: string } | null)?.prefill
     if (!prefill || prefillHandledRef.current) return
     prefillHandledRef.current = true
 
-    // Clear the location state so back-navigation doesn't retrigger
     navigate(location.pathname, { replace: true, state: {} })
 
     const sendPrefill = async () => {
       try {
-        const chat = await assistantChatApi.createChat()
-        setChats(prev => [
-          { id: chat.id, title: chat.title, message_count: 0, pinned: false, created_at: chat.created_at, updated_at: chat.updated_at },
-          ...prev,
-        ])
-        setActiveChatId(chat.id)
+        const session = await aiSessionsApi.createChatSession({
+          intake_type: 'free_text',
+          intake_content: { text: prefill },
+        })
+        const chatItem: ChatListItem = {
+          id: session.session_id,
+          title: session.title,
+          message_count: 0,
+          pinned: false,
+          created_at: new Date().toISOString(),
+          updated_at: new Date().toISOString(),
+        }
+        setChats(prev => [chatItem, ...prev])
+        setActiveChatId(session.session_id)
         setMessages([{ role: 'user', content: prefill }])
         setLoading(true)
 
-        const response = await assistantChatApi.sendMessage(chat.id, prefill)
+        const response = await aiSessionsApi.sendChatMessage(session.session_id, { message: prefill })
         setMessages(prev => [
           ...prev,
           { role: 'assistant', content: response.content, suggestedFlows: response.suggested_flows },
         ])
         setChats(prev =>
           prev.map(c =>
-            c.id === chat.id
+            c.id === session.session_id
               ? { ...c, message_count: 2, title: prefill.slice(0, 100), updated_at: new Date().toISOString() }
               : c
           )
@@ -93,8 +110,15 @@ export default function AssistantChatPage() {
 
   const loadChats = async () => {
     try {
-      const list = await assistantChatApi.listChats(1, 100)
-      setChats(list)
+      const sessions = await aiSessionsApi.listSessions({ session_type: 'chat', limit: 100 })
+      setChats(sessions.map(s => ({
+        id: s.id,
+        title: s.title || s.problem_summary || 'New Chat',
+        message_count: s.step_count,
+        pinned: false,
+        created_at: s.created_at,
+        updated_at: s.created_at,
+      })))
     } catch {
       // silently handle
     }
@@ -103,8 +127,13 @@ export default function AssistantChatPage() {
   const selectChat = useCallback(async (chatId: string) => {
     setActiveChatId(chatId)
     try {
-      const chat = await assistantChatApi.getChat(chatId)
-      setMessages(chat.messages.map(m => ({ ...m })))
+      const detail = await aiSessionsApi.getSession(chatId)
+      setMessages(
+        (detail.conversation_messages || []).map(m => ({
+          role: m.role as 'user' | 'assistant',
+          content: m.content,
+        }))
+      )
     } catch {
       setMessages([])
     }
@@ -112,12 +141,20 @@ export default function AssistantChatPage() {
 
   const handleNewChat = async () => {
     try {
-      const chat = await assistantChatApi.createChat()
-      setChats(prev => [
-        { id: chat.id, title: chat.title, message_count: 0, pinned: false, created_at: chat.created_at, updated_at: chat.updated_at },
-        ...prev,
-      ])
-      setActiveChatId(chat.id)
+      const session = await aiSessionsApi.createChatSession({
+        intake_type: 'free_text',
+        intake_content: { text: '' },
+      })
+      const chatItem: ChatListItem = {
+        id: session.session_id,
+        title: session.title,
+        message_count: 0,
+        pinned: false,
+        created_at: new Date().toISOString(),
+        updated_at: new Date().toISOString(),
+      }
+      setChats(prev => [chatItem, ...prev])
+      setActiveChatId(session.session_id)
       setMessages([])
     } catch {
       toast.error('Failed to create chat')
@@ -126,7 +163,7 @@ export default function AssistantChatPage() {
 
   const handleDeleteChat = async (chatId: string) => {
     try {
-      await assistantChatApi.deleteChat(chatId)
+      await aiSessionsApi.deleteSession(chatId)
       setChats(prev => prev.filter(c => c.id !== chatId))
       if (activeChatId === chatId) {
         setActiveChatId(null)
@@ -137,15 +174,9 @@ export default function AssistantChatPage() {
     }
   }
 
-  const handleTogglePin = async (chatId: string, pinned: boolean) => {
-    try {
-      await assistantChatApi.updateChat(chatId, { pinned })
-      setChats(prev =>
-        prev.map(c => c.id === chatId ? { ...c, pinned } : c)
-      )
-    } catch {
-      toast.error('Failed to update chat')
-    }
+  const handleTogglePin = async (_chatId: string, _pinned: boolean) => {
+    // Pin/unpin not yet supported on unified sessions — no-op for now
+    toast.info('Pin feature coming soon')
   }
 
   const handleSend = async () => {
@@ -157,13 +188,12 @@ export default function AssistantChatPage() {
     setLoading(true)
 
     try {
-      const response = await assistantChatApi.sendMessage(activeChatId, userMessage)
+      const response = await aiSessionsApi.sendChatMessage(activeChatId, { message: userMessage })
       analytics.aiFeatureUsed({ feature: 'assistant_chat' })
       setMessages(prev => [
         ...prev,
         { role: 'assistant', content: response.content, suggestedFlows: response.suggested_flows },
       ])
-      // Update chat list title if it was the first message
       setChats(prev =>
         prev.map(c =>
           c.id === activeChatId
@@ -182,44 +212,55 @@ export default function AssistantChatPage() {
     }
   }
 
-  const handleConclude = async (outcome: ConclusionOutcome, notes: string): Promise<string> => {
+  const handleConclude = async (outcome: ConclusionOutcome, _notes: string): Promise<string> => {
     if (!activeChatId) throw new Error('No active chat')
-    const response = await assistantChatApi.concludeChat(activeChatId, { outcome, notes: notes || undefined })
-    // Update chat in sidebar to show concluded status
-    setChats(prev =>
-      prev.map(c =>
-        c.id === activeChatId
-          ? { ...c, concluded_at: response.concluded_at, conclusion_outcome: outcome }
-          : c
-      )
-    )
-    return response.summary
+
+    // Map conclusion outcomes to ai_sessions actions
+    if (outcome === 'resolved') {
+      const result = await aiSessionsApi.resolveSession(activeChatId, {
+        resolution_summary: _notes || 'Resolved via assistant chat',
+      })
+      return result.documentation?.problem_summary || 'Session resolved'
+    } else if (outcome === 'escalated') {
+      const result = await aiSessionsApi.escalateSession(activeChatId, {
+        escalation_reason: _notes || 'Escalated from assistant chat',
+      })
+      return result.documentation?.problem_summary || 'Session escalated'
+    } else {
+      // paused
+      await aiSessionsApi.pauseSession(activeChatId)
+      return 'Session paused'
+    }
   }
 
   const handleResumeNew = async (summary: string) => {
     try {
-      const chat = await assistantChatApi.createChat()
-      setChats(prev => [
-        { id: chat.id, title: chat.title, message_count: 0, pinned: false, created_at: chat.created_at, updated_at: chat.updated_at },
-        ...prev,
-      ])
-      setActiveChatId(chat.id)
-      setMessages([])
-
-      // Send the summary as the first message to prime the new chat
       const resumePrompt = `I'm continuing a previous troubleshooting session. Here's where we left off:\n\n${summary}\n\nPlease review this context and help me continue from where we stopped.`
-      setInput('')
+      const session = await aiSessionsApi.createChatSession({
+        intake_type: 'free_text',
+        intake_content: { text: resumePrompt },
+      })
+      const chatItem: ChatListItem = {
+        id: session.session_id,
+        title: session.title,
+        message_count: 0,
+        pinned: false,
+        created_at: new Date().toISOString(),
+        updated_at: new Date().toISOString(),
+      }
+      setChats(prev => [chatItem, ...prev])
+      setActiveChatId(session.session_id)
       setMessages([{ role: 'user', content: resumePrompt }])
       setLoading(true)
 
-      const response = await assistantChatApi.sendMessage(chat.id, resumePrompt)
+      const response = await aiSessionsApi.sendChatMessage(session.session_id, { message: resumePrompt })
       setMessages(prev => [
         ...prev,
         { role: 'assistant', content: response.content, suggestedFlows: response.suggested_flows },
       ])
       setChats(prev =>
         prev.map(c =>
-          c.id === chat.id
+          c.id === session.session_id
             ? { ...c, message_count: 2, title: resumePrompt.slice(0, 100), updated_at: new Date().toISOString() }
             : c
         )

frontend/src/pages/SessionHistoryPage.tsx

@@ -27,6 +27,7 @@ export function SessionHistoryPage() {
   const aiSearchTimeout = useRef<ReturnType<typeof setTimeout> | undefined>(undefined)
   const [aiFilters, setAiFilters] = useState({
     q: '',
+    session_type: '',
     problem_domain: '',
     confidence_tier: '',
     date_from: '',
@@ -176,6 +177,7 @@ export function SessionHistoryPage() {
         const data = await aiSessionsApi.listSessions({
           limit: 50,
           q: aiFilters.q || undefined,
+          session_type: aiFilters.session_type || undefined,
           problem_domain: aiFilters.problem_domain || undefined,
           confidence_tier: aiFilters.confidence_tier || undefined,
           date_from: aiFilters.date_from || undefined,
@@ -267,7 +269,7 @@ export function SessionHistoryPage() {
     return labels[outcome] ?? outcome
   }
 
-  const hasAiFiltersActive = !!(aiSearchInput || aiFilters.q || aiFilters.problem_domain || aiFilters.confidence_tier || aiFilters.date_from || aiFilters.date_to)
+  const hasAiFiltersActive = !!(aiSearchInput || aiFilters.q || aiFilters.session_type || aiFilters.problem_domain || aiFilters.confidence_tier || aiFilters.date_from || aiFilters.date_to)
   const hasFlowFiltersActive = !!(filters.ticketNumber || filters.clientName || filters.treeName || filters.dateRange?.from)
 
   // Determine section visibility
@@ -314,7 +316,7 @@ export function SessionHistoryPage() {
       {/* FlowPilot Sessions Section */}
       {showAiSection && (
         <>
-          <h2 className="font-sans text-xs text-[0.625rem] uppercase tracking-[0.1em] text-muted-foreground mb-3">FlowPilot Sessions</h2>
+          <h2 className="font-sans text-xs text-[0.625rem] uppercase tracking-[0.1em] text-muted-foreground mb-3">AI Sessions</h2>
 
           {/* AI Session Filter Bar */}
           <div className="card-flat p-3 mb-4">
@@ -331,6 +333,24 @@ export function SessionHistoryPage() {
                 />
               </div>
 
+              {/* Session type pills */}
+              <div className="flex gap-1">
+                {(['', 'guided', 'chat'] as const).map((t) => (
+                  <button
+                    key={t}
+                    onClick={() => setAiFilters((f) => ({ ...f, session_type: t }))}
+                    className={cn(
+                      'rounded-full border px-3 py-1 text-xs font-sans transition-colors',
+                      aiFilters.session_type === t
+                        ? 'bg-accent-dim text-foreground border-primary/30'
+                        : 'bg-card text-muted-foreground border-border hover:text-foreground hover:border-[rgba(255,255,255,0.12)]'
+                    )}
+                  >
+                    {t === '' ? 'All' : t === 'guided' ? 'Guided' : 'Chat'}
+                  </button>
+                ))}
+              </div>
+
               {/* Problem domain dropdown */}
               <select
                 value={aiFilters.problem_domain}
@@ -393,7 +413,7 @@ export function SessionHistoryPage() {
                 <button
                   onClick={() => {
                     setAiSearchInput('')
-                    setAiFilters({ q: '', problem_domain: '', confidence_tier: '', date_from: '', date_to: '' })
+                    setAiFilters({ q: '', session_type: '', problem_domain: '', confidence_tier: '', date_from: '', date_to: '' })
                   }}
                   className="text-xs text-muted-foreground hover:text-foreground transition-colors"
                 >
@@ -415,7 +435,7 @@ export function SessionHistoryPage() {
                 <button
                   onClick={() => {
                     setAiSearchInput('')
-                    setAiFilters({ q: '', problem_domain: '', confidence_tier: '', date_from: '', date_to: '' })
+                    setAiFilters({ q: '', session_type: '', problem_domain: '', confidence_tier: '', date_from: '', date_to: '' })
                   }}
                   className="text-foreground hover:underline text-sm"
                 >

frontend/src/router.tsx

@@ -194,6 +194,7 @@ export const router = sentryCreateBrowserRouter([
       { path: 'script-builder', element: page(ScriptBuilderPage) },
       { path: 'kb-accelerator', element: page(KBAcceleratorPage) },
       { path: 'assistant', element: page(AssistantChatPage) },
+      { path: 'assistant/:sessionId', element: page(AssistantChatPage) },
       { path: 'flow-assist', element: page(FlowAssistPage) },
       { path: 'pilot', element: page(FlowPilotSessionPage) },
       { path: 'pilot/:sessionId', element: page(FlowPilotSessionPage) },

frontend/src/types/ai-session.ts

@@ -1,6 +1,9 @@
 // ── Intake ──
 
+export type SessionType = 'guided' | 'chat'
+
 export interface AISessionCreateRequest {
+  session_type?: SessionType
   intake_type: 'free_text' | 'psa_ticket' | 'screenshot' | 'log_paste' | 'combined'
   intake_content: Record<string, unknown>
   psa_ticket_id?: string
@@ -159,6 +162,8 @@ export interface RateSessionRequest {
 
 export interface AISessionSummary {
   id: string
+  session_type: SessionType
+  title: string | null
   status: string
   intake_type: string
   problem_summary: string | null
@@ -189,6 +194,7 @@ export interface AISessionDetail extends AISessionSummary {
   psa_connection_id: string | null
   ticket_data: Record<string, unknown> | null
   steps: AISessionStepResponse[]
+  conversation_messages: Array<{ role: string; content: string }>
 }
 
 export interface AISessionSearchResult {
@@ -199,6 +205,24 @@ export interface AISessionSearchResult {
   created_at: string
 }
 
+// ── Chat session ──
+
+export interface ChatSessionCreateResponse {
+  session_id: string
+  session_type: 'chat'
+  title: string
+  status: string
+}
+
+export interface ChatMessageRequest {
+  message: string
+}
+
+export interface ChatMessageResponse {
+  content: string
+  suggested_flows: Array<{ tree_id: string; tree_name: string; tree_type: string; relevance_snippet: string }>
+}
+
 export interface SimilarSession {
   id: string
   problem_summary: string | null