feat: Implement session management and search functionality

- Added SDK session, observation, and summary types to types.ts.
- Refactored worker-service to use SessionStore for session management.
- Created SessionSearch class for FTS5 full-text search and structured queries.
- Implemented SessionStore for CRUD operations on SDK sessions, observations, and summaries.
- Added migrations for database schema updates, including new columns and constraints.
- Enhanced search capabilities with filters for projects, types, concepts, and date ranges.

src/services/sqlite/SessionSearch.ts

@@ -0,0 +1,525 @@
+import Database from 'better-sqlite3';
+import { DATA_DIR, DB_PATH, ensureDir } from '../../shared/paths.js';
+import {
+  ObservationSearchResult,
+  SessionSummarySearchResult,
+  SearchOptions,
+  SearchFilters,
+  DateRange,
+  ObservationRow
+} from './types.js';
+
+/**
+ * Search interface for session-based memory
+ * Provides FTS5 full-text search and structured queries for sessions, observations, and summaries
+ */
+export class SessionSearch {
+  private db: Database.Database;
+
+  constructor(dbPath?: string) {
+    if (!dbPath) {
+      ensureDir(DATA_DIR);
+      dbPath = DB_PATH;
+    }
+    this.db = new Database(dbPath);
+    this.db.pragma('journal_mode = WAL');
+
+    // Ensure FTS tables exist
+    this.ensureFTSTables();
+  }
+
+  /**
+   * Ensure FTS5 tables exist (inline migration)
+   */
+  private ensureFTSTables(): void {
+    try {
+      // Check if FTS tables already exist
+      const tables = this.db.prepare("SELECT name FROM sqlite_master WHERE type='table' AND name LIKE '%_fts'").all() as any[];
+      const hasFTS = tables.some((t: any) => t.name === 'observations_fts' || t.name === 'session_summaries_fts');
+
+      if (hasFTS) {
+        // Already migrated
+        return;
+      }
+
+      console.error('[SessionSearch] Creating FTS5 tables...');
+
+      // Create observations_fts virtual table
+      this.db.exec(`
+        CREATE VIRTUAL TABLE IF NOT EXISTS observations_fts USING fts5(
+          title,
+          subtitle,
+          narrative,
+          text,
+          facts,
+          concepts,
+          content='observations',
+          content_rowid='id'
+        );
+      `);
+
+      // Populate with existing data
+      this.db.exec(`
+        INSERT INTO observations_fts(rowid, title, subtitle, narrative, text, facts, concepts)
+        SELECT id, title, subtitle, narrative, text, facts, concepts
+        FROM observations;
+      `);
+
+      // Create triggers for observations
+      this.db.exec(`
+        CREATE TRIGGER IF NOT EXISTS observations_ai AFTER INSERT ON observations BEGIN
+          INSERT INTO observations_fts(rowid, title, subtitle, narrative, text, facts, concepts)
+          VALUES (new.id, new.title, new.subtitle, new.narrative, new.text, new.facts, new.concepts);
+        END;
+
+        CREATE TRIGGER IF NOT EXISTS observations_ad AFTER DELETE ON observations BEGIN
+          INSERT INTO observations_fts(observations_fts, rowid, title, subtitle, narrative, text, facts, concepts)
+          VALUES('delete', old.id, old.title, old.subtitle, old.narrative, old.text, old.facts, old.concepts);
+        END;
+
+        CREATE TRIGGER IF NOT EXISTS observations_au AFTER UPDATE ON observations BEGIN
+          INSERT INTO observations_fts(observations_fts, rowid, title, subtitle, narrative, text, facts, concepts)
+          VALUES('delete', old.id, old.title, old.subtitle, old.narrative, old.text, old.facts, old.concepts);
+          INSERT INTO observations_fts(rowid, title, subtitle, narrative, text, facts, concepts)
+          VALUES (new.id, new.title, new.subtitle, new.narrative, new.text, new.facts, new.concepts);
+        END;
+      `);
+
+      // Create session_summaries_fts virtual table
+      this.db.exec(`
+        CREATE VIRTUAL TABLE IF NOT EXISTS session_summaries_fts USING fts5(
+          request,
+          investigated,
+          learned,
+          completed,
+          next_steps,
+          notes,
+          content='session_summaries',
+          content_rowid='id'
+        );
+      `);
+
+      // Populate with existing data
+      this.db.exec(`
+        INSERT INTO session_summaries_fts(rowid, request, investigated, learned, completed, next_steps, notes)
+        SELECT id, request, investigated, learned, completed, next_steps, notes
+        FROM session_summaries;
+      `);
+
+      // Create triggers for session_summaries
+      this.db.exec(`
+        CREATE TRIGGER IF NOT EXISTS session_summaries_ai AFTER INSERT ON session_summaries BEGIN
+          INSERT INTO session_summaries_fts(rowid, request, investigated, learned, completed, next_steps, notes)
+          VALUES (new.id, new.request, new.investigated, new.learned, new.completed, new.next_steps, new.notes);
+        END;
+
+        CREATE TRIGGER IF NOT EXISTS session_summaries_ad AFTER DELETE ON session_summaries BEGIN
+          INSERT INTO session_summaries_fts(session_summaries_fts, rowid, request, investigated, learned, completed, next_steps, notes)
+          VALUES('delete', old.id, old.request, old.investigated, old.learned, old.completed, old.next_steps, old.notes);
+        END;
+
+        CREATE TRIGGER IF NOT EXISTS session_summaries_au AFTER UPDATE ON session_summaries BEGIN
+          INSERT INTO session_summaries_fts(session_summaries_fts, rowid, request, investigated, learned, completed, next_steps, notes)
+          VALUES('delete', old.id, old.request, old.investigated, old.learned, old.completed, old.next_steps, old.notes);
+          INSERT INTO session_summaries_fts(rowid, request, investigated, learned, completed, next_steps, notes)
+          VALUES (new.id, new.request, new.investigated, new.learned, new.completed, new.next_steps, new.notes);
+        END;
+      `);
+
+      console.error('[SessionSearch] FTS5 tables created successfully');
+    } catch (error: any) {
+      console.error('[SessionSearch] FTS migration error:', error.message);
+    }
+  }
+
+  /**
+   * Escape FTS5 special characters in user input
+   */
+  private escapeFTS5(text: string): string {
+    // FTS5 special characters: " * ( ) AND OR NOT
+    // For safety, we'll wrap the entire query in quotes for phrase search
+    // or let advanced users pass boolean operators directly
+    return text;
+  }
+
+  /**
+   * Build WHERE clause for structured filters
+   */
+  private buildFilterClause(
+    filters: SearchFilters,
+    params: any[],
+    tableAlias: string = 'o'
+  ): string {
+    const conditions: string[] = [];
+
+    // Project filter
+    if (filters.project) {
+      conditions.push(`${tableAlias}.project = ?`);
+      params.push(filters.project);
+    }
+
+    // Type filter (for observations only)
+    if (filters.type) {
+      if (Array.isArray(filters.type)) {
+        const placeholders = filters.type.map(() => '?').join(',');
+        conditions.push(`${tableAlias}.type IN (${placeholders})`);
+        params.push(...filters.type);
+      } else {
+        conditions.push(`${tableAlias}.type = ?`);
+        params.push(filters.type);
+      }
+    }
+
+    // Date range filter
+    if (filters.dateRange) {
+      const { start, end } = filters.dateRange;
+      if (start) {
+        const startEpoch = typeof start === 'number' ? start : new Date(start).getTime();
+        conditions.push(`${tableAlias}.created_at_epoch >= ?`);
+        params.push(startEpoch);
+      }
+      if (end) {
+        const endEpoch = typeof end === 'number' ? end : new Date(end).getTime();
+        conditions.push(`${tableAlias}.created_at_epoch <= ?`);
+        params.push(endEpoch);
+      }
+    }
+
+    // Concepts filter (JSON array search)
+    if (filters.concepts) {
+      const concepts = Array.isArray(filters.concepts) ? filters.concepts : [filters.concepts];
+      const conceptConditions = concepts.map(() => {
+        return `EXISTS (SELECT 1 FROM json_each(${tableAlias}.concepts) WHERE value = ?)`;
+      });
+      if (conceptConditions.length > 0) {
+        conditions.push(`(${conceptConditions.join(' OR ')})`);
+        params.push(...concepts);
+      }
+    }
+
+    // Files filter (JSON array search)
+    if (filters.files) {
+      const files = Array.isArray(filters.files) ? filters.files : [filters.files];
+      const fileConditions = files.map(() => {
+        return `(
+          EXISTS (SELECT 1 FROM json_each(${tableAlias}.files_read) WHERE value LIKE ?)
+          OR EXISTS (SELECT 1 FROM json_each(${tableAlias}.files_modified) WHERE value LIKE ?)
+        )`;
+      });
+      if (fileConditions.length > 0) {
+        conditions.push(`(${fileConditions.join(' OR ')})`);
+        files.forEach(file => {
+          params.push(`%${file}%`, `%${file}%`);
+        });
+      }
+    }
+
+    return conditions.length > 0 ? conditions.join(' AND ') : '';
+  }
+
+  /**
+   * Build ORDER BY clause
+   */
+  private buildOrderClause(orderBy: SearchOptions['orderBy'] = 'relevance', hasFTS: boolean = true, ftsTable: string = 'observations_fts'): string {
+    switch (orderBy) {
+      case 'relevance':
+        return hasFTS ? `ORDER BY ${ftsTable}.rank ASC` : 'ORDER BY o.created_at_epoch DESC';
+      case 'date_desc':
+        return 'ORDER BY o.created_at_epoch DESC';
+      case 'date_asc':
+        return 'ORDER BY o.created_at_epoch ASC';
+      default:
+        return 'ORDER BY o.created_at_epoch DESC';
+    }
+  }
+
+  /**
+   * Search observations using FTS5 full-text search
+   */
+  searchObservations(query: string, options: SearchOptions = {}): ObservationSearchResult[] {
+    const params: any[] = [];
+    const { limit = 50, offset = 0, orderBy = 'relevance', ...filters } = options;
+
+    // Build FTS5 match query
+    const ftsQuery = this.escapeFTS5(query);
+    params.push(ftsQuery);
+
+    // Build filter conditions
+    const filterClause = this.buildFilterClause(filters, params, 'o');
+    const whereClause = filterClause ? `AND ${filterClause}` : '';
+
+    // Build ORDER BY
+    const orderClause = this.buildOrderClause(orderBy, true);
+
+    // Main query with FTS5
+    const sql = `
+      SELECT
+        o.*,
+        observations_fts.rank as rank
+      FROM observations o
+      JOIN observations_fts ON o.id = observations_fts.rowid
+      WHERE observations_fts MATCH ?
+      ${whereClause}
+      ${orderClause}
+      LIMIT ? OFFSET ?
+    `;
+
+    params.push(limit, offset);
+
+    const results = this.db.prepare(sql).all(...params) as ObservationSearchResult[];
+
+    // Normalize rank to score (0-1, higher is better)
+    if (results.length > 0) {
+      const minRank = Math.min(...results.map(r => r.rank || 0));
+      const maxRank = Math.max(...results.map(r => r.rank || 0));
+      const range = maxRank - minRank || 1;
+
+      results.forEach(r => {
+        if (r.rank !== undefined) {
+          // Invert rank (lower rank = better match) and normalize to 0-1
+          r.score = 1 - ((r.rank - minRank) / range);
+        }
+      });
+    }
+
+    return results;
+  }
+
+  /**
+   * Search session summaries using FTS5 full-text search
+   */
+  searchSessions(query: string, options: SearchOptions = {}): SessionSummarySearchResult[] {
+    const params: any[] = [];
+    const { limit = 50, offset = 0, orderBy = 'relevance', ...filters } = options;
+
+    // Build FTS5 match query
+    const ftsQuery = this.escapeFTS5(query);
+    params.push(ftsQuery);
+
+    // Build filter conditions (without type filter - not applicable to summaries)
+    const filterOptions = { ...filters };
+    delete filterOptions.type;
+    const filterClause = this.buildFilterClause(filterOptions, params, 's');
+    const whereClause = filterClause ? `AND ${filterClause}` : '';
+
+    // Note: session_summaries don't have files_read/files_modified in the same way
+    // We'll need to adjust the filter clause
+    const adjustedWhereClause = whereClause.replace(/files_read/g, 'files_read').replace(/files_modified/g, 'files_edited');
+
+    // Build ORDER BY
+    const orderClause = orderBy === 'relevance'
+      ? 'ORDER BY session_summaries_fts.rank ASC'
+      : orderBy === 'date_asc'
+      ? 'ORDER BY s.created_at_epoch ASC'
+      : 'ORDER BY s.created_at_epoch DESC';
+
+    // Main query with FTS5
+    const sql = `
+      SELECT
+        s.*,
+        session_summaries_fts.rank as rank
+      FROM session_summaries s
+      JOIN session_summaries_fts ON s.id = session_summaries_fts.rowid
+      WHERE session_summaries_fts MATCH ?
+      ${adjustedWhereClause}
+      ${orderClause}
+      LIMIT ? OFFSET ?
+    `;
+
+    params.push(limit, offset);
+
+    const results = this.db.prepare(sql).all(...params) as SessionSummarySearchResult[];
+
+    // Normalize rank to score
+    if (results.length > 0) {
+      const minRank = Math.min(...results.map(r => r.rank || 0));
+      const maxRank = Math.max(...results.map(r => r.rank || 0));
+      const range = maxRank - minRank || 1;
+
+      results.forEach(r => {
+        if (r.rank !== undefined) {
+          r.score = 1 - ((r.rank - minRank) / range);
+        }
+      });
+    }
+
+    return results;
+  }
+
+  /**
+   * Find observations by concept tag
+   */
+  findByConcept(concept: string, filters: SearchFilters = {}): ObservationSearchResult[] {
+    const params: any[] = [];
+
+    // Add concept to filters
+    const conceptFilters = { ...filters, concepts: concept };
+    const filterClause = this.buildFilterClause(conceptFilters, params, 'o');
+
+    const sql = `
+      SELECT o.*
+      FROM observations o
+      WHERE ${filterClause}
+      ORDER BY o.created_at_epoch DESC
+    `;
+
+    return this.db.prepare(sql).all(...params) as ObservationSearchResult[];
+  }
+
+  /**
+   * Find observations and summaries by file path
+   */
+  findByFile(filePath: string, filters: SearchFilters = {}): {
+    observations: ObservationSearchResult[];
+    sessions: SessionSummarySearchResult[];
+  } {
+    const params: any[] = [];
+
+    // Add file to filters
+    const fileFilters = { ...filters, files: filePath };
+    const filterClause = this.buildFilterClause(fileFilters, params, 'o');
+
+    const observationsSql = `
+      SELECT o.*
+      FROM observations o
+      WHERE ${filterClause}
+      ORDER BY o.created_at_epoch DESC
+    `;
+
+    const observations = this.db.prepare(observationsSql).all(...params) as ObservationSearchResult[];
+
+    // For session summaries, search files_read and files_edited
+    const sessionParams: any[] = [];
+    const sessionFilters = { ...filters };
+    delete sessionFilters.type; // Remove type filter for sessions
+
+    const baseConditions: string[] = [];
+    if (sessionFilters.project) {
+      baseConditions.push('s.project = ?');
+      sessionParams.push(sessionFilters.project);
+    }
+
+    if (sessionFilters.dateRange) {
+      const { start, end } = sessionFilters.dateRange;
+      if (start) {
+        const startEpoch = typeof start === 'number' ? start : new Date(start).getTime();
+        baseConditions.push('s.created_at_epoch >= ?');
+        sessionParams.push(startEpoch);
+      }
+      if (end) {
+        const endEpoch = typeof end === 'number' ? end : new Date(end).getTime();
+        baseConditions.push('s.created_at_epoch <= ?');
+        sessionParams.push(endEpoch);
+      }
+    }
+
+    // File condition
+    baseConditions.push(`(
+      EXISTS (SELECT 1 FROM json_each(s.files_read) WHERE value LIKE ?)
+      OR EXISTS (SELECT 1 FROM json_each(s.files_edited) WHERE value LIKE ?)
+    )`);
+    sessionParams.push(`%${filePath}%`, `%${filePath}%`);
+
+    const sessionsSql = `
+      SELECT s.*
+      FROM session_summaries s
+      WHERE ${baseConditions.join(' AND ')}
+      ORDER BY s.created_at_epoch DESC
+    `;
+
+    const sessions = this.db.prepare(sessionsSql).all(...sessionParams) as SessionSummarySearchResult[];
+
+    return { observations, sessions };
+  }
+
+  /**
+   * Find observations by type
+   */
+  findByType(
+    type: ObservationRow['type'] | ObservationRow['type'][],
+    filters: SearchFilters = {}
+  ): ObservationSearchResult[] {
+    const params: any[] = [];
+
+    // Add type to filters
+    const typeFilters = { ...filters, type };
+    const filterClause = this.buildFilterClause(typeFilters, params, 'o');
+
+    const sql = `
+      SELECT o.*
+      FROM observations o
+      WHERE ${filterClause}
+      ORDER BY o.created_at_epoch DESC
+    `;
+
+    return this.db.prepare(sql).all(...params) as ObservationSearchResult[];
+  }
+
+  /**
+   * Advanced search combining FTS5 and structured filters
+   */
+  advancedSearch(options: {
+    textQuery?: string;
+    searchSessions?: boolean;
+  } & SearchOptions): {
+    observations: ObservationSearchResult[];
+    sessions: SessionSummarySearchResult[];
+  } {
+    const { textQuery, searchSessions = true, ...searchOptions } = options;
+
+    let observations: ObservationSearchResult[] = [];
+    let sessions: SessionSummarySearchResult[] = [];
+
+    if (textQuery) {
+      // Use FTS5 search
+      observations = this.searchObservations(textQuery, searchOptions);
+      if (searchSessions) {
+        sessions = this.searchSessions(textQuery, searchOptions);
+      }
+    } else {
+      // Pure structured query (no FTS)
+      const params: any[] = [];
+      const filterClause = this.buildFilterClause(searchOptions, params, 'o');
+
+      if (filterClause) {
+        const obsSql = `
+          SELECT o.*
+          FROM observations o
+          WHERE ${filterClause}
+          ${this.buildOrderClause(searchOptions.orderBy, false)}
+          LIMIT ? OFFSET ?
+        `;
+        params.push(searchOptions.limit || 50, searchOptions.offset || 0);
+        observations = this.db.prepare(obsSql).all(...params) as ObservationSearchResult[];
+      }
+
+      if (searchSessions) {
+        const sessionParams: any[] = [];
+        const sessionFilters = { ...searchOptions };
+        delete sessionFilters.type;
+        const sessionFilterClause = this.buildFilterClause(sessionFilters, sessionParams, 's');
+
+        if (sessionFilterClause) {
+          const sessSql = `
+            SELECT s.*
+            FROM session_summaries s
+            WHERE ${sessionFilterClause}
+            ORDER BY s.created_at_epoch DESC
+            LIMIT ? OFFSET ?
+          `;
+          sessionParams.push(searchOptions.limit || 50, searchOptions.offset || 0);
+          sessions = this.db.prepare(sessSql).all(...sessionParams) as SessionSummarySearchResult[];
+        }
+      }
+    }
+
+    return { observations, sessions };
+  }
+
+  /**
+   * Close the database connection
+   */
+  close(): void {
+    this.db.close();
+  }
+}

src/services/sqlite/SessionStore.ts

@@ -3,11 +3,10 @@ import { DATA_DIR, DB_PATH, ensureDir } from '../../shared/paths.js';
 import { logger } from '../../utils/logger.js';
 
 /**
- * Lightweight database interface for hooks
- * Provides simple, synchronous operations for hook commands
- * No complex logic - just basic CRUD operations
+ * Session data store for SDK sessions, observations, and summaries
+ * Provides simple, synchronous CRUD operations for session-based memory
  */
-export class HooksDatabase {
+export class SessionStore {
   private db: Database;
 
   constructor() {
@@ -38,10 +37,10 @@ export class HooksDatabase {
 
       if (!hasWorkerPort) {
         this.db.exec('ALTER TABLE sdk_sessions ADD COLUMN worker_port INTEGER');
-        console.error('[HooksDatabase] Added worker_port column to sdk_sessions table');
+        console.error('[SessionStore] Added worker_port column to sdk_sessions table');
       }
     } catch (error: any) {
-      console.error('[HooksDatabase] Migration error:', error.message);
+      console.error('[SessionStore] Migration error:', error.message);
     }
   }
 
@@ -56,7 +55,7 @@ export class HooksDatabase {
 
       if (!hasPromptCounter) {
         this.db.exec('ALTER TABLE sdk_sessions ADD COLUMN prompt_counter INTEGER DEFAULT 0');
-        console.error('[HooksDatabase] Added prompt_counter column to sdk_sessions table');
+        console.error('[SessionStore] Added prompt_counter column to sdk_sessions table');
       }
 
       // Check observations for prompt_number
@@ -65,7 +64,7 @@ export class HooksDatabase {
 
       if (!obsHasPromptNumber) {
         this.db.exec('ALTER TABLE observations ADD COLUMN prompt_number INTEGER');
-        console.error('[HooksDatabase] Added prompt_number column to observations table');
+        console.error('[SessionStore] Added prompt_number column to observations table');
       }
 
       // Check session_summaries for prompt_number
@@ -74,7 +73,7 @@ export class HooksDatabase {
 
       if (!sumHasPromptNumber) {
         this.db.exec('ALTER TABLE session_summaries ADD COLUMN prompt_number INTEGER');
-        console.error('[HooksDatabase] Added prompt_number column to session_summaries table');
+        console.error('[SessionStore] Added prompt_number column to session_summaries table');
       }
 
       // Remove UNIQUE constraint on session_summaries.sdk_session_id
@@ -83,7 +82,7 @@ export class HooksDatabase {
       const hasUniqueConstraint = (summariesIndexes as any[]).some((idx: any) => idx.unique === 1);
 
     } catch (error: any) {
-      console.error('[HooksDatabase] Prompt tracking migration error:', error.message);
+      console.error('[SessionStore] Prompt tracking migration error:', error.message);
     }
   }
 
@@ -101,7 +100,7 @@ export class HooksDatabase {
         return;
       }
 
-      console.error('[HooksDatabase] Removing UNIQUE constraint from session_summaries.sdk_session_id...');
+      console.error('[SessionStore] Removing UNIQUE constraint from session_summaries.sdk_session_id...');
 
       // Begin transaction
       this.db.exec('BEGIN TRANSACTION');
@@ -153,14 +152,14 @@ export class HooksDatabase {
         // Commit transaction
         this.db.exec('COMMIT');
 
-        console.error('[HooksDatabase] Successfully removed UNIQUE constraint from session_summaries.sdk_session_id');
+        console.error('[SessionStore] Successfully removed UNIQUE constraint from session_summaries.sdk_session_id');
       } catch (error: any) {
         // Rollback on error
         this.db.exec('ROLLBACK');
         throw error;
       }
     } catch (error: any) {
-      console.error('[HooksDatabase] Migration error (remove UNIQUE constraint):', error.message);
+      console.error('[SessionStore] Migration error (remove UNIQUE constraint):', error.message);
     }
   }
 
@@ -178,7 +177,7 @@ export class HooksDatabase {
         return;
       }
 
-      console.error('[HooksDatabase] Adding hierarchical fields to observations table...');
+      console.error('[SessionStore] Adding hierarchical fields to observations table...');
 
       // Add new columns
       this.db.exec(`
@@ -191,9 +190,9 @@ export class HooksDatabase {
         ALTER TABLE observations ADD COLUMN files_modified TEXT;
       `);
 
-      console.error('[HooksDatabase] Successfully added hierarchical fields to observations table');
+      console.error('[SessionStore] Successfully added hierarchical fields to observations table');
     } catch (error: any) {
-      console.error('[HooksDatabase] Migration error (add hierarchical fields):', error.message);
+      console.error('[SessionStore] Migration error (add hierarchical fields):', error.message);
     }
   }
 
@@ -212,7 +211,7 @@ export class HooksDatabase {
         return;
       }
 
-      console.error('[HooksDatabase] Making observations.text nullable...');
+      console.error('[SessionStore] Making observations.text nullable...');
 
       // Begin transaction
       this.db.exec('BEGIN TRANSACTION');
@@ -266,14 +265,14 @@ export class HooksDatabase {
         // Commit transaction
         this.db.exec('COMMIT');
 
-        console.error('[HooksDatabase] Successfully made observations.text nullable');
+        console.error('[SessionStore] Successfully made observations.text nullable');
       } catch (error: any) {
         // Rollback on error
         this.db.exec('ROLLBACK');
         throw error;
       }
     } catch (error: any) {
-      console.error('[HooksDatabase] Migration error (make text nullable):', error.message);
+      console.error('[SessionStore] Migration error (make text nullable):', error.message);
     }
   }
 

src/services/sqlite/index.ts

@@ -1,8 +1,11 @@
 // Export main components
 export { DatabaseManager, getDatabase, initializeDatabase } from './Database.js';
 
-// Export hooks database
-export { HooksDatabase } from './HooksDatabase.js';
+// Export session store (CRUD operations for sessions, observations, summaries)
+export { SessionStore } from './SessionStore.js';
+
+// Export session search (FTS5 and structured search)
+export { SessionSearch } from './SessionSearch.js';
 
 // Export types
 export * from './types.js';

src/services/sqlite/migrations.ts

@@ -362,6 +362,115 @@ export const migration005: Migration = {
   }
 };
 
+/**
+ * Migration 006 - Add FTS5 full-text search tables
+ * Creates virtual tables for fast text search on observations and session_summaries
+ */
+export const migration006: Migration = {
+  version: 6,
+  up: (db: Database) => {
+    // FTS5 virtual table for observations
+    // Note: This assumes the hierarchical fields (title, subtitle, etc.) already exist
+    // from the inline migrations in SessionStore constructor
+    db.run(`
+      CREATE VIRTUAL TABLE IF NOT EXISTS observations_fts USING fts5(
+        title,
+        subtitle,
+        narrative,
+        text,
+        facts,
+        concepts,
+        content='observations',
+        content_rowid='id'
+      );
+    `);
+
+    // Populate FTS table with existing data
+    db.run(`
+      INSERT INTO observations_fts(rowid, title, subtitle, narrative, text, facts, concepts)
+      SELECT id, title, subtitle, narrative, text, facts, concepts
+      FROM observations;
+    `);
+
+    // Triggers to keep observations_fts in sync
+    db.run(`
+      CREATE TRIGGER IF NOT EXISTS observations_ai AFTER INSERT ON observations BEGIN
+        INSERT INTO observations_fts(rowid, title, subtitle, narrative, text, facts, concepts)
+        VALUES (new.id, new.title, new.subtitle, new.narrative, new.text, new.facts, new.concepts);
+      END;
+
+      CREATE TRIGGER IF NOT EXISTS observations_ad AFTER DELETE ON observations BEGIN
+        INSERT INTO observations_fts(observations_fts, rowid, title, subtitle, narrative, text, facts, concepts)
+        VALUES('delete', old.id, old.title, old.subtitle, old.narrative, old.text, old.facts, old.concepts);
+      END;
+
+      CREATE TRIGGER IF NOT EXISTS observations_au AFTER UPDATE ON observations BEGIN
+        INSERT INTO observations_fts(observations_fts, rowid, title, subtitle, narrative, text, facts, concepts)
+        VALUES('delete', old.id, old.title, old.subtitle, old.narrative, old.text, old.facts, old.concepts);
+        INSERT INTO observations_fts(rowid, title, subtitle, narrative, text, facts, concepts)
+        VALUES (new.id, new.title, new.subtitle, new.narrative, new.text, new.facts, new.concepts);
+      END;
+    `);
+
+    // FTS5 virtual table for session_summaries
+    db.run(`
+      CREATE VIRTUAL TABLE IF NOT EXISTS session_summaries_fts USING fts5(
+        request,
+        investigated,
+        learned,
+        completed,
+        next_steps,
+        notes,
+        content='session_summaries',
+        content_rowid='id'
+      );
+    `);
+
+    // Populate FTS table with existing data
+    db.run(`
+      INSERT INTO session_summaries_fts(rowid, request, investigated, learned, completed, next_steps, notes)
+      SELECT id, request, investigated, learned, completed, next_steps, notes
+      FROM session_summaries;
+    `);
+
+    // Triggers to keep session_summaries_fts in sync
+    db.run(`
+      CREATE TRIGGER IF NOT EXISTS session_summaries_ai AFTER INSERT ON session_summaries BEGIN
+        INSERT INTO session_summaries_fts(rowid, request, investigated, learned, completed, next_steps, notes)
+        VALUES (new.id, new.request, new.investigated, new.learned, new.completed, new.next_steps, new.notes);
+      END;
+
+      CREATE TRIGGER IF NOT EXISTS session_summaries_ad AFTER DELETE ON session_summaries BEGIN
+        INSERT INTO session_summaries_fts(session_summaries_fts, rowid, request, investigated, learned, completed, next_steps, notes)
+        VALUES('delete', old.id, old.request, old.investigated, old.learned, old.completed, old.next_steps, old.notes);
+      END;
+
+      CREATE TRIGGER IF NOT EXISTS session_summaries_au AFTER UPDATE ON session_summaries BEGIN
+        INSERT INTO session_summaries_fts(session_summaries_fts, rowid, request, investigated, learned, completed, next_steps, notes)
+        VALUES('delete', old.id, old.request, old.investigated, old.learned, old.completed, old.next_steps, old.notes);
+        INSERT INTO session_summaries_fts(rowid, request, investigated, learned, completed, next_steps, notes)
+        VALUES (new.id, new.request, new.investigated, new.learned, new.completed, new.next_steps, new.notes);
+      END;
+    `);
+
+    console.log('✅ Created FTS5 virtual tables and triggers for full-text search');
+  },
+
+  down: (db: Database) => {
+    db.run(`
+      DROP TRIGGER IF EXISTS observations_au;
+      DROP TRIGGER IF EXISTS observations_ad;
+      DROP TRIGGER IF EXISTS observations_ai;
+      DROP TABLE IF EXISTS observations_fts;
+
+      DROP TRIGGER IF EXISTS session_summaries_au;
+      DROP TRIGGER IF EXISTS session_summaries_ad;
+      DROP TRIGGER IF EXISTS session_summaries_ai;
+      DROP TABLE IF EXISTS session_summaries_fts;
+    `);
+  }
+};
+
 /**
  * All migrations in order
  */
@@ -370,5 +479,6 @@ export const migrations: Migration[] = [
   migration002,
   migration003,
   migration004,
-  migration005
+  migration005,
+  migration006
 ];

src/services/sqlite/types.ts

@@ -182,3 +182,88 @@ export function normalizeTimestamp(timestamp: string | Date | number | undefined
     epoch: date.getTime()
   };
 }
+
+/**
+ * SDK Hooks Database Types
+ */
+export interface SDKSessionRow {
+  id: number;
+  claude_session_id: string;
+  sdk_session_id: string | null;
+  project: string;
+  user_prompt: string | null;
+  started_at: string;
+  started_at_epoch: number;
+  completed_at: string | null;
+  completed_at_epoch: number | null;
+  status: 'active' | 'completed' | 'failed';
+  worker_port?: number;
+  prompt_counter?: number;
+}
+
+export interface ObservationRow {
+  id: number;
+  sdk_session_id: string;
+  project: string;
+  text: string | null;
+  type: 'decision' | 'bugfix' | 'feature' | 'refactor' | 'discovery' | 'change';
+  title: string | null;
+  subtitle: string | null;
+  facts: string | null; // JSON array
+  narrative: string | null;
+  concepts: string | null; // JSON array
+  files_read: string | null; // JSON array
+  files_modified: string | null; // JSON array
+  prompt_number: number | null;
+  created_at: string;
+  created_at_epoch: number;
+}
+
+export interface SessionSummaryRow {
+  id: number;
+  sdk_session_id: string;
+  project: string;
+  request: string | null;
+  investigated: string | null;
+  learned: string | null;
+  completed: string | null;
+  next_steps: string | null;
+  files_read: string | null; // JSON array
+  files_edited: string | null; // JSON array
+  notes: string | null;
+  prompt_number: number | null;
+  created_at: string;
+  created_at_epoch: number;
+}
+
+/**
+ * Search and Filter Types
+ */
+export interface DateRange {
+  start?: string | number; // ISO string or epoch
+  end?: string | number;   // ISO string or epoch
+}
+
+export interface SearchFilters {
+  project?: string;
+  type?: ObservationRow['type'] | ObservationRow['type'][];
+  concepts?: string | string[];
+  files?: string | string[];
+  dateRange?: DateRange;
+}
+
+export interface SearchOptions extends SearchFilters {
+  limit?: number;
+  offset?: number;
+  orderBy?: 'relevance' | 'date_desc' | 'date_asc';
+}
+
+export interface ObservationSearchResult extends ObservationRow {
+  rank?: number; // FTS5 relevance score (lower is better)
+  score?: number; // Normalized score (higher is better, 0-1)
+}
+
+export interface SessionSummarySearchResult extends SessionSummaryRow {
+  rank?: number; // FTS5 relevance score (lower is better)
+  score?: number; // Normalized score (higher is better, 0-1)
+}