Enhanced Knowledge Graph Memory Server

{ "phase": 4, "sprint": 7, "title": "Graph Algorithms: Path Finding", "priority": "MEDIUM", "effort": "6 hours", "status": "completed", "impact": "New capability: Find connections between entities; Answer 'how are X and Y related?'", "targetMetrics": { "shortestPath": { "target": "<50ms for 1000 nodes" }, "allPaths": { "target": "<200ms for 1000 nodes, maxLength=5" }, "pathReconstruction": { "target": "Include full entity and relation details" } }, "tasks": [ { "id": 1, "category": "Core", "description": "Implement Shortest Path Algorithm - Add shortestPath() method to GraphTraversal using BFS for unweighted graphs, return PathResult with entity path and relations traversed", "status": "completed", "estimatedHours": 2, "agent": "sonnet", "files": ["src/memory/core/GraphTraversal.ts"], "testCategories": [ "Find shortest path between connected entities", "Handle same source and target (length 0)", "Return null for disconnected entities", "Respect relation type filters", "Include relations in result" ], "acceptanceCriteria": [ "shortestPath(fromName, toName, options) method implemented", "Uses BFS for unweighted shortest path", "Returns PathResult with path[], relations[], length", "Returns null if no path exists", "Same entity returns path of length 0", "Respects TraversalOptions (relationTypes, direction, maxDepth)", "reconstructPath() helper builds full PathResult" ] }, { "id": 2, "category": "Core", "description": "Implement reconstructPath Helper - Add private method to rebuild path from BFS parent map, include full Entity objects and Relation objects in PathResult", "status": "completed", "estimatedHours": 1, "agent": "sonnet", "files": ["src/memory/core/GraphTraversal.ts"], "testCategories": [ "Reconstructs path correctly", "Includes all intermediate entities", "Includes all traversed relations" ], "acceptanceCriteria": [ "reconstructPath(from, to, parentMap) method implemented", "Returns PathResult with Entity[] not just names", "Includes Relation[] for edges traversed", "Handles hierarchy edges (no relation)", "Path order is correct (start to end)" ] }, { "id": 3, "category": "Core", "description": "Implement All Paths Algorithm - Add allPaths() method using DFS with backtracking, return all paths up to maxLength, limit results to prevent explosion", "status": "completed", "estimatedHours": 2, "agent": "sonnet", "files": ["src/memory/core/GraphTraversal.ts"], "testCategories": [ "Find all paths between entities", "Respect maxLength limit", "Handle cycles (visited set per path)", "Limit number of results", "Include relations in results" ], "acceptanceCriteria": [ "allPaths(fromName, toName, maxLength) method implemented", "Default maxLength = 5 to limit computation", "Uses DFS with backtracking", "Visited set is per-path (allows revisits on different paths)", "Returns PathResult[] sorted by length", "Maximum 100 paths returned to prevent explosion" ] }, { "id": 4, "category": "Tests", "description": "Create Path Finding Tests - Test shortest path and all paths with various graph structures and edge cases", "status": "completed", "estimatedHours": 1, "agent": "sonnet", "files": ["src/memory/__tests__/unit/core/GraphTraversal.test.ts"], "testCategories": [ "Shortest path in simple graph", "Shortest path with multiple options", "All paths with cycles", "No path exists", "Performance with large graphs" ], "acceptanceCriteria": [ "Test shortest path in linear graph", "Test shortest path with branching", "Test all paths finds multiple routes", "Test maxLength limits results", "Test no path returns null/empty", "Performance test < 50ms for 1000 nodes", "15+ new tests added" ] } ], "successCriteria": [ "shortestPath() finds optimal path between entities", "allPaths() finds all routes up to maxLength", "PathResult includes full Entity and Relation objects", "Performance meets targets for 1000-node graphs", "Edge cases handled (no path, same entity, cycles)" ], "filesModified": [ "src/memory/core/GraphTraversal.ts", "src/memory/__tests__/unit/core/GraphTraversal.test.ts" ], "filesCreated": [], "totalNewTests": 15, "totalEstimatedHours": 6, "dependencies": ["Sprint 6"], "notes": "Path finding is one of the most useful graph operations. shortestPath answers 'what is the closest connection between X and Y?' while allPaths shows 'all the ways X and Y are connected'. Both are essential for exploring knowledge graph relationships. The algorithms build on the BFS/DFS foundation from Sprint 6." }