find_neighbors
Query connected vertices in a NebulaGraph database to analyze relationships and explore graph structures by specifying a starting vertex and traversal depth.
Instructions
Find the neighbors of the specified vertex Args: vertex: The vertex ID to query space: The space to use depth: The depth of the query, default is 1 Returns: The neighbors of the specified vertex
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| vertex | Yes | ||
| space | Yes | ||
| depth | No |
Implementation Reference
- The handler function for the 'find_neighbors' MCP tool, decorated with @mcp.tool() for registration. It receives parameters and delegates to the helper resource function.
@mcp.tool() def find_neighbors(vertex: str, space: str, depth: int = 1) -> str: """Find the neighbors of the specified vertex Args: vertex: The vertex ID to query space: The space to use depth: The depth of the query, default is 1 Returns: The neighbors of the specified vertex """ return get_neighbors_resource(space, vertex, depth) - Core helper function implementing the neighbor query logic using NebulaGraph nGQL MATCH query to find vertices and edges connected to the given vertex up to specified depth.
@mcp.resource("neighbors://space/{space}/vertex/{vertex}/depth/{depth}") def get_neighbors_resource(space: str, vertex: str, depth: int) -> str: """Get the neighbors of the specified vertex Args: space: The space to use vertex: The vertex ID to query depth: The depth of the query Returns: The neighbors of the specified vertex """ pool = get_connection_pool() session = pool.get_session( os.getenv("NEBULA_USER", "root"), os.getenv("NEBULA_PASSWORD", "nebula") ) try: session.execute(f"USE {space}") query = f""" MATCH (u)-[e*1..{depth}]-(v) WHERE id(u) == "{vertex}" RETURN DISTINCT v, e """ result = session.execute(query) if result.is_succeeded(): if result.row_size() > 0: output = f"Vertex {vertex} neighbors (depth {depth}):\n\n" for i in range(result.row_size()): row = result.row_values(i) neighbor_vertex = row[0] edges = row[1] output += ( f"Neighbor Vertex:\n{neighbor_vertex}\nEdges:\n{edges}\n\n" ) return output return f"No neighbors found for vertex {vertex}" else: return f"Query failed: {result.error_msg()}" finally: session.release()