/**
* Metadata inspection tools for IBM DB2i MCP Server
*/
import {
listSchemas,
listTables,
describeTable,
listViews,
listIndexes,
getTableConstraints,
} from '../db/queries.js';
import { loadConfig, getDefaultSchema } from '../config.js';
/**
* Standard success/error result type for metadata tools
*/
type ToolResult<T> =
| { success: true; data: T[]; count: number }
| { success: false; error: string };
/**
* Wraps an async function with standard error handling
*/
async function withErrorHandling<T>(
fn: () => Promise<T[]>
): Promise<ToolResult<T>> {
try {
const data = await fn();
return { success: true, data, count: data.length };
} catch (error) {
const message = error instanceof Error ? error.message : 'Unknown error occurred';
return { success: false, error: message };
}
}
/**
* Get schema to use - either from input or from default config
*/
function resolveSchema(inputSchema?: string): string {
if (inputSchema) {
return inputSchema;
}
const config = loadConfig();
const defaultSchema = getDefaultSchema(config);
if (!defaultSchema) {
throw new Error('Schema is required. Either provide it as a parameter or set DB2I_SCHEMA environment variable.');
}
return defaultSchema;
}
// ============================================================================
// List Schemas Tool
// ============================================================================
export function listSchemasTool(input: { filter?: string }): Promise<ToolResult<{
schema_name: string;
schema_text: string | null;
}>> {
return withErrorHandling(() => listSchemas(input.filter));
}
// ============================================================================
// List Tables Tool
// ============================================================================
export function listTablesTool(input: { schema?: string; filter?: string }): Promise<ToolResult<{
table_name: string;
table_type: string;
table_text: string | null;
}>> {
return withErrorHandling(() => {
const schema = resolveSchema(input.schema);
return listTables(schema, input.filter);
});
}
// ============================================================================
// Describe Table Tool
// ============================================================================
export function describeTableTool(input: { schema?: string; table: string }): Promise<ToolResult<{
column_name: string;
ordinal_position: number;
data_type: string;
length: number | null;
numeric_scale: number | null;
is_nullable: string;
column_default: string | null;
column_text: string | null;
system_column_name: string;
ccsid: number | null;
}>> {
return withErrorHandling(() => {
const schema = resolveSchema(input.schema);
return describeTable(schema, input.table);
});
}
// ============================================================================
// List Views Tool
// ============================================================================
export function listViewsTool(input: { schema?: string; filter?: string }): Promise<ToolResult<{
view_name: string;
view_text: string | null;
}>> {
return withErrorHandling(() => {
const schema = resolveSchema(input.schema);
return listViews(schema, input.filter);
});
}
// ============================================================================
// List Indexes Tool
// ============================================================================
export function listIndexesTool(input: { schema?: string; table: string }): Promise<ToolResult<{
index_name: string;
index_schema: string;
is_unique: string;
column_names: string;
}>> {
return withErrorHandling(() => {
const schema = resolveSchema(input.schema);
return listIndexes(schema, input.table);
});
}
// ============================================================================
// Get Table Constraints Tool
// ============================================================================
export function getTableConstraintsTool(input: { schema?: string; table: string }): Promise<ToolResult<{
constraint_name: string;
constraint_type: string;
column_name: string;
ordinal_position: number;
referenced_table_schema: string | null;
referenced_table_name: string | null;
referenced_column_name: string | null;
}>> {
return withErrorHandling(() => {
const schema = resolveSchema(input.schema);
return getTableConstraints(schema, input.table);
});
}
