import { BaseTool } from './base.js';
import { ColumnInfo } from '../types.js';
import { ParameterValidator } from '../validation.js';
export class DescribeTableTool extends BaseTool {
getName(): string {
return 'describe_table';
}
getDescription(): string {
return 'Get detailed schema information for a specific table including columns, data types, and constraints';
}
getInputSchema(): any {
return {
type: 'object',
properties: {
table_name: {
type: 'string',
description: 'Name of the table to describe',
},
schema: {
type: 'string',
description: 'Schema name (optional, defaults to dbo)',
default: 'dbo',
},
},
required: ['table_name'],
};
}
async execute(params: { table_name: string; schema?: string }): Promise<ColumnInfo[]> {
const validatedParams = ParameterValidator.validateTableDescriptionParameters(params);
const { table_name, schema } = validatedParams;
const escapedTableName = ParameterValidator.escapeIdentifier(table_name);
const escapedSchema = ParameterValidator.escapeIdentifier(schema);
const query = `
SELECT
TABLE_CATALOG as table_catalog,
TABLE_SCHEMA as table_schema,
TABLE_NAME as table_name,
COLUMN_NAME as column_name,
ORDINAL_POSITION as ordinal_position,
COLUMN_DEFAULT as column_default,
IS_NULLABLE as is_nullable,
DATA_TYPE as data_type,
CHARACTER_MAXIMUM_LENGTH as character_maximum_length,
CHARACTER_OCTET_LENGTH as character_octet_length,
NUMERIC_PRECISION as numeric_precision,
NUMERIC_PRECISION_RADIX as numeric_precision_radix,
NUMERIC_SCALE as numeric_scale,
DATETIME_PRECISION as datetime_precision
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = ${escapedTableName}
AND TABLE_SCHEMA = ${escapedSchema}
ORDER BY ORDINAL_POSITION
`;
return await this.executeSafeQuery<ColumnInfo>(query);
}
}
