# Write Metadata You can use the Write Metadata step to add new metadata to any existing metadata in the Pentaho Data Catalog that is already associated with specific data resources. You can add a description and tags to the data resource. You can also add metadata for any new data resources that your transformation may be adding to Data Catalog. The Write Metadata step includes options to identify, locate, and append the metadata associated with existing Resource IDs in the Data Catalog. For more information about accessing Pentaho Data Catalog in PDI, see [PDI and Data Catalog](/pdia-data-integration/9.3-data-integration/advanced-topics-pentaho-data-integration-overview/pdi-and-lumada-data-catalog-ldc.md). **Note:** This step is supported on the PDI engine but not on the Spark engine. Only CSV text file and Parquet data formats are currently supported. You must have role permissions in Data Catalog to read the data resources. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/pdi-transformation-steps-reference-overview/write-metadata.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.