Hey ​@Sandhya - ArcGIS geoprocessing tools operate on local imagery like raster datasets or mosaic datasets pointing to data on your local machine. You can alternatively work with remote imagery datasets through image services hosted in ArcGIS Online or Enterprise. You can also connect to imagery in cloud storage for these web services. You can then analyze this data using raster analytics tools in ArcGIS Online or Enterprise.

Planet does not offer ArcGIS image services or raster analytics tools that you can use in ArcGIS Pro, you would need to set this up yourself. Alternatively, Planet offers cloud-based raster analytics tools on our own Planet Insights Platform.

So, in order to do image processing in ArcGIS Pro without downloading imagery to your local machine, you have those two options:

1. You can use our APIs to order imagery to your own cloud storage or to move data into ArcGIS Online image collections. Once your Planet data is moved into ArcGIS, you can use the ArcGIS raster analytics tools. Note: this may require additional licensing from Esri.
   
   Pro: more extensive raster processing tools, fully integrated into ArcGIS ecosystem. Cons: Additional licensing; more complex data management.
    
2. Instead of downloading imagery to your computer or moving it to ArcGIS, you can host imagery in data collections on Planet Insights Platform. When you do this - you can then stream data through OGC services into ArcGIS Pro. We offer a smaller set of server-side geoprocessing capabilities such as calculating spectral indices, applying masks, doing change analysis/multi temporal comparisons, multi-source data fusion. The way you do analysis - instead of running geoprocessing tools - you would write custom evalscripts and then copy/paste a WMTS URL and add it to your ArcGIS projects.
   
   Pros: Easier - less involved data management process, built on open standards for interoperability outside of ArcGIS. Cons: No direct access to pixel values from ArcGIS Pro - only streaming the visual output services, fewer advanced analysis options today compared to ArcGIS raster analytics tools, but options for many standard analysis.