Construct the OASIS query URL with your desired report name, start and end times, and query parameters.
Append resultformat=6 to the query string to request the response as a zipped CSV archive.
Send a GET request to http://oasis.caiso.com/oasisapi/SingleZip with your parameters.
Save the binary response body as a .zip file.
Extract the zip archive to obtain the CSV file(s) inside.
Parse the CSV using your preferred data tool, noting that CAISO CSVs typically include metadata rows before the data header.
Known gotchas
resultformat=6 returns zipped CSV; resultformat=5 returns XML — these are distinct formats and must not be confused; there is no resultformat=9 for this endpoint.
OASIS queries have time range limits; requests spanning too large a window will be rejected — break large date ranges into smaller chunks.
OASIS may be unavailable during scheduled maintenance windows; implement retry logic with appropriate backoff for production use.
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claude mcp add --transport http waymark https://mcp.waymark.network/mcp