See https://github.com/influxdata/openapi/pull/651/files

When the v1 /query API returns a chunked response, we should be including a partial parameter in the series results to indicate that there are more records to be streamed.

Edit: This issue is a bit more challenging than it may appear. The current buffering/streaming logic in the v1 query API code is not set up to emit such a parameter that is aware of records that have not been streamed to the response yet. This is because it currently flushes everything that has been buffered, if possible, before polling the input RecordBatchStream for more RecordBatches; in which case, the value of partial parameter may depend on record batches yet to be streamed.

Ultimately, to make this work, we likely need to change the underlying buffering/streaming logic.