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When you build pipelines with the agent, much of the structure and logic is generated for you. Your role shifts from manually assembling each step to inspecting and verifying that each transformation behaves as expected. You can do this directly in the visual interface by opening gems and reviewing the data they produce.

How inspection works

Inspecting a pipeline typically involves the following:
  • Reviewing the pipeline as a whole.
  • Reviewing the logic inside a gem.
  • Reviewing the data output after that gem runs.
  • (Optionally) Examining the SQL behind a gem.
Inspection steps Prophecy provides a few tools to support this workflow:

Inspect the overall pipeline

Begin by reviewing the pipeline as a whole to understand how data flows through each step. On the pipeline canvas, look at:
  • The sequence of steps — how data moves from sources to final outputs.
  • Joins and branching paths — where datasets are combined or split.
  • Inputs and outputs — what each gem receives and produces.
  • Key transformation points — where filtering, aggregation, or enrichment occurs.
This high-level view helps you answer questions like:
  • Does the pipeline follow the intended logic from start to finish?
  • Are joins happening in the right place and in the right order?
  • Are there unnecessary or missing steps?
  • Does the final output reflect the transformations you expect?
Here are some examples of gems featured in the screenshot below:
  1. Table gems, which visualize your data sources.
  2. Reformat gems, which transforms one or more column names or values by using expressions and/or functions.
  3. Join gems, which combine data from two or more datasets based on a shared column value.
  4. Filter gems, which filter output rows based on defined criteria.
Generated pipeline

Inspect a pipeline step

To understand what a step is doing:
  1. Identify the gem you want to inspect on the canvas.
  2. Open the gem to review its configuration.
  3. Check how inputs are transformed:
    • joins and join conditions
    • filters and conditions
    • derived or reformatted columns
  4. If the gem includes expressions, review them using the visual expression builder.
Opening a gem helps you understand how the transformation is defined. For example, the screenshot below depicts a Filter gem that filters out rows where MONTHLY_PREMIUM is null or zero. Generated pipeline

Inspect results

After reviewing the logic, validate the output:
  1. Run the pipeline up to and including the gem.
  2. Open the result in the Data Explorer.
  3. Review:
    • rows and sample values
    • column names and types
    • schema changes from previous steps
If you need deeper insight into the data, use the Data Profile to check distributions, null values, and outliers. Inspecting results helps you confirm that the transformation behaves as expected. Data explorer with data analysis open

What to look for

When inspecting a pipeline step, focus on whether the output matches your expectations:
  • Did the number of rows change in the way you expected?
  • Were any rows unexpectedly dropped or duplicated?
  • Did the schema change correctly (new columns, renamed fields, type changes)?
  • Are there unexpected null values or missing data?
  • Do derived columns contain the correct values?
  • Do joins and filters behave as intended?
If something looks off, return to the gem, adjust the logic, and re-run the pipeline to verify the change.

Inspect expressions

Some transformations rely on expressions defined inside a gem. Use the visual expression builder to:
  • Review comparison logic and conditions
  • Combine conditions with logical operators like AND and OR
  • Work with parameters and dynamic values
After updating an expression, run the pipeline and verify the output in Data Explorer to ensure the expression produces the expected results.

Inspect generated SQL

All pipelines compile to SQL that runs in your warehouse. You can inspect this SQL to verify exactly how transformations are executed. To do this:
  1. Open a gem.
  2. Switch to code view.
  3. Review the generated SQL.
Inspecting SQL is useful when you want to:
  • Confirm how joins, filters, or aggregations are implemented
  • Debug unexpected results at a lower level
  • Validate performance or query structure

Next steps