Control / log · All operations

Annotate a pipeline

A variant of Log and annotate a run

Attach comments, notes, descriptions or groupings to the steps of a pipeline without affecting what it computes.

Status

In arcform

Not built yet

arcform does not do this yet; it would live in how a Protocol runs. Its place on the roadmap

What other tools call it

Meridian's classification; an independent blind rating agreed on 95.7% of 324 rows (variant, version 3).

Alteryx Designer (3)
  • Commentread 2026-09-27

    Annotate the canvas with a note

  • Explorer Boxread 2026-09-27

    Show a web page, directory or file in a box on the canvas as supporting documentation

  • Tool Containerread 2026-09-27

    Group tools on the canvas; a container can be collapsed or disabled

Apache NiFi (1)
  • Labelread 2026-09-27

    Documentation text placed on the canvas beside parts of a dataflow

EasyMorph (2)
  • Generate documentationread 2026-09-27

    Generate HTML documentation of an EasyMorph project

  • To-doread 2026-09-27

    Leave a to-do note in the workflow

RapidMiner Studio (3)
  • Annotateread 2026-09-27

    Add or change key-value annotations on an object

  • Annotations to Dataread 2026-09-27

    Extract an object's annotations into a table

  • Data to Annotationsread 2026-09-27

    Set an object's annotations from the rows of a table

Tableau Prep (2)
  • Descriptionsread 2026-09-27

    Add a description to a flow step or to a change entry

  • Group stepsread 2026-09-27

    Collapse a run of steps into a named group on the canvas

Trifacta (2)
  • Commentread 2026-09-27

    Add a comment to the recipe

  • Comment Transformread 2026-09-27

    Insert a non-functional comment as a recipe step

Background

In Tableau Prep, a description on a flow step, a step group or a cleaning action helps others who later work with the flow understand its steps.[1] In Apache NiFi, Labels are used to provide documentation to parts of a dataflow.[2] In EasyMorph, the To-do action adds a to-do note to a workflow and has no effect on the workflow itself.[3]

When to use it

In Tableau Prep, the Group option gathers sections of a large, complex flow into folders, to make the flow easier to follow, troubleshoot or share with others.[1] In Tableau Prep, grouped steps must be directly connected with a flow line, a step can be in only one group at a time, and groups cannot be nested.[1] In Tableau Prep, a description can be up to 200 characters long.[1]

In Alteryx Designer, the Tool Container groups tools in a workflow, and a container can be collapsed to take up less room on the canvas or disabled to stop the tools inside from running.[4] In Alteryx Designer, the tools inside a disabled Tool Container do not process data until the container is enabled again.[4] A grouping that can be switched off is more than a note, so check that every container in a shared workflow is enabled before trusting what it produced. (Meridian's view)

In EasyMorph, the To-do action has no effect on downstream actions unless columns are added within it, and any added columns are available to the actions downstream.[3] Keep annotations free of side effects, so that removing every note from a pipeline leaves its output unchanged. (Meridian's view)

A comment in source code can explain the author's intent: why the code is as it is.[5] Some contend that describing what code does in a comment is superfluous, and that needing to is a sign the code is too complex.[5] On a pipeline, the step already shows what it does, so a note earns its place by saying why: the business rule, the upstream quirk, the reason a filter exists. (Meridian's view)

The method

In computer programming, a comment is text embedded in source code that a compiler or interpreter ignores.[5] A comment is generally an annotation intended to make the code easier for a programmer to understand.[5] Commenting out lines of code turns program code into comments so that it no longer runs, and doing so systematically can locate the code causing a bug.[5]

Some code comments carry a prefix tag, such as TODO, which describes some work to do.[5] In EasyMorph, a To-do action can name the person who should review it and a due date.[3] In EasyMorph, the To-do list command of the Project metadata action creates a dataset of every To-do action in a project, with its module name, description, assignee and due date.[3]

In Alteryx Designer, the Comment tool adds annotations to the project workspace, for jotting down notes and explaining processes.[6] In Alteryx Designer, the Explorer Box shows a web page, a file directory or a file in a box on the canvas, to display or link to a resource that explains or supports a workflow.[7] In EasyMorph, the Generate project documentation action writes an HTML file describing a project's structure, including its connectors, modules, parameters and the actions applied to each table.[8] In EasyMorph, the Generate project documentation action produces no dataset output and passes on the dataset it receives.[8]

Compared with the alternatives

In RapidMiner, the Annotate operator attaches key/value pairs to a data object, to record information that is not part of the data itself, such as the source of a file.[9] In RapidMiner, the Annotations to Data operator extracts an object's annotations into a data set with one column of annotation names and one of their values.[10]

Sources

  1. [1]Build and Organize your Flow - Tableaudocumentation
  2. [2]Apache NiFi User Guidedocumentation
  3. [3]TO-DO [EasyMorph Help]documentation
  4. [4]Tool Container Tooldocumentation
  5. [5]Comment (computer programming) - Wikipediasecondary source
  6. [6]Comment Tooldocumentation
  7. [7]Explorer Box Tooldocumentation
  8. [8]GENERATE PROJECT DOCUMENTATION [EasyMorph Help]documentation
  9. [9]Annotate - Rapidminer Documentationdocumentation
  10. [10]Annotations to Data - Rapidminer Documentationdocumentation