Testing & Debugging | Gail Documentation

Before you rely on a workflow, you want to see it work. Two features help: a step-through debugger that lets you walk a run node by node, and run history that shows what happened during any run. Together they turn “I think this works” into “I watched it work.”

Stepping through a run

The debugger starts a run and pauses it before the first step. From there you can advance one step at a time, or let it run to the end. Each time it pauses, you can see what is about to happen and what just happened.

Start a session

Pick a workflow and start a debug session. The run pauses at the very beginning, before anything has happened.

Step forward

Advance by one step. That step runs, then the session pauses again before the next one, so you can inspect the result.

Inspect the pause

At each pause you can see the details below: the input the next step will use, the output of the step that just ran, and the current values in the run.

Run to the end

When you have seen enough, let the session run the rest of the way to a finish, or stop it to end the session early.

What you can see at each pause

At a pause	What it shows
Next step’s input	The exact values the upcoming step will run with, after any expressions have been worked out.
Previous step’s output	What the step that just ran produced.
Branch decision	When a Conditional has run, which path it chose and why.
Current values	All the values available at this point, grouped as node, config, secret, and system. Secret values are shown masked as `*******`.

Debugging runs a workflow for real. Steps that send messages, place calls, or write to other systems will actually do those things while you step through. Use test data, or a workflow set up for testing, if you do not want real effects.

A paused session does not stay open forever. If you leave it idle for a while (about 15 minutes), it ends on its own. Taking any action keeps it going.

Following a run’s progress

Every run, whether you started it by hand or it was triggered, builds up a history as it goes: a timeline of events you can follow in real time. It records when the run started, when each step started and finished, which path a Conditional took, and when the run completed or was cancelled.

This is how you check on a run without stepping through it. You can watch a live run move along, or open a finished run to see everything that happened and in what order. If a step failed, the history shows where.

If a step produces a very large output, its entry in the history is shortened so the timeline stays quick to load. This only affects what the history displays; the full value is still passed on to the next step as normal.

Timeouts & Retries

Understand how a slow or failing step is handled during a run.

Variables & Data Flow

Make sense of the values you see at each pause.