Flows
Testing a real API journey almost never means firing one request. It means: log in, take the token from the response, use it on the next call, check that call returned what you expected, maybe loop over a list, maybe branch on a status code. Doing that by hand in Composer means re-typing headers and copy-pasting values between tabs, every single time you want to re-run it.
Flows turn that journey into a diagram you build once and run forever. Drag requests onto a canvas, wire them together, tell Probe which values to carry from one response into the next request, and add assertions to check what came back. Hit Run and watch each node light up as it executes. Save the flow, share it with a teammate as a file, or run it headlessly in CI.
What a flow is
Section titled “What a flow is”A flow is a small graph:
- Nodes are steps — an HTTP request, a branch, a loop, a pause, a call into another flow, or a script.
- Edges are the order nodes run in. Drag from one node's out-port to another node's in-port to connect them.
- Variables carry data along the edges. Name an extraction on a request node (e.g. pull
tokenout of the login response body), and any downstream node can reference it as{{login.outputs.token}}— in a URL, a header, or a body field.
That's the whole model. There's no separate "test script" language to learn for the common case — extractions and assertions are just fields you fill in on a node, and they show up right there on the canvas.
Where it lives
Section titled “Where it lives”Flows share the request-building side of Probe with Composer. Click the API Client icon at the top of the sidebar to switch into Composer view, then look for the FLOWS section in the sidebar, below your collections. Click + to create a new flow, or click an existing one to open (or refocus) its tab.
Because a flow's request nodes reference real requests from your Composer collections, a request node sends that request's headers, Params rows and body, plus any cookies set earlier in the same run (a response's Set-Cookie); the Cookies tab of the saved request is not sent, and the headless CLI sends no cookies. It does not apply the request's or collection's auth, the collection's default headers, the GraphQL envelope or form-data and binary bodies, so set Authorization in the node's headers.
Layout
Section titled “Layout”
Requests get dragged onto the canvas straight from the Composer collection tree in the sidebar. Selecting a node opens its inspector (config: extractions, assertions, condition expression, loop source, etc.) — the inspector isn't drawn above: it docks on the right of the canvas while any node other than Start is selected.
The seven node types
Section titled “The seven node types”Every flow is built from seven kinds of node — Start, Request, Condition, Loop, Delay, Sub-flow, and Script. See Node Types for what each one does, its ports, and its settings.