Workflow Input Contract

When Axiom starts a workflow for a project, it injects a fixed, canonical set of inputs into the workflow's initial context. Workflow definitions may depend only on these inputs. This keeps a definition runnable by construction — there is no way to supply arbitrary inputs from the "Run Workflow" dialog.

Canonical inputs

name	type	presence	may be required?
projectId	number	always	yes
ref	string	always	yes
event	object	only when the run was started by a subscription's create-workflow routing rule	no — must be optional
projectName	string	never populated automatically (see below)	no — must be optional
repository	string	never populated automatically (see below)	no — must be optional

Only projectId and ref are guaranteed to be present in every workflow run, and only these two may be declared required on the Start node.

event is populated with the triggering event's envelope (type, source, connectionId, ref, timestamp, actor, payload) only when the workflow instance was started by a subscription's create-workflow routing rule. Manually triggered runs (from the project detail page or the "Run Workflow" dialog) do not populate event.

projectName and repository are accepted as valid Start-node input names — so a definition may declare them without failing publish validation — but Axiom does not currently inject values for them into any workflow's initial context. Declare them only if you plan to resolve them another way (e.g. via an early action node that fetches project details), and always as optional inputs, since a required declaration for either name is rejected at publish time.

Rules enforced at publish

A workflow definition's Start node declares its inputs under config.inputs (a list of { name, type, required, description }). At publish time Axiom rejects a definition when:

1. The Start node declares an input whose name is not one of the canonical inputs (projectId, ref, event, projectName, repository).
2. The Start node marks any input other than projectId or ref as required.

New definitions are scaffolded with three inputs already declared: projectId (required, number), ref (required, string), and event (optional, object, described as "present when created by subscription routing").

Run-time behavior

As defense-in-depth for legacy or hand-edited definitions, a trigger whose context does not satisfy a required Start-node input fails with HTTP 400 and a message naming the missing input, which the UI surfaces in the Run Workflow dialog.