---
id: CMP-1
family: RT-CMP
level: core
profiles: [runtime]
posture: normative-target
added: "1.0"
changed: "1.0"
source: https://flowdrop.io/spec/rules/rt-cmp/cmp-1
specification: FlowDrop Workflow Specification 1.0-draft
licence: CC BY 4.0
---

# CMP-1 — Compilation is one operation with one failure surface

*RT-CMP (Part II) · level: core · profiles: runtime · added in 1.0*

Compiling a stored workflow produces the executable plan in a fixed stage order. A caller that hands over an invalid workflow sees one kind of failure, whichever stage detected it.

## The rule

> **Normative.** This is the rule.
>
> 1. Compiling a workflow produces a dependency graph over all of its edges, an execution graph of the nodes that will run, and, for each of those nodes, the mapping the runtime executes it through.
>
> 2. The stages run in this order: structure preconditions, dependency graph, cycle detection, tool wiring, execution graph, node mappings.
>
> 3. A failure in any stage is reported to the caller as a single compilation failure, whose message carries the detecting stage's message prefixed exactly once and whose underlying cause remains reachable.


## What it means

Compilation runs six stages in a fixed order: structure preconditions,
dependency graph, cycle detection, tool wiring, execution graph, node
mappings. Wherever in that order something goes wrong, the caller sees one
failure shape, not six, and its message names which stage caught it.

The detail a fixed order does not make obvious on its own: the prefix is
never doubled. A structure precondition (CMP-3) is itself already reported
as a compilation failure — the cheapest stage runs first and reports in the
same shape everything else does — so wrapping its message a second time
could easily stack the prefix twice. It does not: compilation reports the
outer message once, and the failure that was actually detected stays
reachable underneath it rather than being discarded.

## Example

A workflow whose only node has no declared type — a structure precondition,
caught at the first stage:

```json title="A node with no declared type" verdict="given"
{ "id": "wrap_probe", "nodes": [{ "id": "node1" }] }
```

```json title="What compilation reports" verdict="reported"
"Workflow compilation failed: Node node1 must have a type"
```

The failure reachable underneath that message is `Node node1 must have a
type` — the detecting stage's own message, present once, not twice.

## Related rules

- Names: CMP-3, CMP-5, CMP-6, CMP-9, CMP-11
- Referenced by: CMP-3, CMP-5, CMP-11

---

Rule identifiers are permanent and are never renumbered. This specification carries
no implementation status: each implementation publishes its own standing against
these rules. Licensed CC BY 4.0.