ws-graph-engineeringlisted

# Graph Engineering The ws plugin treats its ws-matt vendored skills plus this one as a **graph**: skills are nodes, their cross-references are edges, and the conversation plus the scratch directory form the shared state. The model is the runtime — it walks the edges. This skill is the contract every node follows. ## The node contract A node (a skill invocation, or a worker agent run) does exactly one thing: > **Read shared state → do its work → return a state delta.** - Shared state = the conversation so far, files in the repo, and artifacts under the scratch directory. - A state delta = new artifacts written, decisions recorded, a structured return. - A node **never mutates** state another node owns — it only adds. If a node needs an upstream artifact changed, it routes back to the node that owns it (a goto); it does not edit the artifact in place. ## Edge types | Edge | Form | Meaning | |---|---|---| | Deterministic | `then → ws-<node>` | Always taken next. | | Conditional | `when <condition> → ws-<node>` | Taken only when the condition holds. | | Dynamic fan-out | `fan-out: for each <item> spawn <agent>` | N workers decided at runtime from state (Send-style) — one worker per item, all in parallel. | Every vendored skill declares its edges in a trailing `## Graph node` section. Follow the declared edges; do not invent edges mid-run. ## Fan-in: declared merge rules When parallel workers return, their deltas merge into shared state by **declared reducers** —