Field notes: Connectors, muscles, and governed workflows
HUMΛN Team··7 min·Engineers
Why the vocabulary matters
Security reviews fail when everything is called an “integration.” Connectors, muscles, and workflows answer different questions:
| Primitive | Question it answers |
|---|---|
| Connector | How do we reach Slack / Postgres / email with org-scoped credentials? |
| Muscle | What governed code runs inside the platform envelope? |
| Workflow | How do steps compose under HumanOS policy and observability? |
Collapsing them breaks both architecture diagrams and least-privilege reviews.
How bundles compose them
A humanos.bundle.v1 manifest lists members with explicit kind: connector, muscle, workflow, agent, extension. Install order defaults to workflows → agents → connectors (tunable via install_order), implemented in sortMembers in install-bundle.ts.
- Connectors go through
installConnector+ marketplace installation rows. - Workflows / muscles register config layers and CP extension hooks where manifests declare them.
Mental model
Connector (external system) → workflow step → muscle or agent → ActionReceipt / DAG node
Implementation evidence
@human/connector-sdkvs muscle / agent runtimes (separate packages, separate review).apps/api/src/services/install-bundle.ts— member kind dispatch.- kb/163 workflow recipe — 14 configuration primitives; workflows stay HumanOS-governed.
If your diagram has only one box labeled “automation,” redraw it before you audit it.