Flow Studio
Node Capabilities Overview
What node capabilities are, why they exist, the 12 capability types, and how capability metadata drives node discovery, palette grouping, and security policies.
What Are Node Capabilities?
A node capability declares what external system category a node integrates with. It is a classification tag — not a runtime contract — that tells the platform:
- Which section of the node palette this node belongs to
- What security policy controls its usage (NodeCapabilityPolicy)
- What icon to display on the node tile in the designer
- What services it needs registered in DI
Capabilities are declared with a simple attribute on the executor class. The engine discovers them automatically at startup — no manual registration required.
The 12 Capability Types
| # | Capability | Domain | Example Nodes |
|---|---|---|---|
| 1 | Webhook | HTTP event triggers & outbound calls | WebhookTriggerNode, WebhookCallNode |
| 2 | BusinessService | Internal platform service APIs | BusinessServiceCallNode |
| 3 | Form | Atlas Forms HIL integration | UserFormNode |
| 4 | Widget | UI widget HIL steps | WidgetNode |
| 5 | Messaging | Slack, email, SMS, push | SendSlackNode, SendEmailNode |
| 6 | Identity | User lookup, roles, permissions | UserLookupNode, PermissionCheckNode |
| 7 | Entity | Business entity CRUD | EntityReadNode, EntityQueryNode |
| 8 | Datasource | SQL, REST, DataOcean queries | SqlQueryNode, RestDatasourceNode |
| 9 | Rule | Rule engine evaluation | RuleEvalNode |
| 10 | Process | Workflow lifecycle control | StartWorkflowNode, CancelWorkflowNode |
| 11 | DIDComm | Decentralized identity messaging | DIDCommSendNode, VCVerifyNode |
| 12 | MCP | AI tool server calls | MCPToolCallNode |
Why Capabilities Matter
- Discoverability: The palette groups nodes by capability — designers find related nodes quickly
- Security: A
NodeCapabilityPolicycan restrict which tenants or roles can use nodes of a given capability type - Observability: Execution logs tag node runs with capability type for filtering
- Extensibility: Adding a new capability type automatically flows through palette, security, and observability without extra code
Gateway to deep dives: Each capability type has its own dedicated guide (Guide36 through Guide47). This overview guide is the entry point — use the Capability Type Map page to navigate to the specific guide for each capability.