Plugin Capability

Plugin Capability Protocol

Defines the standard way plugins declare their capabilities, implementations, and conformance levels to ensure interoperability across vendors.

Based on the Protocol-Oriented Architecture pattern similar to:

Kubernetes CRDs (Custom Resource Definitions)
OSGi Service Registry
Eclipse Extension Points

Source: packages/spec/src/kernel/plugin-capability.zod.ts

TypeScript Usage

import { CapabilityConformanceLevelSchema, ExtensionPointSchema, PluginCapabilitySchema, PluginCapabilityManifestSchema, PluginDependencySchema, PluginInterfaceSchema, ProtocolFeatureSchema, ProtocolReferenceSchema, ProtocolVersionSchema } from '@objectstack/spec/kernel';
import type { CapabilityConformanceLevel, ExtensionPoint, PluginCapability, PluginCapabilityManifest, PluginDependency, PluginInterface, ProtocolFeature, ProtocolReference, ProtocolVersion } from '@objectstack/spec/kernel';

// Validate data
const result = CapabilityConformanceLevelSchema.parse(data);

CapabilityConformanceLevel

Level of protocol conformance

Allowed Values

full
partial
experimental
deprecated

ExtensionPoint

Properties

Property	Type	Required	Description
id	`string`	✅	Unique extension point identifier
name	`string`	✅
description	`string`	optional
type	`Enum<'action' \| 'hook' \| 'widget' \| 'provider' \| 'transformer' \| 'validator' \| 'decorator'>`	✅
contract	`{ input?: string; output?: string; signature?: string }`	optional
cardinality	`Enum<'single' \| 'multiple'>`	optional (default: `"multiple"`)	Whether multiple extensions can register to this point

Nested Shape: `ExtensionPoint.contract`

Property	Type	Required	Description
input	`string`	optional	Input type/schema
output	`string`	optional	Output type/schema
signature	`string`	optional	Function signature if applicable

PluginCapability

Properties

Property	Type	Required	Description
protocol	`{ id: string; label: string; version: object; specification?: string; … }`	✅
conformance	`Enum<'full' \| 'partial' \| 'experimental' \| 'deprecated'>`	optional (default: `"full"`)	Level of protocol conformance
implementedFeatures	`string[]`	optional	List of implemented feature names
features	`{ name: string; enabled: boolean; description?: string; sinceVersion?: string; … }[]`	optional
metadata	`Record<string, any>`	optional
certified	`boolean`	optional (default: `false`)	Has passed official conformance tests
certificationDate	`string`	optional

Nested Shape: `PluginCapability.protocol`

Property	Type	Required	Description
id	`string`	✅	Unique protocol identifier (e.g., com.objectstack.protocol.storage.v1)
label	`string`	✅
version	`{ major: integer; minor: integer; patch: integer }`	✅	Semantic version of the protocol
specification	`string`	optional	URL or path to protocol specification
description	`string`	optional

Nested Shape: `PluginCapability.features[number]`

Property	Type	Required	Description
name	`string`	✅	Feature identifier within the protocol
enabled	`boolean`	optional (default: `true`)
description	`string`	optional
sinceVersion	`string`	optional	Version when this feature was added
deprecatedSince	`string`	optional	Version when deprecated

PluginCapabilityManifest

Properties

Property	Type	Required	Description
implements	`{ protocol: object; conformance: Enum<'full' \| 'partial' \| 'experimental' \| 'deprecated'>; implementedFeatures?: string[]; features?: object[]; … }[]`	optional	List of protocols this plugin conforms to
provides	`{ id: string; name: string; description?: string; version: object; … }[]`	optional	Services/APIs this plugin offers to others
requires	`{ pluginId: string; version: string; optional: boolean; reason?: string; … }[]`	optional	Required plugins and their capabilities
extensionPoints	`{ id: string; name: string; description?: string; type: Enum<'action' \| 'hook' \| 'widget' \| 'provider' \| 'transformer' \| 'validator' \| 'decorator'>; … }[]`	optional	Points where other plugins can extend this plugin
extensions	`{ targetPluginId: string; extensionPointId: string; implementation: string; priority: integer }[]`	optional	Extensions contributed to other plugins

Nested Shape: `PluginCapabilityManifest.implements[number]`

Property	Type	Required	Description
protocol	`{ id: string; label: string; version: object; specification?: string; … }`	✅
conformance	`Enum<'full' \| 'partial' \| 'experimental' \| 'deprecated'>`	optional (default: `"full"`)	Level of protocol conformance
implementedFeatures	`string[]`	optional	List of implemented feature names
features	`{ name: string; enabled: boolean; description?: string; sinceVersion?: string; … }[]`	optional
metadata	`Record<string, any>`	optional
certified	`boolean`	optional (default: `false`)	Has passed official conformance tests
certificationDate	`string`	optional

Nested Shape: `PluginCapabilityManifest.provides[number]`

Property	Type	Required	Description
id	`string`	✅	Unique interface identifier
name	`string`	✅
description	`string`	optional
version	`{ major: integer; minor: integer; patch: integer }`	✅	Semantic version of the protocol
methods	`{ name: string; description?: string; parameters?: object[]; returnType?: string; … }[]`	✅
events	`{ name: string; description?: string; payload?: string }[]`	optional
stability	`Enum<'stable' \| 'beta' \| 'alpha' \| 'experimental'>`	optional (default: `"stable"`)

Nested Shape: `PluginCapabilityManifest.requires[number]`

Property	Type	Required	Description
pluginId	`string`	✅	Required plugin identifier
version	`string`	✅	Semantic version constraint
optional	`boolean`	optional (default: `false`)
reason	`string`	optional
requiredCapabilities	`string[]`	optional	Protocol IDs the dependency must support

Nested Shape: `PluginCapabilityManifest.extensionPoints[number]`

Property	Type	Required	Description
id	`string`	✅	Unique extension point identifier
name	`string`	✅
description	`string`	optional
type	`Enum<'action' \| 'hook' \| 'widget' \| 'provider' \| 'transformer' \| 'validator' \| 'decorator'>`	✅
contract	`{ input?: string; output?: string; signature?: string }`	optional
cardinality	`Enum<'single' \| 'multiple'>`	optional (default: `"multiple"`)	Whether multiple extensions can register to this point

Nested Shape: `PluginCapabilityManifest.extensions[number]`

Property	Type	Required	Description
targetPluginId	`string`	✅	Plugin ID being extended
extensionPointId	`string`	✅	Extension point identifier
implementation	`string`	✅	Path to implementation module
priority	`integer`	optional (default: `100`)	Registration priority (lower = higher priority)

PluginDependency

Properties

Property	Type	Required	Description
pluginId	`string`	✅	Required plugin identifier
version	`string`	✅	Semantic version constraint
optional	`boolean`	optional (default: `false`)
reason	`string`	optional
requiredCapabilities	`string[]`	optional	Protocol IDs the dependency must support

PluginInterface

Properties

Property	Type	Required	Description
id	`string`	✅	Unique interface identifier
name	`string`	✅
description	`string`	optional
version	`{ major: integer; minor: integer; patch: integer }`	✅	Semantic version of the protocol
methods	`{ name: string; description?: string; parameters?: object[]; returnType?: string; … }[]`	✅
events	`{ name: string; description?: string; payload?: string }[]`	optional
stability	`Enum<'stable' \| 'beta' \| 'alpha' \| 'experimental'>`	optional (default: `"stable"`)

Nested Shape: `PluginInterface.methods[number]`

Property	Type	Required	Description
name	`string`	✅	Method name
description	`string`	optional
parameters	`{ name: string; type: string; required: boolean; description?: string }[]`	optional
returnType	`string`	optional	Return value type
async	`boolean`	optional (default: `false`)	Whether method returns a Promise

Nested Shape: `PluginInterface.events[number]`

Property	Type	Required	Description
name	`string`	✅	Event name
description	`string`	optional
payload	`string`	optional	Event payload type

ProtocolFeature

Properties

Property	Type	Required	Description
name	`string`	✅	Feature identifier within the protocol
enabled	`boolean`	optional (default: `true`)
description	`string`	optional
sinceVersion	`string`	optional	Version when this feature was added
deprecatedSince	`string`	optional	Version when deprecated

ProtocolReference

Properties

Property	Type	Required	Description
id	`string`	✅	Unique protocol identifier (e.g., com.objectstack.protocol.storage.v1)
label	`string`	✅
version	`{ major: integer; minor: integer; patch: integer }`	✅	Semantic version of the protocol
specification	`string`	optional	URL or path to protocol specification
description	`string`	optional

ProtocolVersion

Semantic version of the protocol

Properties

Property	Type	Required
major	`integer`	✅
minor	`integer`	✅
patch	`integer`	✅

Plugin Capability

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