feat: add target-driven adapter discovery

.agents/skills/contribute-adapter/SKILL.md

@@ -28,8 +28,8 @@ the validation matrix, and `prepare-pr` for review handoff.
 Follow these repository-specific requirements after applying the public skill:
 
 1. Place the adapter under `adapters/<name>/` with `LICENSE -> ../../LICENSE`,
-   `README.md`, `fabric-adapter.json`, language-native package and lock files,
-   a source entry point, and focused tests.
+   `README.md`, `<name>.fabric-adapter.json`, language-native package and lock
+   files, a source entry point, and focused tests.
 2. Give each Python leaf adapter a small base installation, a `harness` extra
    for supported target packages, and a `full` extra for package-installable
    integrations. Add a `relay` extra only when the adapter imports NVIDIA NeMo

README.md

@@ -136,7 +136,8 @@ supported harness, install its package extra and set the corresponding adapter
 ID. Pass harness-specific options through `HarnessConfig.settings` only when
 the selected adapter descriptor declares them in `settings_schema`. Adapters
 that expose selectable executables can accept `FabricConfig.workflow`; the
-descriptor's `workflow_schema` defines and validates that adapter-owned block.
+selected Adapter Target Descriptor defines the workflow entry point and
+validates its settings.
 
 For a guided version of this example, refer to the
 [`01_quickstart.ipynb` notebook](examples/notebooks/01_quickstart.ipynb). The

adapter-contract/typescript/schemas/adapter-descriptor.schema.json

@@ -73,11 +73,6 @@
     "AdapterConfigInput": {
       "description": "Configuration object delivered to an adapter lifecycle host.",
       "oneOf": [
-        {
-          "const": "fabric_config",
-          "description": "Deliver the complete northbound `FabricConfig` for legacy adapters.",
-          "type": "string"
-        },
         {
           "const": "agent_config",
           "description": "Deliver the resolved southbound `AgentConfig` contract.",
@@ -105,7 +100,7 @@
         },
         "input": {
           "$ref": "#/$defs/AdapterConfigInput",
-          "default": "fabric_config",
+          "default": "agent_config",
           "description": "Configuration object delivered to the adapter lifecycle host."
         }
       },
@@ -178,6 +173,16 @@
       },
       "type": "object"
     },
+    "AdapterTargetType": {
+      "description": "Adapter target categories understood by this Adapter Contract version.",
+      "oneOf": [
+        {
+          "const": "workflow",
+          "description": "A separately registered custom-agent or workflow target.",
+          "type": "string"
+        }
+      ]
+    },
     "AdapterTelemetryProviderSupport": {
       "additionalProperties": true,
       "description": "Telemetry capabilities for one adapter-supported provider.",
@@ -278,7 +283,7 @@
     "config": {
       "$ref": "#/$defs/AdapterConfigSupport",
       "default": {
-        "input": "fabric_config"
+        "input": "agent_config"
       },
       "description": "NeMo Fabric config areas this adapter consumes or generates."
     },
@@ -318,12 +323,6 @@
       },
       "type": "object"
     },
-    "harness": {
-      "description": "Stable machine-readable harness identifier implemented by this adapter.",
-      "minLength": 1,
-      "pattern": "\\S",
-      "type": "string"
-    },
     "model_schema": {
       "additionalProperties": true,
       "description": "JSON Schema applied to every normalized `FabricConfig.models` entry.",
@@ -350,6 +349,13 @@
         "null"
       ]
     },
+    "target_types": {
+      "description": "Registered target categories this adapter can execute.",
+      "items": {
+        "$ref": "#/$defs/AdapterTargetType"
+      },
+      "type": "array"
+    },
     "telemetry": {
       "$ref": "#/$defs/AdapterTelemetrySupport",
       "default": {},
@@ -362,20 +368,11 @@
         "object",
         "null"
       ]
-    },
-    "workflow_schema": {
-      "additionalProperties": true,
-      "description": "JSON Schema for adapter-owned `FabricConfig.workflow`.",
-      "type": [
-        "object",
-        "null"
-      ]
     }
   },
   "required": [
     "contract_version",
     "adapter_id",
-    "harness",
     "adapter_kind"
   ],
   "title": "AdapterDescriptor",

adapter-contract/typescript/schemas/adapter-target-descriptor.schema.json

@@ -0,0 +1,98 @@
+{
+  "$defs": {
+    "WorkflowEntrypointConfig": {
+      "additionalProperties": true,
+      "description": "Adapter-owned workflow entry point supplied by an Adapter Target Descriptor.",
+      "properties": {
+        "kind": {
+          "description": "Adapter-defined entry-point resolution semantics.",
+          "minLength": 1,
+          "pattern": "\\S",
+          "type": "string"
+        },
+        "ref": {
+          "description": "Adapter-defined workflow reference.",
+          "minLength": 1,
+          "pattern": "\\S",
+          "type": "string"
+        }
+      },
+      "required": [
+        "kind",
+        "ref"
+      ],
+      "type": "object"
+    },
+    "WorkflowTargetSpec": {
+      "additionalProperties": true,
+      "description": "Workflow-specific Adapter Target Descriptor fields.",
+      "properties": {
+        "entrypoint": {
+          "$ref": "#/$defs/WorkflowEntrypointConfig",
+          "description": "Entry point projected southbound to the adapter."
+        },
+        "settings_schema": {
+          "additionalProperties": true,
+          "description": "JSON Schema for `FabricConfig.workflow.settings`.",
+          "type": [
+            "object",
+            "null"
+          ]
+        }
+      },
+      "required": [
+        "entrypoint"
+      ],
+      "type": "object"
+    }
+  },
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "description": "Independently registered target implemented by an adapter.",
+  "oneOf": [
+    {
+      "description": "Registered workflow target.",
+      "properties": {
+        "spec": {
+          "$ref": "#/$defs/WorkflowTargetSpec"
+        },
+        "type": {
+          "const": "workflow",
+          "type": "string"
+        }
+      },
+      "required": [
+        "type",
+        "spec"
+      ],
+      "type": "object"
+    }
+  ],
+  "properties": {
+    "adapter_id": {
+      "description": "Adapter implementation selected by this target.",
+      "minLength": 1,
+      "pattern": "\\S",
+      "type": "string"
+    },
+    "contract_version": {
+      "const": "fabric.adapter/v1alpha2",
+      "description": "Adapter Contract version shared with Adapter Descriptor.",
+      "minLength": 1,
+      "type": "string"
+    },
+    "id": {
+      "description": "Unique registered target id.",
+      "minLength": 1,
+      "pattern": "\\S",
+      "type": "string"
+    }
+  },
+  "required": [
+    "contract_version",
+    "id",
+    "adapter_id"
+  ],
+  "title": "AdapterTargetDescriptor",
+  "type": "object",
+  "unevaluatedProperties": true
+}

adapter-contract/typescript/scripts/check-package.mjs

@@ -34,6 +34,8 @@ try {
     "README.md",
     "dist/generated/adapter-descriptor.d.ts",
     "dist/generated/adapter-descriptor.js",
+    "dist/generated/adapter-target-descriptor.d.ts",
+    "dist/generated/adapter-target-descriptor.js",
     "dist/generated/agent-config.d.ts",
     "dist/generated/agent-config.js",
     "dist/generated/agent-run-request.d.ts",
@@ -50,6 +52,7 @@ try {
     "dist/version.js",
     "package.json",
     "schemas/adapter-descriptor.schema.json",
+    "schemas/adapter-target-descriptor.schema.json",
     "schemas/agent-config.schema.json",
     "schemas/agent-run-request.schema.json",
     "schemas/agent-run-result.schema.json",
@@ -120,20 +123,28 @@ try {
     `import { ADAPTER_CONTRACT_VERSION } from "nemo-fabric-adapter-contract";
 import agentConfigSchema from "nemo-fabric-adapter-contract/schemas/agent-config" with { type: "json" };
 import type { AdapterDescriptor } from "nemo-fabric-adapter-contract";
+import type { AdapterTargetDescriptor } from "nemo-fabric-adapter-contract";
 import type { AgentRunResult } from "nemo-fabric-adapter-contract";
 
 const descriptor: AdapterDescriptor = {
   adapter_id: "example",
   adapter_kind: "process",
   contract_version: ADAPTER_CONTRACT_VERSION,
-  harness: "example",
+};
+const target: AdapterTargetDescriptor = {
+  adapter_id: "example",
+  contract_version: ADAPTER_CONTRACT_VERSION,
+  id: "example.workflow",
+  spec: { entrypoint: { kind: "factory", ref: "example.agent" } },
+  type: "workflow",
 };
 const result: AgentRunResult = {
   output: ["ok", null],
   status: "succeeded",
 };
 if (
   descriptor.contract_version !== ADAPTER_CONTRACT_VERSION ||
+  target.adapter_id !== descriptor.adapter_id ||
   result.status !== "succeeded" ||
   agentConfigSchema.title !== "AgentConfig"
 ) {

adapter-contract/typescript/scripts/generate.mjs

@@ -37,6 +37,11 @@ const schemaSpecs = [
     output: "adapter-descriptor.ts",
     project: projectAdapterDescriptor,
   },
+  {
+    name: "adapter-target-descriptor",
+    output: "adapter-target-descriptor.ts",
+    project: projectAdapterTargetDescriptor,
+  },
   { name: "agent-config", output: "agent-config.ts" },
   {
     name: "agent-run-request",
@@ -233,6 +238,21 @@ function projectAdapterDescriptor(original) {
   return schema;
 }
 
+function projectAdapterTargetDescriptor(original) {
+  const schema = deepClone(original);
+  const contractVersion = requireString(
+    schema.properties?.contract_version?.const,
+    "adapter-target-descriptor contract_version.const",
+  );
+  schema.properties.contract_version.tsType = JSON.stringify(contractVersion);
+  // schemars emits `unevaluatedProperties` for the flattened target enum.
+  // Project the same open extension surface in the form understood by the
+  // TypeScript generator and its JsonObject guard.
+  delete schema.unevaluatedProperties;
+  schema.additionalProperties = true;
+  return schema;
+}
+
 function projectRunRequest(original) {
   const schema = deepClone(original);
   const input = schema.properties?.input;
@@ -399,11 +419,15 @@ function replaceGeneratedPropertyType(output, property, projectedType) {
 function projectOpenInterfaces(output) {
   const openInterface =
     /export interface ([A-Za-z][A-Za-z0-9]*) \{\n((?:(?!^export (?:interface|type) ).)*?)  \[k: string\]: unknown;\n\}/gms;
-  const projected = output.replace(
+  const projectedInterfaces = output.replace(
     openInterface,
     (_match, name, fields) =>
       `export type ${name} = {\n${fields}} & JsonObject;`,
   );
+  const projected = projectedInterfaces.replace(
+    /  \[k: string\]: unknown;\n\}/g,
+    "} & JsonObject",
+  );
   if (projected.includes("[k: string]: unknown;")) {
     throw new Error(
       "Generated output contains an open object that was not projected to JsonObject",

adapter-contract/typescript/src/generated/adapter-descriptor.ts

@@ -49,6 +49,10 @@ export type AdapterConfigField =
   | "mcp.auth.service_account"
   | "mcp.tool_filters"
   | "skills";
+/**
+ * Adapter target categories understood by this Adapter Contract version.
+ */
+export type AdapterTargetType = "workflow";
 
 /**
  * Language-neutral adapter descriptor for a harness integration.
@@ -72,10 +76,6 @@ export type AdapterDescriptor = {
    * JSON Schemas for adapter-owned `extensions` at southbound block types.
    */
   extension_schemas?: Partial<Record<AdapterExtensionPoint, JsonObject>>;
-  /**
-   * Stable machine-readable harness identifier implemented by this adapter.
-   */
-  harness: string;
   /**
    * JSON Schema applied to every normalized `FabricConfig.models` entry.
    */
@@ -89,15 +89,15 @@ export type AdapterDescriptor = {
    * JSON Schema for adapter-owned `harness.settings`.
    */
   settings_schema?: JsonObject | null;
+  /**
+   * Registered target categories this adapter can execute.
+   */
+  target_types?: AdapterTargetType[];
   telemetry?: AdapterTelemetrySupport;
   /**
    * JSON Schema applied to every normalized `FabricConfig.tools.definitions` entry.
    */
   tool_definition_schema?: JsonObject | null;
-  /**
-   * JSON Schema for adapter-owned `FabricConfig.workflow`.
-   */
-  workflow_schema?: JsonObject | null;
 } & JsonObject;
 /**
  * Runtime lifecycle operations supported by this adapter.
@@ -139,7 +139,7 @@ export type AdapterConfigSupport = {
   /**
    * Configuration object delivered to the adapter lifecycle host.
    */
-  input?: "fabric_config" | "agent_config";
+  input?: "agent_config";
 } & JsonObject;
 /**
  * Runtime requirements.