NVIDIA · yczhang-nv · Sep 15, 2026 · Sep 15, 2026 · Sep 16, 2026
@@ -244,8 +244,8 @@ Use the following resources to learn about NeMo Fabric:
 
 - [Example Notebooks](examples/notebooks/README.md) provide a guided tour of the Python SDK.
 - The [Python SDK guide](docs/sdk/python.mdx) covers typed configuration,
-  planning, diagnostics, requests, multi-turn runtimes, streaming, parallelism,
-  results, and errors.
+  planning, diagnostics, requests, multi-turn runtimes, bounded runtime health
+  checks, streaming, parallelism, results, and errors.
 - The [Experimentation CLI guide](docs/experimentation/cli.mdx) covers presets,
   maintained examples, and editable application scaffolds.
 - The [getting started overview](docs/about-nemo-fabric/overview.mdx) explains

@@ -28,6 +28,10 @@ An adapter descriptor opts into the southbound configuration with
 `config.input=agent_config`. Python adapters using the optional common
 lifecycle host pass `AgentConfig.from_mapping` as the `config_loader`.
 
+The models module also exports `AdapterHealthRequest`, `AdapterHealthResult`,
+`AdapterReadiness`, and `HealthCheck` for optional bounded health hooks used by
+the maintained local lifecycle hosts.
+
 ## Install
 
 Install the package directly when developing a Python adapter:

@@ -34,6 +34,10 @@ NeMo Fabric delivers `AgentConfig` as the southbound configuration. Python
 adapters using the optional common lifecycle host pass
 `AgentConfig.from_mapping` as the `config_loader`.
 
+The models module also exports `AdapterHealthRequest`, `AdapterHealthResult`,
+`AdapterReadiness`, and `HealthCheck` for optional bounded health hooks used by
+the maintained local lifecycle hosts.
+
 ## Install
 
 Install the package directly when developing a Python adapter:

@@ -534,6 +534,79 @@ def _validate(self) -> None:
             raise ContractValidationError("succeeded result must not include an error")
 
 
+class RuntimeReadiness(StrEnum):
+    """Whether an adapter knows its runtime can currently accept work."""
+
+    READY = "ready"
+    NOT_READY = "not_ready"
+    UNKNOWN = "unknown"
+
+
+class HealthCheckStatus(StrEnum):
+    """Outcome of one adapter health check."""
+
+    OK = "ok"
+    FAILED = "failed"
+    UNKNOWN = "unknown"
+    UNSUPPORTED = "unsupported"
+
+
+@dataclass(slots=True, kw_only=True)
+class HealthCheck(ContractModel):
+    """One timestamped adapter or dependency health observation."""
+
+    name: str
+    status: HealthCheckStatus
+    reason_code: str
+    observed_at_millis: int
+    age_millis: int
+    message: str | None = _optional()
+    metadata: dict[str, JsonValue] = _json_dict()
+
+    def _validate(self) -> None:
+        _nonblank(self.name, "name")
+        _nonblank(self.reason_code, "reason_code")
+        _bounded_int(self.observed_at_millis, "observed_at_millis", (1 << 64) - 1)
+        _bounded_int(self.age_millis, "age_millis", (1 << 64) - 1)
+        if self.message is not None:
+            _nonblank(self.message, "message")
+
+
+@dataclass(slots=True, kw_only=True)
+class AdapterHealthRequest(ContractModel):
+    """Budget passed to an optional adapter health hook."""
+
+    runtime_id: str
+    timeout_millis: int
+
+    def _validate(self) -> None:
+        _nonblank(self.runtime_id, "runtime_id")
+        _bounded_int(self.timeout_millis, "timeout_millis", (1 << 64) - 1)
+        if self.timeout_millis == 0:
+            raise ContractValidationError(
+                "must be greater than zero", path=("timeout_millis",)
+            )
+
+
+@dataclass(slots=True, kw_only=True)
+class AdapterReadiness(ContractModel):
+    """Adapter-owned readiness observation."""
+
+    state: RuntimeReadiness
+    reason_code: str
+
+    def _validate(self) -> None:
+        _nonblank(self.reason_code, "reason_code")
+
+
+@dataclass(slots=True, kw_only=True)
+class AdapterHealthResult(ContractModel):
+    """Optional adapter-specific contribution to runtime health."""
+
+    readiness: AdapterReadiness | None = _optional()
+    checks: list[HealthCheck] = _empty_list()
+
+
 class ControlLocation(StrEnum):
     """Where Fabric control code runs relative to the task environment."""
 

@@ -63,6 +63,8 @@ adapter-contract package:
 
 ```typescript
 import type {
+  AdapterHealthRequest,
+  AdapterHealthResult,
   AgentRunRequest,
   AgentRunResult,
 } from "nemo-fabric-adapter-contract";
@@ -74,6 +76,10 @@ Fabric normalizes the result. Token counts originate from JSON Schema `uint64`
 values but are represented as JavaScript `number`; values greater than
 `Number.MAX_SAFE_INTEGER` cannot be represented exactly.
 
+Use `AdapterHealthRequest` and `AdapterHealthResult` only for an optional,
+bounded health method served by a compatible local lifecycle host. Health
+checks must not invoke the agent or mutate runtime state.
+
 ## JSON Schemas
 
 The package bundles byte-identical copies of the canonical schemas. Consumers

@@ -254,6 +254,11 @@
           "description": "Whether an in-flight invocation can be cancelled.",
           "type": "boolean"
         },
+        "health": {
+          "default": false,
+          "description": "Whether the selected runtime exposes bounded health observations.",
+          "type": "boolean"
+        },
         "metadata": {
           "additionalProperties": true,
           "description": "Additional adapter-specific capability metadata.",
@@ -296,6 +301,7 @@
       "$ref": "#/$defs/RuntimeCapabilities",
       "default": {
         "cancellation": false,
+        "health": false,
         "service": false,
         "streaming": false,
         "updates": false

@@ -0,0 +1,25 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "additionalProperties": false,
+  "description": "Request passed to an optional adapter health hook.",
+  "properties": {
+    "runtime_id": {
+      "description": "Runtime being inspected.",
+      "minLength": 1,
+      "pattern": "\\S",
+      "type": "string"
+    },
+    "timeout_millis": {
+      "description": "Remaining health budget in milliseconds.",
+      "format": "uint64",
+      "minimum": 1,
+      "type": "integer"
+    }
+  },
+  "required": [
+    "runtime_id",
+    "timeout_millis"
+  ],
+  "title": "AdapterHealthRequest",
+  "type": "object"
+}
@@ -0,0 +1,151 @@
+{
+  "$defs": {
+    "AdapterReadiness": {
+      "additionalProperties": false,
+      "description": "Adapter-owned readiness observation.",
+      "properties": {
+        "reason_code": {
+          "description": "Stable machine-readable reason.",
+          "minLength": 1,
+          "pattern": "\\S",
+          "type": "string"
+        },
+        "state": {
+          "$ref": "#/$defs/RuntimeReadiness",
+          "description": "Adapter readiness state."
+        }
+      },
+      "required": [
+        "state",
+        "reason_code"
+      ],
+      "type": "object"
+    },
+    "HealthCheck": {
+      "additionalProperties": false,
+      "description": "One timestamped runtime or adapter health observation.",
+      "properties": {
+        "age_millis": {
+          "description": "Age of the evidence when this report was assembled.",
+          "format": "uint64",
+          "minimum": 0,
+          "type": "integer"
+        },
+        "message": {
+          "description": "Optional human-readable diagnostic detail.",
+          "minLength": 1,
+          "pattern": "\\S",
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "metadata": {
+          "additionalProperties": true,
+          "description": "Additional non-sensitive check metadata.",
+          "type": "object"
+        },
+        "name": {
+          "description": "Stable, namespaced check name.",
+          "minLength": 1,
+          "pattern": "\\S",
+          "type": "string"
+        },
+        "observed_at_millis": {
+          "description": "Unix timestamp in milliseconds when the evidence was observed.",
+          "format": "uint64",
+          "minimum": 0,
+          "type": "integer"
+        },
+        "reason_code": {
+          "description": "Stable machine-readable reason.",
+          "minLength": 1,
+          "pattern": "\\S",
+          "type": "string"
+        },
+        "status": {
+          "$ref": "#/$defs/HealthCheckStatus",
+          "description": "Structured check outcome."
+        }
+      },
+      "required": [
+        "name",
+        "status",
+        "reason_code",
+        "observed_at_millis",
+        "age_millis"
+      ],
+      "type": "object"
+    },
+    "HealthCheckStatus": {
+      "description": "Outcome of one runtime health check.",
+      "oneOf": [
+        {
+          "const": "ok",
+          "description": "The check passed.",
+          "type": "string"
+        },
+        {
+          "const": "failed",
+          "description": "The check observed a failure.",
+          "type": "string"
+        },
+        {
+          "const": "unknown",
+          "description": "The check could not establish a result.",
+          "type": "string"
+        },
+        {
+          "const": "unsupported",
+          "description": "The selected adapter does not implement the check.",
+          "type": "string"
+        }
+      ]
+    },
+    "RuntimeReadiness": {
+      "description": "Whether Fabric knows the runtime can currently accept work.",
+      "oneOf": [
+        {
+          "const": "ready",
+          "description": "The runtime can accept work under its current invocation policy.",
+          "type": "string"
+        },
+        {
+          "const": "not_ready",
+          "description": "The runtime is known not to accept work.",
+          "type": "string"
+        },
+        {
+          "const": "unknown",
+          "description": "Fabric lacks enough fresh evidence to decide.",
+          "type": "string"
+        }
+      ]
+    }
+  },
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "additionalProperties": false,
+  "description": "Optional adapter-specific contribution to a runtime health report.",
+  "properties": {
+    "checks": {
+      "description": "Adapter or dependency checks.",
+      "items": {
+        "$ref": "#/$defs/HealthCheck"
+      },
+      "type": "array"
+    },
+    "readiness": {
+      "anyOf": [
+        {
+          "$ref": "#/$defs/AdapterReadiness"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "description": "Adapter-owned readiness override when one is known."
+    }
+  },
+  "title": "AdapterHealthResult",
+  "type": "object"
+}
@@ -42,6 +42,10 @@ try {
     "dist/generated/agent-run-request.js",
     "dist/generated/agent-run-result.d.ts",
     "dist/generated/agent-run-result.js",
+    "dist/generated/adapter-health-request.d.ts",
+    "dist/generated/adapter-health-request.js",
+    "dist/generated/adapter-health-result.d.ts",
+    "dist/generated/adapter-health-result.js",
     "dist/generated/runtime-context.d.ts",
     "dist/generated/runtime-context.js",
     "dist/index.d.ts",
@@ -56,6 +60,8 @@ try {
     "schemas/agent-config.schema.json",
     "schemas/agent-run-request.schema.json",
     "schemas/agent-run-result.schema.json",
+    "schemas/adapter-health-request.schema.json",
+    "schemas/adapter-health-result.schema.json",
     "schemas/runtime-context.schema.json",
   ]);
   const missingFiles = [...expectedFiles].filter(

@@ -53,6 +53,8 @@ const schemaSpecs = [
     output: "agent-run-result.ts",
     generate: generateRunResult,
   },
+  { name: "adapter-health-request", output: "adapter-health-request.ts" },
+  { name: "adapter-health-result", output: "adapter-health-result.ts" },
   { name: "runtime-context", output: "runtime-context.ts" },
 ];
 

@@ -113,6 +113,10 @@ export type RuntimeCapabilities = {
    * Whether an in-flight invocation can be cancelled.
    */
   cancellation?: boolean;
+  /**
+   * Whether the selected runtime exposes bounded health observations.
+   */
+  health?: boolean;
   /**
    * Additional adapter-specific capability metadata.
    */

@@ -0,0 +1,19 @@
+// SPDX-FileCopyrightText: Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+// This file is generated from the canonical adapter-contract JSON Schemas.
+// Do not edit it directly; run `npm run generate` instead.
+
+/**
+ * Request passed to an optional adapter health hook.
+ */
+export interface AdapterHealthRequest {
+  /**
+   * Runtime being inspected.
+   */
+  runtime_id: string;
+  /**
+   * Remaining health budget in milliseconds.
+   */
+  timeout_millis: number;
+}