microsoft/semantic-kernel · error · InvalidOperationException

No OpenAPI runtimes found in the manifest.

Error message

No OpenAPI runtimes found in the manifest.

What it means

Thrown when a Copilot Agent Plugin manifest parses successfully but its runtimes collection contains no entry whose Type equals RuntimeType.OpenApi. SK only knows how to execute OpenApi runtimes, so a manifest advertising only other runtime types (or none) cannot produce any kernel functions.

Source

Thrown at dotnet/src/Functions/Functions.OpenApi.Extensions/Extensions/CopilotAgentPluginKernelExtensions.cs:96

        using var CopilotAgentFileJsonContents = DocumentLoader.LoadDocumentFromFilePathAsStream(filePath,
            logger);

        var results = await PluginManifestDocument.LoadAsync(CopilotAgentFileJsonContents, new ReaderOptions
        {
            ValidationRules = [] // Disable validation rules
        }).ConfigureAwait(false);

        if (!results.IsValid)
        {
            var messages = results.Problems.Select(static p => p.Message).Aggregate(static (a, b) => $"{a}, {b}");
            throw new InvalidOperationException($"Error loading the manifest: {messages}");
        }

        var document = results.Document;
        var openAPIRuntimes = document?.Runtimes?.Where(runtime => runtime.Type == RuntimeType.OpenApi).ToList();
        if (openAPIRuntimes is null || openAPIRuntimes.Count == 0)
        {
            throw new InvalidOperationException("No OpenAPI runtimes found in the manifest.");
        }

        var functions = new List<KernelFunction>();
        var documentWalker = new OpenApiWalker(new OperationIdNormalizationOpenApiVisitor());
        foreach (var runtime in openAPIRuntimes)
        {
            var manifestFunctions = document?.Functions?.Where(f => runtime.RunForFunctions.Contains(f.Name)).ToList();
            if (manifestFunctions is null || manifestFunctions.Count == 0)
            {
                logger.LogWarning("No functions found in the runtime object.");
                continue;
            }

            var openApiRuntime = runtime as OpenApiRuntime;
            var apiDescriptionUrl = openApiRuntime?.Spec?.Url ?? string.Empty;
            if (apiDescriptionUrl.Length == 0)
            {
                logger.LogWarning("No API description URL found in the runtime object.");

View on GitHub (pinned to c028a0c7dc)

Solutions

1. Open the manifest and confirm the runtimes array contains at least one object with type set to OpenApi.
2. Verify each runtime has a Spec.Url pointing to a reachable OpenAPI document (local relative path or absolute URL).
3. If the manifest was generated, regenerate it with a current version of the Teams Toolkit / declarative-agent tooling that emits OpenApi runtimes.
4. If you only have an OpenAPI spec and no plugin manifest, use kernel.ImportPluginFromOpenApiAsync instead of the Copilot Agent Plugin loader.

Example fix

// before - manifest has no runtimes or wrong type
"runtimes": [ { "type": "REST", "spec": { "url": "openapi.json" } } ]

// after
"runtimes": [ { "type": "OpenApi", "spec": { "url": "openapi.json" }, "runForFunctions": [ "getEmails" ] } ]

var manifest = JsonNode.Parse(File.ReadAllText(filePath));
var openApiRuntimes = manifest?["runtimes"]?.AsArray()
    .Where(r => r?["type"]?.GetValue<string>() == "OpenApi").ToList();
if (openApiRuntimes is null || openApiRuntimes.Count == 0)
    throw new InvalidOperationException("Manifest has no OpenApi runtimes.");

When it happens

Trigger: A manifest whose runtimes array is empty, null, or contains only non-OpenApi runtime types (e.g. a Script or a type that is not 'OpenApi'). Also when the 'type' field is misspelled or uses a different casing/label than the schema expects.

Common situations: Manifest generated by a tool that omitted the runtimes block; manually authored manifest where the runtime type string does not resolve to OpenApi; mismatch between the manifest schema version SK expects and the one used to author it.

Related errors

• CopilotAgent file not found: {filePath}
• Error loading the manifest: {messages}
• AZURE_OPENAI_ENDPOINT is not set.
• Agent Failure - Run terminated: {run.Status} [{run.Id}]: {ru
• Agent Failure - Run not created for thread: ${threadId}

AI-assisted analysis of microsoft/semantic-kernel@c028a0c7dc (2026-08-13). Data as JSON: /api/errors/06068b75ce40b2b7. Report an issue: GitHub.