.NET: Add feature-usage bitmask

[Peter Ibekwe (peibekwe)]

Motivation & Context

Agent Framework currently identifies .NET SDK traffic but does not report which framework capabilities are actually exercised together. This implements ADR-0033’s transparent, privacy-scoped feature-usage signal for .NET.

Description & Review Guide

• Adds a process-wide, monotonic 128-bit feature mask with package-local feature indexes.
• Marks features at their first meaningful activation.
• Emits  (feat=v1.)  at request time through approved Foundry and Azure OpenAI wrappers.
• Restricts emission to reviewed HTTPS origins and removes stale tokens from ineligible requests.
• Adds registry validation, activation/emission tests, and the AGENT_FRAMEWORK_FEATURE_MASK_DISABLED opt-out.

Fixes #7422

Contribution Checklist

• The code builds clean without any errors or warnings
• All unit tests pass, and I have added new tests where possible
• The PR follows the Contribution Guidelines
• This PR is linked to an issue and there is no other open PR for this issue (see Related Issue above).
• This is not a breaking change. If it is a breaking change, add the breaking change label (or add "[BREAKING]" to the title prefix, before or after any language prefix) — a workflow keeps the label and title prefix in sync automatically.

[Copilot]

Pull request overview

Adds process-wide .NET feature-usage telemetry and emits its 128-bit mask through approved Foundry and Azure OpenAI User-Agent pipelines.

Changes:

• Adds feature registry indexes and activation markers across .NET capabilities.
• Adds origin-scoped User-Agent emission with opt-out support.
• Adds registry, activation, concurrency, and emission tests.

Reviewed changes

Copilot reviewed 143 out of 143 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
dotnet/src/Shared/FeatureUsage/UserAgentPolicyRegistration.cs	Adds shared User-Agent policies and origin checks.
dotnet/src/Microsoft.Agents.AI.Abstractions/FeatureUsage.cs	Implements the process-wide feature mask.
dotnet/src/Microsoft.Agents.AI.Abstractions/FeatureIndex.cs	Registers the in-memory history bit.
dotnet/src/Microsoft.Agents.AI.Abstractions/InMemoryChatHistoryProvider.cs	Marks in-memory history usage.
dotnet/src/Microsoft.Agents.AI/FeatureIndex.cs	Registers core feature indexes.
dotnet/src/Microsoft.Agents.AI/ChatClient/ChatClientAgent.cs	Marks core agent execution.
dotnet/src/Microsoft.Agents.AI/Compaction/CompactionProvider.cs	Marks compaction usage.
dotnet/src/Microsoft.Agents.AI/TextSearchProvider.cs	Marks text-search usage.
dotnet/src/Microsoft.Agents.AI/Memory/ChatHistoryMemoryProvider.cs	Marks memory-provider usage.
dotnet/src/Microsoft.Agents.AI/Skills/AgentSkillsProvider.cs	Marks skills-provider participation.
dotnet/src/Microsoft.Agents.AI/Skills/AgentInMemorySkillsSource.cs	Marks in-memory skill loading.
dotnet/src/Microsoft.Agents.AI/Skills/File/AgentFileSkillsSource.cs	Marks file skill discovery.
dotnet/src/Microsoft.Agents.AI/Skills/Programmatic/AgentInlineSkill.cs	Marks inline skill access.
dotnet/src/Microsoft.Agents.AI/Skills/Programmatic/AgentClassSkill.cs	Marks class skill access.
dotnet/src/Microsoft.Agents.AI/Harness/ToolApproval/ToolApprovalAgent.cs	Marks tool-approval execution.
dotnet/src/Microsoft.Agents.AI/Harness/Todo/TodoProvider.cs	Marks todo-provider usage.
dotnet/src/Microsoft.Agents.AI/Harness/FileMemory/FileMemoryProvider.cs	Marks file-memory usage.
dotnet/src/Microsoft.Agents.AI/Harness/FileAccess/FileAccessProvider.cs	Marks file-access usage.
dotnet/src/Microsoft.Agents.AI/Harness/BackgroundAgents/BackgroundAgentsProvider.cs	Marks background-agent usage.
dotnet/src/Microsoft.Agents.AI/Harness/AgentMode/AgentModeProvider.cs	Marks agent-mode usage.
dotnet/src/Microsoft.Agents.AI.Workflows/FeatureIndex.cs	Registers workflow indexes.
dotnet/src/Microsoft.Agents.AI.Workflows/WorkflowBuilder.cs	Marks successful workflow builds.
dotnet/src/Microsoft.Agents.AI.Workflows/SequentialWorkflowBuilder.cs	Marks sequential workflows.
dotnet/src/Microsoft.Agents.AI.Workflows/ConcurrentWorkflowBuilder.cs	Marks concurrent workflows.
dotnet/src/Microsoft.Agents.AI.Workflows/GroupChatWorkflowBuilder.cs	Marks group-chat workflows.
dotnet/src/Microsoft.Agents.AI.Workflows/MagenticWorkflowBuilder.cs	Marks Magentic workflows.
dotnet/src/Microsoft.Agents.AI.Workflows/HandoffWorkflowBuilder.cs	Marks handoff workflows.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/FeatureIndex.cs	Registers declarative workflow usage.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/DeclarativeWorkflowBuilder.cs	Marks successful declarative builds.
dotnet/src/Microsoft.Agents.AI.Foundry/FeatureIndex.cs	Registers Foundry feature indexes.
dotnet/src/Microsoft.Agents.AI.Foundry/FoundryFeatureUsage.cs	Centralizes Foundry marking.
dotnet/src/Microsoft.Agents.AI.Foundry/FoundryChatClient.cs	Marks Foundry requests and toolbox use.
dotnet/src/Microsoft.Agents.AI.Foundry/ClientHeadersAgent.cs	Marks Foundry agent execution.
dotnet/src/Microsoft.Agents.AI.Foundry/Memory/FoundryMemoryProvider.cs	Marks Foundry memory operations.
dotnet/src/Microsoft.Agents.AI.Foundry/Evaluation/FoundryEvals.cs	Marks Foundry evaluations.
dotnet/src/Microsoft.Agents.AI.Foundry/AgentFrameworkUserAgentPolicy.cs	Configures approved Foundry origins.
dotnet/src/Microsoft.Agents.AI.Foundry/Microsoft.Agents.AI.Foundry.csproj	Injects shared User-Agent code.
dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/FeatureIndex.cs	Registers Foundry hosting usage.
dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/ServiceCollectionExtensions.cs	Marks Foundry hosting setup.
dotnet/src/Microsoft.Agents.AI.OpenAI/FeatureIndex.cs	Registers and wraps OpenAI usage.
dotnet/src/Microsoft.Agents.AI.OpenAI/UserAgentPolicies.cs	Configures Azure OpenAI origins.
dotnet/src/Microsoft.Agents.AI.OpenAI/Microsoft.Agents.AI.OpenAI.csproj	Injects shared User-Agent code.
dotnet/src/Microsoft.Agents.AI.OpenAI/Extensions/OpenAIChatClientExtensions.cs	Registers chat policies and markers.
dotnet/src/Microsoft.Agents.AI.OpenAI/Extensions/OpenAIResponseClientExtensions.cs	Registers Responses policies and markers.
dotnet/src/Microsoft.Agents.AI.OpenAI/Extensions/AIAgentWithOpenAIExtensions.cs	Marks OpenAI interoperability calls.
dotnet/src/Microsoft.Agents.AI.OpenAI/ChatClient/AsyncStreamingResponseUpdateCollectionResult.cs	Marks streamed Responses usage.
dotnet/src/Microsoft.Agents.AI.OpenAI/ChatClient/AsyncStreamingChatCompletionUpdateCollectionResult.cs	Marks streamed chat usage.
dotnet/src/Microsoft.Agents.AI.Anthropic/FeatureIndex.cs	Registers and wraps Anthropic usage.
dotnet/src/Microsoft.Agents.AI.Anthropic/AnthropicClientExtensions.cs	Applies Anthropic usage wrappers.
dotnet/src/Microsoft.Agents.AI.Anthropic/AnthropicBetaServiceExtensions.cs	Applies beta Anthropic wrappers.
dotnet/src/Microsoft.Agents.AI.CopilotStudio/FeatureIndex.cs	Registers Copilot Studio usage.
dotnet/src/Microsoft.Agents.AI.CopilotStudio/CopilotStudioAgent.cs	Marks execution and changes session API.
dotnet/src/Microsoft.Agents.AI.GitHub.Copilot/FeatureIndex.cs	Registers GitHub Copilot usage.
dotnet/src/Microsoft.Agents.AI.GitHub.Copilot/GitHubCopilotAgent.cs	Marks execution and simplifies properties.
dotnet/src/Microsoft.Agents.AI.A2A/FeatureIndex.cs	Registers A2A usage.
dotnet/src/Microsoft.Agents.AI.A2A/A2AAgent.cs	Marks execution and changes session APIs.
dotnet/src/Microsoft.Agents.AI.CosmosNoSql/FeatureIndex.cs	Registers Cosmos usage.
dotnet/src/Microsoft.Agents.AI.CosmosNoSql/CosmosCheckpointStore.cs	Marks checkpoint operations.
dotnet/src/Microsoft.Agents.AI.CosmosNoSql/CosmosChatHistoryProvider.cs	Marks Cosmos history operations.
dotnet/src/Microsoft.Agents.AI.Valkey/FeatureIndex.cs	Registers Valkey usage.
dotnet/src/Microsoft.Agents.AI.Valkey/ValkeyChatHistoryProvider.cs	Marks Valkey operations.
dotnet/src/Microsoft.Agents.AI.Mem0/FeatureIndex.cs	Registers Mem0 usage.
dotnet/src/Microsoft.Agents.AI.Mem0/Mem0Client.cs	Marks Mem0 HTTP operations.
dotnet/src/Microsoft.Agents.AI.Purview/FeatureIndex.cs	Registers Purview usage.
dotnet/src/Microsoft.Agents.AI.Purview/PurviewWrapper.cs	Marks Purview processing.
dotnet/src/Microsoft.Agents.AI.Mcp/FeatureIndex.cs	Registers MCP feature indexes.
dotnet/src/Microsoft.Agents.AI.Mcp/McpClientTaskExtensions.cs	Marks MCP tool listing.
dotnet/src/Microsoft.Agents.AI.Mcp/Skills/AgentMcpSkillsSource.cs	Marks MCP skill loading.
dotnet/src/Microsoft.Agents.AI.Declarative/FeatureIndex.cs	Registers declarative agent usage.
dotnet/src/Microsoft.Agents.AI.Declarative/PromptAgentFactory.cs	Marks successful agent creation.
dotnet/src/Microsoft.Agents.AI.Declarative/AggregatorPromptAgentFactory.cs	Marks aggregated factory creation.
dotnet/src/Microsoft.Agents.AI.Declarative/ChatClient/ChatClientPromptAgentFactory.cs	Marks chat-based declarative agents.
dotnet/src/Microsoft.Agents.AI.DevUI/FeatureIndex.cs	Registers DevUI usage.
dotnet/src/Microsoft.Agents.AI.DevUI/DevUIExtensions.cs	Marks DevUI endpoint mapping.
dotnet/src/Microsoft.Agents.AI.Tools.Shell/FeatureIndex.cs	Registers shell-tool usage.
dotnet/src/Microsoft.Agents.AI.Tools.Shell/LocalShellExecutor.cs	Marks local shell execution.
dotnet/src/Microsoft.Agents.AI.Tools.Shell/DockerShellExecutor.cs	Marks Docker shell execution.
dotnet/src/Microsoft.Agents.AI.Hyperlight/FeatureIndex.cs	Registers Hyperlight usage.
dotnet/src/Microsoft.Agents.AI.Hyperlight/HyperlightCodeActProvider.cs	Marks Hyperlight participation.
dotnet/src/Microsoft.Agents.AI.LocalCodeAct/FeatureIndex.cs	Registers local CodeAct usage.
dotnet/src/Microsoft.Agents.AI.LocalCodeAct/LocalCodeActProvider.cs	Marks local CodeAct participation.
dotnet/src/Microsoft.Agents.AI.Harness/FeatureIndex.cs	Registers harness-agent usage.
dotnet/src/Microsoft.Agents.AI.Harness/HarnessAgent.cs	Marks harness execution.
dotnet/src/Microsoft.Agents.AI.Hosting/FeatureIndex.cs	Registers hosting-agent usage.
dotnet/src/Microsoft.Agents.AI.Hosting/AIHostAgent.cs	Marks hosted-agent operations.
dotnet/src/Microsoft.Agents.AI.Hosting.OpenAI/FeatureIndex.cs	Registers OpenAI hosting usage.
dotnet/src/Microsoft.Agents.AI.Hosting.OpenAI/EndpointRouteBuilderExtensions.Responses.cs	Marks Responses endpoint mapping.
dotnet/src/Microsoft.Agents.AI.Hosting.OpenAI/EndpointRouteBuilderExtensions.Conversations.cs	Marks Conversations endpoint mapping.
dotnet/src/Microsoft.Agents.AI.Hosting.OpenAI/EndpointRouteBuilderExtensions.ChatCompletions.cs	Marks chat endpoint mapping.
dotnet/src/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore/FeatureIndex.cs	Registers AG-UI hosting usage.
dotnet/src/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore/AGUIEndpointRouteBuilderExtensions.cs	Marks AG-UI endpoint mapping.
dotnet/src/Microsoft.Agents.AI.Hosting.A2A.AspNetCore/FeatureIndex.cs	Registers A2A hosting usage.
dotnet/src/Microsoft.Agents.AI.Hosting.A2A.AspNetCore/A2AEndpointRouteBuilderExtensions.cs	Marks A2A endpoint mapping.
dotnet/tests/FeatureUsageAssert.cs	Adds shared mask assertions.
dotnet/tests/Directory.Build.props	Links shared assertions into tests.
dotnet/tests/Microsoft.Agents.AI.Abstractions.UnitTests/FeatureUsageTests.cs	Tests mask semantics and formatting.
dotnet/tests/Microsoft.Agents.AI.UnitTests/FeatureUsageActivationTests.cs	Tests core feature activation.
dotnet/tests/Microsoft.Agents.AI.Workflows.UnitTests/WorkflowBuilderTests.cs	Tests workflow activation.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/DeclarativeWorkflowOptionsTest.cs	Tests declarative workflow activation.
dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/PolicyPipelineInvestigationTests.cs	Probes policy ordering and isolation.
dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/FoundryFeatureUsageActivationTests.cs	Tests Foundry activation and emission.
dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/FeatureUsageUserAgentPolicyTests.cs	Tests policy refresh and origin handling.
dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/AgentFrameworkUserAgentPolicyTests.cs	Updates base User-Agent tests.
dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/FoundryChatClientTests.cs	Tests policy registration.
dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/FoundryAgentTests.cs	Tests agent policy registration.
dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Microsoft.Agents.AI.Foundry.UnitTests.csproj	Adds Azure OpenAI test dependency.
dotnet/tests/Microsoft.Agents.AI.Foundry.Hosting.UnitTests/ServiceCollectionExtensionsTests.cs	Tests Foundry hosting activation.
dotnet/tests/Microsoft.Agents.AI.OpenAI.UnitTests/UserAgentPolicyTests.cs	Tests Azure OpenAI emission.
dotnet/tests/Microsoft.Agents.AI.OpenAI.UnitTests/FeatureUsageActivationTests.cs	Tests OpenAI activation.
dotnet/tests/Microsoft.Agents.AI.OpenAI.UnitTests/Microsoft.Agents.AI.OpenAI.UnitTests.csproj	Adds Azure OpenAI test dependency.
dotnet/tests/Microsoft.Agents.AI.Anthropic.UnitTests/FeatureUsageActivationTests.cs	Tests Anthropic activation.
dotnet/tests/Microsoft.Agents.AI.GitHub.Copilot.UnitTests/FeatureUsageActivationTests.cs	Tests GitHub Copilot activation.
dotnet/tests/Microsoft.Agents.AI.GitHub.Copilot.UnitTests/GitHubCopilotAgentTests.cs	Updates session and collection tests.
dotnet/tests/Microsoft.Agents.AI.UnitTests/CopilotStudio/FeatureUsageActivationTests.cs	Tests Copilot Studio activation.
dotnet/tests/Microsoft.Agents.AI.A2A.UnitTests/FeatureUsageActivationTests.cs	Tests A2A activation.
dotnet/tests/Microsoft.Agents.AI.A2A.UnitTests/A2AAgentTests.cs	Updates A2A session tests.
dotnet/tests/Microsoft.Agents.AI.CosmosNoSql.UnitTests/CosmosCheckpointStoreTests.cs	Tests Cosmos activation.
dotnet/tests/Microsoft.Agents.AI.Valkey.UnitTests/FeatureUsageActivationTests.cs	Tests Valkey activation.
dotnet/tests/Microsoft.Agents.AI.Valkey.UnitTests/ValkeyChatHistoryProviderTests.cs	Applies minor test cleanup.
dotnet/tests/Microsoft.Agents.AI.Mem0.UnitTests/FeatureUsageActivationTests.cs	Tests Mem0 activation.
dotnet/tests/Microsoft.Agents.AI.Mem0.UnitTests/Mem0ProviderTests.cs	Applies minor test cleanup.
dotnet/tests/Microsoft.Agents.AI.Purview.UnitTests/FeatureUsageActivationTests.cs	Tests Purview activation.
dotnet/tests/Microsoft.Agents.AI.Purview.UnitTests/PurviewWrapperTests.cs	Applies minor test cleanup.
dotnet/tests/Microsoft.Agents.AI.Mcp.UnitTests/FeatureUsageActivationTests.cs	Tests MCP activation.
dotnet/tests/Microsoft.Agents.AI.Declarative.UnitTests/FeatureUsageActivationTests.cs	Tests declarative agent activation.
dotnet/tests/Microsoft.Agents.AI.DevUI.UnitTests/FeatureUsageActivationTests.cs	Tests DevUI activation.
dotnet/tests/Microsoft.Agents.AI.DevUI.UnitTests/DevUIAccessControlTests.cs	Simplifies middleware test typing.
dotnet/tests/Microsoft.Agents.AI.Tools.Shell.UnitTests/FeatureUsageActivationTests.cs	Tests shell activation.
dotnet/tests/Microsoft.Agents.AI.Hyperlight.UnitTests/FeatureUsageActivationTests.cs	Tests Hyperlight activation.
dotnet/tests/Microsoft.Agents.AI.Hyperlight.UnitTests/ProvideAIContextTests.cs	Updates assignability assertions.
dotnet/tests/Microsoft.Agents.AI.LocalCodeAct.UnitTests/FeatureUsageActivationTests.cs	Tests local CodeAct activation.
dotnet/tests/Microsoft.Agents.AI.LocalCodeAct.UnitTests/LocalCodeActProviderTests.cs	Updates assignability assertion.
dotnet/tests/Microsoft.Agents.AI.Harness.UnitTests/FeatureUsageActivationTests.cs	Tests harness activation.
dotnet/tests/Microsoft.Agents.AI.Hosting.UnitTests/AgentHostingServiceCollectionExtensionsTests.cs	Tests hosted-agent activation.
dotnet/tests/Microsoft.Agents.AI.Hosting.OpenAI.UnitTests/EndpointRouteBuilderExtensionsTests.cs	Tests OpenAI hosting activation.
dotnet/tests/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore.UnitTests/AGUIEndpointRouteBuilderExtensionsTests.cs	Tests AG-UI activation.
dotnet/tests/Microsoft.Agents.AI.Hosting.A2A.UnitTests/A2AEndpointRouteBuilderExtensionsTests.cs	Tests A2A hosting activation.
dotnet/tests/Microsoft.Agents.AI.FeatureRegistry.UnitTests/FeatureRegistryTests.cs	Validates registry declarations and activations.
dotnet/tests/Microsoft.Agents.AI.FeatureRegistry.UnitTests/README.md	Documents registry validation.
dotnet/tests/Microsoft.Agents.AI.FeatureRegistry.UnitTests/Microsoft.Agents.AI.FeatureRegistry.UnitTests.csproj	Adds the registry test project.
dotnet/eng/MSBuild/Shared.props	Adds shared policy source injection.
dotnet/agent-framework-dotnet.slnx	Adds the registry test project.
dotnet/README.md	Documents feature telemetry and opt-out.

Suppressed comments (1)

dotnet/src/Microsoft.Agents.AI.A2A/A2AAgent.cs:91

• This second existing public overload is also changed from instance to static, breaking callers of agent.CreateSessionAsync(contextId, taskId) at both source and binary compatibility levels. Preserve the instance overload (or introduce a differently named static factory) and update the tests to use the compatible API.

    public static ValueTask<AgentSession> CreateSessionAsync(string contextId, string taskId)

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[github-actions]

MAF Automated Review — Iteration 1

Result: Findings reported
Scope: full PR (2 commit(s)): d3b4ded3467c, 38226131e986
Model: gpt-5.6-sol

Overview

The PR implements a process-wide, monotonic feature mask with atomic updates, registry validation, request-time token refresh, an opt-out, and strict direct-request origin checks backed by focused tests. However, automatic redirects can bypass the per-request origin decision and disclose the mask to an unapproved destination. The PR also changes three existing public session-resume methods from instance to static, breaking source and binary compatibility.

Reviewed the supplied pull-request change set across correctness, security/reliability, architecture, and failure behavior.
3 verified findings remained after source verification (2 high, 1 medium) across 3 files. Details are attached to the affected lines below.

Affected areas: dotnet/src/Microsoft.Agents.AI.A2A/A2AAgent.cs, dotnet/src/Microsoft.Agents.AI.CopilotStudio/CopilotStudioAgent.cs, dotnet/src/Shared/FeatureUsage/UserAgentPolicyRegistration.cs