Five projects, one dependency arrow.

The .NET backend is split into five projects with a strictly enforced dependency hierarchy. Build that breaks the rule fails immediately, which is the whole point: dependencies always flow toward the API project, never away from it.

The dependency graph

Reading the graph: Infrastructure has zero project references and may be referenced by anyone. Data sits on top of Infrastructure. Agent and Auth both sit on top of Data + Infrastructure, but they don't see each other. Api sits on top of all four and is the only project that knows about HTTP.

Why this shape

Infrastructure has no DB

So that LangfuseClient, ITokenEncryptor, and Redis primitives can be reused by the MCP service without dragging EF Core along.

Auth doesn't see Agent

JWT issuance, OAuth callbacks, token encryption have nothing to do with the agent loop. Keeping them separate means changes in one cannot ripple into the other.

Agent doesn't see Auth

The agent loop reads userId + tenantId as plain inputs. It never decides who the user is.

Api is the only HTTP layer

Endpoints, WebSocket handlers, DI wiring, and middleware live here. Lower layers are framework-agnostic.

Tests live in one project

tests/AgenticIT.Tests/ with Unit/, Integration/, Parity/. Integration tests use SQLite in-memory via AgenticITWebAppFactory.

What lives where

AgenticIT.Infrastructure

• AgenticITOptions.cs — strongly-typed config (LLM, OAuth, Langfuse, JWT, MCP, MaxToolTurns, …)
• EnvironmentVariableMapper.cs — flat OPENROUTER_API_KEY-style env vars → hierarchical IConfiguration
• ITokenEncryptor — symmetric encryption for stored OAuth / PAT / refresh tokens
• Redis primitives, LangfuseClient, helpers for connection-string parsing

AgenticIT.Data

• AgenticITDbContext.cs — ~95 lines, all DbSets, OnModelCreating applies IEntityTypeConfiguration<T> from the assembly
• Entities/ — ~38 entities (TenantEntity, UserEntity, ChatEntity, ChatMessageEntity, ScheduledJobEntity, SkillEntity, …)
• Configuration/EntityConfigurations.cs — fluent EF mappings, JSONB converters, indexes (incl. partial unique indexes for skills)
• Repositories/ — 40+ interfaces + implementations. Every method returns Dictionary<string, object?> (or a list)

AgenticIT.Agent

• Orchestration/SmartOrchestrator.cs — planner + routing + trace scope
• Loop/SingleAgentLoop.cs — single-agent tool loop (~86 KB)
• Orchestration/SpecialistRunner.cs — parallel specialists + synthesis
• Tools/ToolRegistry.cs, Tools/ToolExecutor.cs — built-in catalog + dispatch
• Mcp/ — IMcpClientManager, McpSession, vBox token refresher
• InstructionModules/ — embedded markdown skill bodies + InstructionModuleLoader
• Approval/ApprovalGate.cs — in-memory destructive-tool gate
• Memory/ — chat title, project summary, user summary, plan / review
• Headless/HeadlessJobRunner.cs — scheduled job execution
• Observability/ — IAgenticITTraceFactory, LangfuseTrace, TracingAnthropicClient
• Credits/CreditsService.cs — pre-call balance check + post-call usage record

AgenticIT.Auth

• JwtService.cs — HMAC-SHA256 signing, claim layout, decode/validate
• OAuthService.cs — Microsoft / Google / GitHub code exchange + refresh
• VboxTokenRefresher.cs — refreshes vBox token on 401
• LocalAuthService.cs, TestUserSeeder.cs — basic auth for dev / test
• TokenEncryptionService.cs — concrete ITokenEncryptor implementation

AgenticIT.Api

• Program.cs — ~78 KB. DI wiring, env-var mapping, OTel setup, schema bootstrap, additive ALTER TABLE statements, endpoint registration
• Endpoints/* — 30+ RouteGroupBuilder extension files (chat, project, artifact, config, admin, scheduled, vbox, msgraph, …)
• WebSockets/ChatWebSocketHandler.cs — auth, channel attach, orchestrator launch
• WebSockets/StopWatchdog.cs — 5-second guarantee on user-initiated stops

Cross-cutting rules

Where to dive