๐ Backend API Library Blueprint¶
๐งญ Introduction and Purpose¶
The Backend API Library Blueprint defines how the AI Software Factory generates reusable, production-ready libraries for interacting with external or internal APIs. These libraries are created from a blueprint definition and implemented via the .NET Core CLI template named:
This blueprint enables agents to rapidly scaffold API client libraries that follow ConnectSoft principles โ enabling strong typing, resiliency, observability, and security-first access to remote endpoints.
๐ฏ Purpose¶
The blueprint serves to:
- Encapsulate access to REST, GraphQL, gRPC, or proprietary APIs
- Provide a typed HTTP interface for application services and other agents
- Enable standard configuration, auth, logging, retry policies, etc.
- Package libraries into NuGet-distributable modules
- Include ready-to-run mock servers and test harnesses for integration and contract testing
- Document all capabilities via auto-generated usage guides and integration samples
๐ญ Use in the Software Factory¶
The blueprint is used when:
| Scenario | Trigger |
|---|---|
| โ A service needs to consume an external API | Business Analyst Agent or Solution Architect defines integration need |
| โ A domain module needs to publish an internal service client | Domain Architect Agent defines module boundary |
| โ A third-party service is required in multiple modules | API Engineer Agent declares shared reusable SDK |
| โ An AI agent needs to wrap its own function via HTTP | Tooling Agent emits client to call its own generated service |
๐ฆ Typical Output Artifacts¶
| Artifact | Description |
|---|---|
ConnectSoft.MyCompany.GoogleAnalyticsClient.dll |
Compiled NuGet package |
Http.GoogleAnalyticsClient.cs |
Strongly typed wrapper around HttpClient |
GoogleAnalyticsOptions.cs |
Binds to configuration (e.g., API key, base URL) |
IGoogleAnalyticsClient.cs |
Interface-first design |
tests/ |
Unit + integration tests |
mock-server/ |
Optional stub/mock implementation for testing pipelines |
README.md |
Usage guide with samples |
azure-pipelines.yml |
CI build/test/publish workflow |
๐ก Blueprint Pattern Class¶
This blueprint belongs to:
- ๐งฉ Type:
library.blueprint.backend.api - ๐งช Domain:
sdk,external-integration,internal-client - ๐ Pattern:
agentic.library.contract+http+resilience+telemetry
๐ Related Blueprints¶
| Related Blueprint | Purpose |
|---|---|
frontend-library-blueprint.md |
Consumed from frontend codebases (optional proxy wrapper) |
platform-blueprint.md |
May use this library as a package in the host |
agent-microservice-blueprint.md |
Can generate the server-side implementation for this client |
โ Summary¶
The Backend API Library Blueprint standardizes how API clients are created, tested, documented, and published as reusable modules in the platform. It combines strong architectural patterns with agent automation, enabling scalable integration at speed.
๐งญ Key Principles and Design Alignment¶
This blueprint is deeply aligned with the foundational principles of the ConnectSoft AI Software Factory, ensuring that every generated API library is cleanly structured, modular, observable, and secure by design.
๐งฑ Clean Architecture Alignment¶
The backend API library generated by this blueprint follows Clean Architecture by:
- Isolating the HTTP logic in
Infrastructurelayer (no leakage into Domain) - Providing clear interfaces (
I*Client.cs) for injection - Ensuring no business logic resides in the library โ it acts as a data access boundary
๐ Example structure:
src/
- GoogleAnalyticsClient/
- IGoogleAnalyticsClient.cs
- GoogleAnalyticsClient.cs
- GoogleAnalyticsOptions.cs
- Http/
- Extensions/
- Configuration/
๐งฉ Domain-Driven Design (DDD) Principles¶
- Clients are named after bounded contexts or external APIs (
Analytics,Payments,CRM) - Optionally include value objects or response DTOs (from OpenAPI or manually modeled)
- Designed to fit cleanly inside domain service layers, not UI or infrastructure mixing
๐ Event-Driven and Observable¶
-
Out-of-the-box support for emitting:
-
HttpRequestStarted,HttpRequestFailed,HttpResponseReceivedevents - Trace IDs injected via middleware
- Metrics for latency, retry count, success/failure rate
These events flow into:
- Azure Application Insights
- OpenTelemetry pipelines
- Event Mesh (Kafka/Event Grid) for distributed tracing
๐ก Observability-First Design¶
| Capability | Included? | Notes |
|---|---|---|
| Structured Logging | โ | Serilog sinks, context-rich logs |
| Distributed Tracing | โ | Uses trace/context propagation middleware |
| Metrics (Latency, Errors) | โ | Default Prometheus exporters supported |
| Retry/Audit Events | โ | Logged and tracked |
๐งฐ Modular, Composable, Extensible¶
- Each client library is a self-contained package
- Optional plugins:
ICacheHandler,IRetryPolicy,IRequestSigner - Support for dependency injection via
.AddGoogleAnalyticsClient()style extension
๐งฉ Supports integration with:
- OpenId Connect libraries
- Configuration providers (Azure App Config, Vaults)
- Testing/mocking frameworks
๐ก Security-First Architecture¶
- No secrets are hardcoded โ all credentials injected via
IOptions - Supports bearer token injection, API key headers, and OIDC delegation
- Optional rate limiting, circuit breaking, IP restrictions
๐ง AI-Aware Blueprint Design¶
- Blueprint includes prompts for:
- API docs ingestion
- Response/DTO modeling from samples
- Retry policy generation
- Memory stores track failures, usage feedback, agent improvements
โ Summary¶
The backend API library blueprint doesnโt just scaffold code โ it embeds best practices from Clean Architecture, DDD, observability, and modular thinking into every line. Every agent using this blueprint builds libraries that are secure, testable, observable, and production-ready โ by default.
๐งญ Generation Source: Template CLI and Blueprint Definition¶
This section explains the technical origin of the backend API library blueprint: it is instantiated via a specialized .NET CLI template and configured through an AI-readable blueprint definition. The combination enables fully agentic, repeatable scaffolding with predictable structure and metadata.
โ๏ธ .NET CLI Template¶
The blueprint is implemented via the ConnectSoft CLI template:
This template generates a complete multi-project solution:
| Project | Description |
|---|---|
GoogleAnalyticsClient |
Main API logic and client |
GoogleAnalyticsClient.Tests |
Unit and integration test project |
GoogleAnalyticsClient.MockServer |
Optional mock service for local and CI testing |
GoogleAnalyticsClient.Configuration |
Strongly typed Options and DI extensions |
.factory/ |
Blueprint metadata and traceability context |
๐ง Input: Blueprint DSL / YAML¶
The generation process is driven by a YAML blueprint definition like this:
id: ConnectSoft.Backend.GoogleAnalyticsClient
type: backend.api.library
template: connectsoft-api-library
parameters:
baseUrl: "https://analytics.googleapis.com/v1"
authentication: oauth2
retryPolicy: true
traceIntegration: true
optionsBinding: true
metadata:
createdBy: ApiScaffolderAgent
originatingRunId: RUN-2025-06-07-001
This DSL is parsed by the agent, and prompts are shaped accordingly to guide the CLI invocation and post-processing.
โ๏ธ Template Features Supported¶
| Feature | Supported? | Source |
|---|---|---|
Typed HttpClient |
โ | Scaffolded via base template |
| DI Extensions | โ | AddGoogleAnalyticsClient(IServiceCollection) |
| Test Templates | โ | MSTest, Moq, AutoFixture |
| Retry + Resilience | โ | Optional flag in DSL |
| Config Binding | โ | .UseGoogleAnalyticsOptions() |
| Telemetry Hooks | โ | OpenTelemetry/Serilog pre-wired |
| NuGet Packaging | โ | pack task and nuspec auto-filled |
๐ง Output: Traceability Context¶
Every generated project includes .factory/blueprint.meta.json:
{
"id": "ConnectSoft.Backend.GoogleAnalyticsClient",
"template": "connectsoft-api-library",
"agent": "ApiScaffolderAgent",
"createdAt": "2025-06-07T13:52:00Z",
"parameters": {
"authentication": "oauth2",
"retryPolicy": true
}
}
This enables regeneration, memory linking, reuse, and documentation automation.
๐ README.md Snippet from Template¶
# ๐ฆ GoogleAnalyticsClient
This package is an API wrapper for Google Analytics v4, generated from the ConnectSoft backend API blueprint.
- Built with: `connectsoft-api-library` template
- Auth: OAuth2
- Retry Policy: Enabled
- Observability: Tracing, Logging, Metrics
โ Summary¶
This blueprint is powered by a robust .NET CLI template, enriched by a blueprint YAML definition and consumed by agents. It allows precise, repeatable, traceable scaffolding of fully featured backend libraries โ minimizing manual effort while enforcing ConnectSoft standards.
๐งญ High-Level Folder and Project Layout¶
This section defines the output structure of the backend API library generated from the blueprint. The layout ensures separation of concerns, easy testing, modular reuse, and clear alignment with Clean Architecture practices.
๐ Solution Folder Structure¶
When the blueprint is executed via CLI, the following structure is generated:
GoogleAnalyticsClient/
โโโ src/
โ โโโ GoogleAnalyticsClient/
โ โ โโโ Clients/
โ โ โโโ Configuration/
โ โ โโโ Extensions/
โ โ โโโ Models/
โ โ โโโ Requests/
โ โ โโโ Responses/
โ โ โโโ Services/
โ โ โโโ Authentication/
โ โ โโโ GoogleAnalyticsClient.csproj
โ โโโ GoogleAnalyticsClient.MockServer/
โ โโโ Controllers/
โ โโโ Fixtures/
โ โโโ GoogleAnalyticsClient.MockServer.csproj
โโโ tests/
โ โโโ GoogleAnalyticsClient.UnitTests/
โ โโโ Builders/
โ โโโ Integration/
โ โโโ Unit/
โ โโโ Fixtures/
โ โโโ GoogleAnalyticsClient.UnitTests.csproj
โโโ blueprints/
โ โโโ blueprint.yaml
โโโ .factory/
โ โโโ blueprint.meta.json
โโโ README.md
โโโ azure-pipelines.yml
๐ฆ Key Subfolders Explained¶
| Folder | Purpose |
|---|---|
Clients/ |
Implements the actual HTTP interface logic |
Requests/Responses/Models/ |
Strongly typed DTOs for API input/output |
Configuration/ |
Contains Options classes and DI extension methods |
Authentication/ |
Encapsulates OAuth2/API Key injectors |
Extensions/ |
Fluent service registration and pipeline wiring |
Services/ |
Higher-level business wrapper if needed (optional) |
MockServer/ |
Fake/stubbed API service for local testing and CI |
Tests/ |
Test projects organized by type (unit/integration/etc.) |
.factory/ |
Metadata and trace logs for blueprint lineage |
๐งฉ Layer Alignment¶
| Layer | Location |
|---|---|
| Infrastructure | Clients/, Authentication/, Http/ |
| Application | Services/, Options/, Configuration/ |
| Test/Mocking | Tests/, MockServer/ |
| Blueprint/CI | .factory/, azure-pipelines.yml |
๐ README Structure (Auto-Generated)¶
# GoogleAnalyticsClient
> ConnectSoft standard backend API library
## ๐ Installation
```bash
dotnet add package ConnectSoft.GoogleAnalyticsClient
```
## ๐ Usage
```csharp
services.AddGoogleAnalyticsClient(Configuration);
```
## ๐ฆ Structure
* Requests/Responses: Typed DTOs
* Clients: Typed `HttpClient` wrappers
* Config: OAuth2 and endpoint settings
โ Summary¶
The high-level layout of the backend API library is modular, extensible, and clean โ giving agents, developers, and testers a predictable and powerful starting point. This structure ensures that authentication, requests, configuration, and testing are separated but integrated, enabling rapid development and safe reuse.
๐งญ Artifact Types Produced by the Blueprint¶
This section outlines the full set of runtime and development artifacts generated by the backend API library blueprint. These outputs are standardized across the factory to ensure portability, traceability, observability, and reuse within ConnectSoftโs modular ecosystem.
๐ฆ Artifact Overview¶
| Artifact Type | Output File or Format | Purpose |
|---|---|---|
| ๐งฑ NuGet Package | ConnectSoft.GoogleAnalyticsClient.nupkg |
Reusable, publishable .NET client package |
| ๐งช Test Binaries | GoogleAnalyticsClient.Tests.dll |
Unit/integration test output |
| ๐ Telemetry Hooks | ILogger, Activity, metrics emitters |
Observability-first instrumentation |
| ๐ Config Template | GoogleAnalyticsOptions.cs, appsettings.json snippet |
Config-driven setup (base URL, keys, scopes) |
| ๐ Documentation | README.md, features.md, Usage.md, Authentication.md |
Agent-generated guides |
| โ๏ธ CI/CD Pipeline | azure-pipelines.yml or ci.yaml |
Ready-to-use DevOps YAML pipeline |
| ๐ Mock Server | GoogleAnalyticsClient.MockServer.dll, Dockerfile (optional) |
Simulated API for contract & integration testing |
| ๐ง Trace Metadata | .factory/blueprint.meta.json |
Traceable execution context |
| ๐งฌ DSL Blueprint | blueprints/blueprint.yaml |
The blueprint that defines and reproduces the library |
| ๐ค OpenAPI Snapshots | openapi.schema.json (optional) |
Used when syncing API clients with server definitions |
๐ง Deep Integration into Factory Memory¶
Every artifact is:
- Tagged by its
blueprint.id, version, and agent origin - Stored in:
- Azure Artifacts (NuGet feed)
- Azure DevOps pipeline storage
- Vector DB for embedding and reuse search
- Linked to its original
AgentRunIdand DSL input
This enables:
- Auditability of generated components
- Full regeneration from metadata
- Memory-based similarity search (e.g., โFind clients similar to this oneโ)
๐ Sample Artifact Directory Tree¶
dist/
โโโ ConnectSoft.GoogleAnalyticsClient.1.0.0.nupkg
โโโ test-results.xml
โโโ doc/
โ โโโ README.md
โ โโโ Authentication.md
โ โโโ Configuration.md
โ โโโ Usage.md
โโโ .factory/
โ โโโ blueprint.meta.json
โโโ mock-server/
โ โโโ docker-compose.yml
โ โโโ GoogleAnalyticsClient.MockServer.dll
๐ง Agents Producing Artifacts¶
| Agent | Artifact |
|---|---|
| LibraryScaffolderAgent | .NET projects, main code layout |
| DocsAgent | Markdown and usage docs |
| MockServerAgent | Fake implementation & API test targets |
| PipelineAgent | azure-pipelines.yml, NuGet pack and push |
| MemoryIndexerAgent | Pushes .meta.json and DSL into trace memory |
| TestGeneratorAgent | MSTest suites, stubs, mocks |
๐งฉ Example Use: App Consumes Published NuGet¶
services.AddGoogleAnalyticsClient(configuration);
var client = serviceProvider.GetRequiredService<IGoogleAnalyticsClient>();
await client.TrackEventAsync("campaign");
โ Summary¶
The backend API library blueprint produces more than just code โ it yields a full constellation of publishable, observable, testable artifacts that can be consumed across microservices, apps, and agents. These outputs are machine-traceable and composable โ making every API client a secure, reusable module in the ConnectSoft software ecosystem.
๐งญ When to Use This Blueprint¶
This section defines when and why an agent or engineer should instantiate the backend API library blueprint. It helps differentiate its use from other blueprint types (e.g. microservices, frontend libraries) and clarifies best-fit scenarios across system architecture and product needs.
๐งฉ Primary Use Cases¶
| Scenario | Use This Blueprint |
|---|---|
| โ A backend service needs to call an external 3rd-party API | YES โ Generate a secure, typed HTTP client wrapper |
| โ An internal domain module wants to expose a reusable service interface | YES โ Produce a NuGet SDK-style library |
| โ An AI agent wraps a service it generates via REST | YES โ Creates a usable interface for self-call or downstream agents |
| โ A service hosts endpoints and needs to scale independently | โ Use the agent-microservice-blueprint.md |
| โ A UI consumes APIs directly via TypeScript or Blazor | โ Use the frontend-library-blueprint.md |
| โ Common tenant-aware services (e.g. billing, audit) consumed by many apps | YES โ Abstract client logic into a library with shared responsibility |
๐ฏ Ideal Blueprint Characteristics¶
- โ Pull-based communication (client โ service)
- โ Reusable logic across services or apps
- โ No need for database or hosting runtime
- โ Strong need for authentication, observability, retries
- โ Output is a NuGet-distributed .NET library
๐ง Triggering Agents¶
| Agent | Triggering Condition |
|---|---|
| Business Analyst Agent | Identifies integration need with external API |
| Solution Architect Agent | Models boundary between services and suggests reuse |
| Platform Agent | Extracts shared logic from multiple microservices |
| DevOps Agent | Creates standard pipelines and artifacts for API integration |
| AI Runtime Agent | Needs to expose or consume a backend function securely |
๐ Examples¶
| Case | Result |
|---|---|
| ๐งพ CRM system wants to push customer events to Segment | Generates SegmentClient with OAuth2 |
| ๐งพ Payment Service needs to call Stripe API | Generates StripeClient with API key support |
| ๐งพ Tenant Management needs to centralize billing across apps | Generates reusable TenantBillingClient NuGet |
| ๐งพ AI Agent wraps an internal retry-and-queue system | Outputs RetryClient used in runtime orchestration |
๐งฉ Library vs. Microservice Decision¶
| Feature | Library Blueprint | Microservice Blueprint |
|---|---|---|
| Hosting runtime | โ No | โ Yes |
| External HTTP endpoints | โ No | โ Yes |
| Pulls external data | โ Yes | โ No |
| Reused across other modules | โ Yes | โ Rarely |
| Deployed independently | โ No | โ Yes |
| Published as NuGet | โ Yes | โ No |
โ Summary¶
The backend API library blueprint is ideal for producing typed, authenticated, observable client wrappers for remote APIs โ internal or external. It enables reuse, testing, and CI/CD at the library level, without the burden of full microservice deployment. It is the default choice whenever your service needs to consume other services reliably and securely.
๐งญ Blueprint DSL and Configurable Parameters¶
This section describes the blueprint definition schema (DSL) used by agents to instantiate and configure backend API libraries. The DSL allows agents to declaratively define the behavior, dependencies, security, and observability expectations of the generated library โ before code is written.
๐ Sample DSL Snippet¶
id: ConnectSoft.Backend.StripeClient
type: backend.api.library
template: connectsoft-api-library
parameters:
baseUrl: "https://api.stripe.com/v1"
authentication:
type: apiKey
headerName: "Authorization"
prefix: "Bearer "
retryPolicy:
strategy: exponentialBackoff
maxAttempts: 5
telemetry:
enabled: true
tracing: true
metrics: true
options:
enabled: true
bindFrom: "Stripe:Client"
environments:
- Development
- Production
๐ง Supported Parameters¶
| Parameter | Description | Example |
|---|---|---|
baseUrl |
Base endpoint of the API | https://api.stripe.com/v1 |
authentication |
Auth strategy (API key, OAuth2, custom) | apiKey, oauth2 |
retryPolicy |
Retry/backoff config | exponentialBackoff, linear, none |
telemetry |
Enable logs, traces, metrics | enabled: true |
options |
Bind config to IOptions<T> |
Bind from appsettings |
environments |
List of supported environments | Development, Staging, Production |
headers |
Custom headers to inject | { x-api-version: "v1" } |
rateLimiting |
Enable local rate limiter | enabled: true, window: 1s, max: 10 |
๐ง DSL Usage in Agent Prompts¶
Agents use the DSL fields to:
- Shape prompt for client method extraction:
- e.g.,
"Here is the OpenAPI spec and base URL. GenerateIAnalyticsClientinterface using baseUrl from DSL."
- e.g.,
- Inject conditional logic:
- If
authentication.type = oauth2, scaffold token providers andAuthorizationHandler
- If
- Compose observability config:
- Telemetry decorators inserted only if
telemetry.enabled = true
- Telemetry decorators inserted only if
- Choose environment-specific overrides:
- E.g., use mock baseUrl in
Development
- E.g., use mock baseUrl in
๐งฉ Modular Extensions¶
The DSL is composable โ additional blueprint fragments can extend the base spec:
Agents can use shared fragments (stored in vector memory or blob) to apply reusable patterns.
๐งฌ Versioned DSL¶
Each blueprint can be versioned and replayed. DSLs are saved into:
.factory/blueprint.meta.jsonblueprints/blueprint.yaml- Memory vector index for lookup and regeneration
๐ Validated DSL Schema (JSON)¶
Blueprints follow a schema-compatible structure and are validated prior to generation:
{
"type": "object",
"required": ["id", "template", "parameters"],
"properties": {
"authentication": {
"type": "object",
"properties": {
"type": { "enum": ["apiKey", "oauth2", "custom"] },
"headerName": { "type": "string" }
}
}
}
}
โ Summary¶
The DSL gives agents declarative control over how an API library is structured, secured, and wired. It ensures reproducibility, allows conditional prompt logic, and supports memory-driven reuse of patterns across blueprints. Itโs the foundation of blueprint-driven scaffolding in the ConnectSoft AI Software Factory.
๐งญ Example Instantiation Flow: From DSL to Working Library¶
This section illustrates a complete agentic instantiation flow of the backend API library blueprint โ starting from an integration need, through DSL definition and prompt orchestration, to a fully generated, testable, publishable client library.
๐ Scenario: Stripe API Integration¶
"The Product Owner requests secure, reusable access to the Stripe Billing API for recurring subscriptions."
๐ง Step-by-Step Agent Flow¶
| Step | Agent | Action |
|---|---|---|
| 1๏ธโฃ | Business Analyst Agent | Captures requirement: "Integrate with Stripe to manage customer subscriptions." |
| 2๏ธโฃ | Solution Architect Agent | Decides to isolate Stripe access into a standalone client |
| 3๏ธโฃ | LibraryScaffolderAgent | Prepares DSL and emits it into prompt |
| 4๏ธโฃ | Code Generator Agent | Generates structure using connectsoft-api-library |
| 5๏ธโฃ | Authentication Agent | Adds API key support based on DSL config |
| 6๏ธโฃ | RetryPolicy Agent | Adds exponential backoff decorators |
| 7๏ธโฃ | Observability Agent | Wraps methods with logs, traces, and metrics |
| 8๏ธโฃ | Docs Agent | Generates README.md, Authentication.md, Usage.md |
| 9๏ธโฃ | Pipeline Agent | Adds azure-pipelines.yml for build + publish |
| ๐ | MemoryIndexerAgent | Stores blueprint metadata, DSL, and artifacts for future reuse |
๐ Input DSL¶
id: ConnectSoft.Backend.StripeClient
template: connectsoft-api-library
parameters:
baseUrl: "https://api.stripe.com/v1"
authentication:
type: apiKey
headerName: "Authorization"
prefix: "Bearer "
telemetry:
enabled: true
tracing: true
metrics: true
retryPolicy:
strategy: exponentialBackoff
maxAttempts: 4
๐๏ธ CLI Generation¶
Produces:
StripeClient/StripeClient.Tests/StripeClient.MockServer/.factory/blueprint.meta.json
๐งช Example Generated Interface¶
public interface IStripeClient
{
Task<CustomerResponse> GetCustomerAsync(string customerId, CancellationToken cancellationToken = default);
Task<InvoiceResponse> CreateInvoiceAsync(CreateInvoiceRequest request, CancellationToken cancellationToken = default);
}
๐ Sample Usage (Consumer App)¶
services.AddStripeClient(Configuration);
var stripe = sp.GetRequiredService<IStripeClient>();
var invoice = await stripe.CreateInvoiceAsync(new CreateInvoiceRequest { ... });
๐ Generated README (Excerpt)¶
# StripeClient
> ConnectSoft API client for Stripe Billing v1
## ๐ Authentication
This client uses Bearer token-based API key auth.
Set in `appsettings.json`:
```json
"Stripe": {
"ApiKey": "sk_test_123456..."
}
```
## ๐ฆ Installation
```bash
dotnet add package ConnectSoft.StripeClient
```
๐ Trace Metadata¶
Saved in .factory/blueprint.meta.json:
{
"id": "ConnectSoft.Backend.StripeClient",
"agent": "LibraryScaffolderAgent",
"originatingRunId": "RUN-2025-06-07-024",
"parameters": {
"authentication": "apiKey",
"retryPolicy": "exponentialBackoff"
}
}
โ Summary¶
This example shows how a simple DSL blueprint can drive an automated, production-grade API integration โ complete with authentication, retries, observability, CI/CD, tests, and documentation. The entire flow is reproducible, traceable, and memory-indexed for future reuse or mutation.
๐งญ Cross-Blueprint Dependencies and Shared Integrations¶
This section explains how backend API libraries generated by this blueprint can depend on, extend, or compose with other blueprints โ forming modular, reusable service SDKs that integrate deeply across the ConnectSoft platform.
๐ Cross-Blueprint Relationship Map¶
graph TD
B[Backend API Library]
F[Frontend Library Blueprint]
M[Microservice Blueprint]
P[Platform Blueprint]
O[Observability Blueprint]
C[Configuration Blueprint]
T[Testing Blueprint]
B --> O
B --> C
B --> T
F --> B
M --> B
P --> B
๐งฉ Typical Dependencies¶
| Blueprint | Integration Mode | Description |
|---|---|---|
observability-blueprint.md |
Decorators / DI hooks | Logging, tracing, metrics injected into client |
configuration-blueprint.md |
Options pattern | Auto-binds appsettings.json or Vault |
testing-blueprint.md |
Test base, mocks | Used to generate mock servers and test doubles |
frontend-library-blueprint.md |
API shape mirroring | Shared DTOs or signature alignment |
agent-microservice-blueprint.md |
Server implementation | Generated library may call generated microservice |
platform-blueprint.md |
Compositional reuse | Library injected as NuGet into platform host apps |
๐ Blueprint Reuse Example¶
๐ StripeClient is consumed in:
TenantBillingService(microservice blueprint)ConnectSoft Platform(platform blueprint)TenantPortalWebApp(frontend blueprint via proxy bridge)
๐ง Agent-Level Collaboration¶
| Producer Agent | Consuming Agent |
|---|---|
LibraryScaffolderAgent |
DocsAgent, PipelineAgent |
AuthInjectorAgent |
ObservabilityAgent |
MockServerAgent |
TestGeneratorAgent |
PlatformOrchestratorAgent |
Reuses NuGet from API library blueprint |
This interaction is orchestrated by blueprint dependency graphs, where each artifact carries a dependsOn metadata block.
๐ Blueprint Metadata Extension¶
{
"id": "ConnectSoft.Backend.StripeClient",
"dependsOn": [
"blueprint.configuration.standard",
"blueprint.observability.default",
"blueprint.testing.mstest"
]
}
This allows agents to automatically resolve and inject additional blueprints or capabilities during generation.
๐ฆ Shared Packages/Artifacts¶
Generated backend API libraries may depend on shared ConnectSoft nugets such as:
| NuGet Package | Purpose |
|---|---|
ConnectSoft.Extensions.Http.OpenIdConnect |
Token handler for OIDC flows |
ConnectSoft.Resilience |
Retry, circuit breaker decorators |
ConnectSoft.Observability.Core |
Logging, tracing, metrics hooks |
ConnectSoft.Testing.MockServer |
Prebuilt HTTP mocks and assert helpers |
๐ Output Folder Enrichment¶
Blueprints may co-locate shared components or emit them into the same workspace for local linking:
/src/
StripeClient/
ConnectSoft.Observability.Core/ <-- Injected from observability blueprint
ConnectSoft.Configuration.Shared/
โ Summary¶
The backend API library blueprint is not isolated โ it is composable and interconnected with the larger platform via blueprint dependencies, shared agents, and layered artifact reuse. This makes it scalable, traceable, and evolvable โ while minimizing code duplication and siloed integrations.
๐งญ Typed HTTP Client Design and Interface Generation¶
This section focuses on how the blueprint generates typed, testable, and DI-ready HTTP clients. These clients are scaffolded with explicit interfaces, clean request/response models, and extensible behavior hooks โ enabling composable and resilient backend API access.
๐ง Interface-First Design Pattern¶
The generated client adheres to the interface-first principle:
public interface IStripeClient
{
Task<CustomerResponse> GetCustomerAsync(string customerId, CancellationToken ct = default);
Task<InvoiceResponse> CreateInvoiceAsync(CreateInvoiceRequest request, CancellationToken ct = default);
}
The implementation:
public class StripeClient : IStripeClient
{
private readonly HttpClient client;
public StripeClient(HttpClient client)
{
this.client = client;
}
public async Task<CustomerResponse> GetCustomerAsync(string customerId, CancellationToken ct)
{
var response = await client.GetAsync($"/customers/{customerId}", ct);
response.EnsureSuccessStatusCode();
return await response.Content.ReadFromJsonAsync<CustomerResponse>(cancellationToken: ct);
}
}
๐๏ธ Generated via Agentic Template¶
- Interface and class are generated from:
- OpenAPI spec
- Sample JSON
- User-defined prompt
- Optional fallback: agents prompt GPT to infer methods from API doc text
๐งฉ Benefits of Interface-First Approach¶
| Benefit | Description |
|---|---|
| ๐งช Testability | Allows mocking of IStripeClient in unit tests |
| ๐ Swappability | Can replace implementation at runtime (e.g., mock, proxy) |
| ๐ง LLM Reasoning | Simplifies reflection, traceability, and behavioral prompts |
| ๐ DI Compatibility | Plugs into factory-wide AddXyzClient() extensions |
| ๐ Auto-docs | Enables agents to generate usage snippets from method signature |
๐ Typed HttpClient Injection¶
The client is registered via DI:
services.AddHttpClient<IStripeClient, StripeClient>()
.ConfigureHttpClient((sp, client) =>
{
var opts = sp.GetRequiredService<IOptions<StripeOptions>>().Value;
client.BaseAddress = new Uri(opts.BaseUrl);
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", opts.ApiKey);
})
.AddPolicyHandler(RetryPolicies.ExponentialBackoff());
This supports:
- โ Resiliency decorators
- โ
Telemetry middleware (e.g.,
TracingHandler) - โ Config-driven headers and base URLs
๐ Project Layout¶
| Folder | Contents |
|---|---|
Clients/ |
IStripeClient.cs, StripeClient.cs |
Models/ |
DTOs such as InvoiceRequest, CustomerResponse |
Authentication/ |
Token and header injectors |
Configuration/ |
StripeOptions.cs, IOptions<StripeOptions> |
๐ง AI Prompt Sample¶
You are the API Client Agent.
You are given:
- baseUrl: https://api.stripe.com/v1
- Auth type: API Key in Bearer header
- Required methods: create invoice, get customer
Produce:
- `IStripeClient` interface
- `StripeClient` implementation
- Typed models in `Requests/` and `Responses/`
- DI registration extension
โ Summary¶
Typed HTTP clients are the core output artifact of the backend API blueprint. They expose clean, versioned, observable interfaces with testability, DI support, and resiliency built-in โ enabling the factory to scale integrations without sacrificing maintainability.
๐งญ Authentication and Authorization Strategies¶
This section defines the authentication mechanisms supported by the backend API library blueprint and how they are injected, abstracted, and configured during agentic generation. These strategies ensure secure access to both internal and external services in a reusable and pluggable way.
๐ Supported Auth Strategies¶
| Strategy | Description | Example Use |
|---|---|---|
apiKey |
Static key passed in a header or query param | Stripe, SendGrid, Mailchimp |
oauth2-client-credentials |
Machine-to-machine OAuth 2.0 flow | Microsoft Graph, Salesforce, HubSpot |
openIdConnect |
Identity tokens, user delegation | Azure AD, Auth0 |
custom |
Agent-defined injectors, dynamic headers | Partner APIs, legacy systems |
๐ง DSL Example¶
authentication:
type: oauth2-client-credentials
tokenUrl: https://login.microsoftonline.com/tenant/oauth2/v2.0/token
clientId: __from_config__
clientSecret: __from_keyvault__
scope: https://graph.microsoft.com/.default
๐งฉ Injection via Decorator Handlers¶
The generated client uses delegating handlers to insert tokens automatically:
public class OAuth2AuthorizationHandler : DelegatingHandler
{
private readonly ITokenProvider tokenProvider;
public OAuth2AuthorizationHandler(ITokenProvider tokenProvider) =>
this.tokenProvider = tokenProvider;
protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
var token = await tokenProvider.GetAccessTokenAsync();
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
return await base.SendAsync(request, cancellationToken);
}
}
Registered via DI:
services.AddTransient<OAuth2AuthorizationHandler>();
services.AddHttpClient<IMyClient, MyClient>()
.AddHttpMessageHandler<OAuth2AuthorizationHandler>();
๐ API Key Configuration¶
For simpler APIs using static keys:
API keys are securely bound via IOptions<T>:
๐ง Token Providers and Reuse¶
Agents may inject:
IClientCredentialTokenProviderfor OAuth2 client flowIOpenIdConnectTokenProviderfor ID tokensICustomHeaderInjectorfor proprietary logic
These are shared across libraries and available as reusable nugets.
๐ Token Caching¶
The blueprint integrates with a platform-wide caching layer:
| Feature | Behavior |
|---|---|
| Memory Cache | Default per-process access token reuse |
| Distributed Cache | Optional for clustered environments |
| Token TTL Awareness | Respects expires_in from token response |
๐ Secrets and Key Vault Support¶
The blueprint never hardcodes secrets. It supports:
- Azure Key Vault via:
ISecretProvider- Configuration binding from
Managed Identity
- Local secrets via
.usersecrets - CI-injected secrets via pipeline variables
โ Summary¶
Authentication in the backend API library blueprint is flexible, pluggable, and composable. Agents configure it via DSL, and the scaffolded client ensures proper injection, caching, and reuse of credentials โ across APIs and runtime environments โ without security compromises.
๐งญ Resiliency Layer: Retries, Circuit Breakers, Bulkheads¶
This section outlines how the backend API library blueprint integrates resiliency patterns to ensure robustness and fault tolerance when communicating with remote APIs โ including automatic retries, fallback strategies, timeout handling, and optional circuit breakers.
๐งฐ Resiliency Features Built-In¶
| Capability | Included | Description |
|---|---|---|
| โ Retry Policies | โ๏ธ | Retry transient failures (e.g., HTTP 429, 503) |
| โ Timeout Policies | โ๏ธ | Abort long-running requests gracefully |
| โ Circuit Breakers | โณ Opt-in | Stop requests temporarily after repeated failures |
| โ Bulkhead Isolation | โณ Opt-in | Limit concurrency for expensive endpoints |
These behaviors are injected via HttpClient policies and are configurable through DSL or DI.
๐ง DSL Configuration Example¶
retryPolicy:
strategy: exponentialBackoff
maxAttempts: 5
delay: 1s
jitter: true
circuitBreaker:
enabled: true
failureThreshold: 10
breakDuration: 30s
โ๏ธ Resiliency Implementation (Polly)¶
Generated code uses Polly or platform-specific wrappers:
services.AddHttpClient<IStripeClient, StripeClient>()
.AddPolicyHandler(Policy<HttpResponseMessage>
.Handle<HttpRequestException>()
.OrResult(r => r.StatusCode == HttpStatusCode.TooManyRequests)
.WaitAndRetryAsync(5, retryAttempt =>
TimeSpan.FromSeconds(Math.Pow(2, retryAttempt))
));
๐ Other strategies:
Retry-Afterheader aware- Circuit breaker:
.AddPolicyHandler(Policy<HttpResponseMessage>
.Handle<Exception>()
.CircuitBreakerAsync(10, TimeSpan.FromSeconds(30)));
๐งช Testing & Simulation¶
The generated library includes:
ResiliencyTests.csto simulate failure conditions- Optional mock server support to inject:
- 500, 503, 429 responses
- Timeout conditions
- Header-based retry instructions
๐ Telemetry Hooks¶
All retry/circuit logic is observable:
| Metric | Description |
|---|---|
retry_attempt_count |
Total retries |
circuit_state |
Closed / Open / Half-Open |
timeout_count |
Requests aborted due to timeout |
fallback_used |
Was a fallback strategy applied? |
Emitted via OpenTelemetry or ILogger.
๐ Optional Custom Decorators¶
Blueprint supports:
- Custom retry selector
- Retry per-method granularity
- Fallback method decorators (optional in future blueprint evolution)
โ๏ธ Agents may inject such attributes via code-generation if DSL enables advanced resiliency profiles.
โ Summary¶
The backend API library blueprint ensures production-grade resilience out of the box. With retry policies, circuit breakers, and observability hooks integrated via configuration and agents, every generated client can safely call external systems โ even under partial failure or load spikes.
๐งญ Observability Integration: Logs, Traces, Metrics¶
This section describes how the backend API library blueprint embeds observability hooks โ enabling real-time insights into client behavior, performance bottlenecks, failures, and usage patterns across distributed systems.
๐ Observability Pillars¶
| Pillar | Implementation |
|---|---|
| ๐ Logs | Structured logging via ILogger |
| ๐ Metrics | Built-in counters, histograms, timers |
| ๐ก Tracing | Distributed trace context propagation using OpenTelemetry |
| ๐ง Events | Span events for retries, exceptions, fallbacks |
All are enabled by default, and agents may disable specific pieces via blueprint DSL.
๐ง Blueprint DSL Example¶
๐งฑ Instrumentation Points¶
| Layer | Instrumentation |
|---|---|
| HTTP Pipeline | Request start/end logs, error logs, retry logs |
| Retry Middleware | Emits retry count, result state |
| Circuit Breaker | Logs state transitions (open/close), failure reasons |
| Client Interface | Trace spans per method |
| Authentication | Token fetch timing, cache hits/misses |
๐ Logging Format (Serilog / ILogger)¶
{
"timestamp": "2025-06-07T14:35:21Z",
"message": "StripeClient.GetInvoiceAsync executed",
"httpMethod": "GET",
"url": "https://api.stripe.com/v1/invoices/inv_123",
"durationMs": 482,
"statusCode": 200,
"retryAttempts": 1,
"traceId": "b3943c2...c71"
}
Logs include:
- Correlation IDs
- Span IDs
- Retry/circuit state
- User/tenant context if available
๐ก OpenTelemetry Tracing¶
Every client method is wrapped in:
With trace context passed via:
HttpRequestMessage.Headers- B3, W3C Trace Context, or custom format
Spans are exported to:
- Jaeger
- Zipkin
- Azure Monitor
- Prometheus (via
otel-collector)
๐ Metrics Emitted¶
| Metric Name | Type | Purpose |
|---|---|---|
http_request_duration_seconds |
Histogram | API latency |
retry_attempt_count |
Counter | Retry operations |
client_failure_count |
Counter | Failures grouped by status |
circuit_state |
Gauge | Current CB state (0=closed, 1=open) |
๐งช Test Verification¶
The blueprint includes tests to validate:
- Logs are emitted
- Spans are created
- Metrics counters increment correctly
Can be run with mock tracing and log collectors in CI.
๐ง Agent Skills Used¶
| Agent | Skills |
|---|---|
ObservabilityAgent |
TelemetryHookInjectorSkill, SpanTemplateGeneratorSkill |
TestAgent |
ObservabilityAssertionsSkill, MetricsValidationSkill |
โ Summary¶
Observability in this blueprint is first-class โ not a plugin. Logs, metrics, and traces are automatically injected into every generated client, ensuring every interaction with remote services is measurable, debuggable, and traceable across the ConnectSoft platform.
๐งญ Configuration Binding and Multi-Environment Support¶
This section details how the backend API library blueprint enables configuration flexibility across environments by generating standardized IOptions<T> bindings, support for secret injection, and runtime switching logic โ essential for tenant-aware, secure, and portable deployments.
๐ง Blueprint DSL Configuration Section¶
๐งฉ Generated Options Class¶
public class StripeOptions
{
public string BaseUrl { get; set; }
public string ApiKey { get; set; }
public bool UseSandbox { get; set; }
}
โ๏ธ Configuration Binding Setup¶
Generated extension method:
The client is bound as:
services.AddHttpClient<IStripeClient, StripeClient>()
.ConfigureHttpClient((sp, client) =>
{
var options = sp.GetRequiredService<IOptions<StripeOptions>>().Value;
client.BaseAddress = new Uri(options.BaseUrl);
client.DefaultRequestHeaders.Authorization =
new AuthenticationHeaderValue("Bearer", options.ApiKey);
});
๐ Environment-Specific Configuration Files¶
| File | Use |
|---|---|
appsettings.Development.json |
Local or mock servers |
appsettings.Production.json |
Real service endpoints |
appsettings.Test.json |
CI test stubs |
// appsettings.Production.json
{
"Stripe": {
"BaseUrl": "https://api.stripe.com/v1",
"ApiKey": "__from_keyvault__"
}
}
๐ KeyVault bindings are auto-injected via configuration providers.
๐ Environment-Sensitive Behaviors¶
| Feature | Use Case |
|---|---|
Mock server in Development |
Simulated API test double |
Rate limiting disabled in Staging |
Easier QA throughput |
Strict timeout in Production |
Prevents runaway retries |
| Logging verbosity adjusted | More verbose in Debug, errors only in Prod |
๐ง Optional Bindings¶
The blueprint allows mapping other sections via:
Supports deep navigation, prefix aliasing, and custom
IConfigurationSectionlogic.
๐ Secrets Management Integration¶
Supports secrets loaded from:
Azure Key Vault(viaDefaultAzureCredential).usersecretsEnvironment VariablesCI/CD Variable Groups
๐ Keys like ApiKey, ClientSecret, and TenantId are never hardcoded.
๐ง Generated Metadata¶
The blueprint emits:
{
"config": {
"boundOptions": "StripeOptions",
"section": "Stripe",
"environmentSupport": ["Development", "Staging", "Production"]
}
}
โ Summary¶
Every backend API library generated from this blueprint includes robust configuration scaffolding โ environment-aware, options-bound, and secret-ready. This makes the client safe, portable, and CI/CD-friendly, whether running locally, in tests, or across cloud environments.
๐งญ Unit, Integration, and Contract Testing Strategy¶
This section outlines the testing strategy built into the blueprint โ ensuring that generated backend API libraries are verifiable through unit tests, integration tests (real and simulated), and contract tests aligned with observability and authentication expectations.
๐ฌ Testing Layers Generated¶
| Layer | Type | Purpose |
|---|---|---|
| ๐งช Unit Tests | Pure C# logic (e.g., auth header, DTO validation) | Fast feedback |
| ๐ Integration Tests | Live or mock endpoint invocations | End-to-end behavior |
| ๐ Contract Tests | Validates client matches OpenAPI or expected response structure | Ensures schema sync |
| ๐ Security Tests | Verifies token injection, permission failures | Boundary enforcement |
๐ Test Project Layout¶
/tests/
GoogleAnalyticsClient.Tests/
- StripeClientTests.cs
- StripeAuthTests.cs
- StripeResiliencyTests.cs
- StripeMockServerFixture.cs
โ๏ธ Test Frameworks¶
- ๐งช
MSTest(default) orxUnit, depending on template variant - ๐ค
MockHttpMessageHandlerfor simulating HTTP flows - ๐งฑ
TestServerorWireMock.Netfor full protocol simulation - ๐
IOptionsSnapshot<T>+ test-specific DI configuration
๐ง Agent-Initiated Test Generation¶
Agents generate tests from:
- DSL (
retryPolicy,auth,metricsโshould retry on 503) - Sample payloads
- MockServer DSL
- Usage examples (e.g., from API docs)
Example auto-generated test case:
[TestMethod]
public async Task GetInvoice_ShouldRetryOn503()
{
var mock = new MockHttpMessageHandler();
mock.Expect("/invoices/inv_123")
.Respond(HttpStatusCode.ServiceUnavailable);
mock.Expect("/invoices/inv_123")
.Respond(HttpStatusCode.OK, "application/json", "{...}");
var client = new StripeClient(mock.ToHttpClient());
var result = await client.GetInvoiceAsync("inv_123");
Assert.IsNotNull(result);
mock.VerifyNoOutstandingExpectation();
}
๐ค Contract Testing Option¶
When OpenAPI spec is known or imported:
-
Contract tests validate:
-
DTOs match response schema
- Required fields present
- HTTP methods and paths align
Tooling includes:
NSwagorOpenAPI.NETWireMockwith schema stubbing
๐ Telemetry Assertions¶
The blueprint injects test helpers to validate:
- Logs emitted
- Spans created
- Retry metrics increased
AssertMetric("retry_attempt_count", expected: 2);
AssertSpan("StripeClient.CreateInvoice", status: SpanStatus.Ok);
๐งช Test Modes per Environment¶
| Mode | Description |
|---|---|
Test |
Fast, mock-based |
Staging |
Live endpoint tests (optional pipeline trigger) |
CI |
Replays integration with local test server |
Chaos |
(future) Inject failure conditions via chaos agent |
โ Summary¶
The blueprint ensures every generated backend API library includes a complete testing stack โ not only validating logic correctness, but also verifying telemetry, configuration, retries, and contracts. This improves confidence, security, and compliance in every service that consumes these libraries.
๐งญ Mock Server and Sandbox Generation Support¶
This section covers how the backend API library blueprint generates a mock server alongside the client library. This mock server acts as a sandboxed test double for local development, CI testing, AI agent self-call simulations, and contract validation โ without needing real API access.
๐งช Purpose of the Mock Server¶
| Use Case | Description |
|---|---|
| ๐งช Local Testing | Simulates API responses for integration tests and debugging |
| ๐ง Agent Sandbox | Allows AI agents to test calls without external dependencies |
| โ CI Pipelines | Reliable test runs with no 3rd-party failures |
| ๐ Contract Testing | Validate generated client conforms to expected structure |
| ๐งฑ Multi-tenant Simulation | Emulate different environments or tenants |
๐๏ธ Folder Structure¶
/src/
GoogleAnalyticsClient.MockServer/
Controllers/
Fixtures/
Extensions/
GoogleAnalyticsClient.MockServer.csproj
โ๏ธ Features of the Mock Server¶
| Feature | Description |
|---|---|
| โ Route matching | Handles all client interface methods |
| ๐งช Predefined fixtures | Static or templated JSON files for repeatable outputs |
| ๐ Delay simulation | Artificial latency, timeouts for resiliency tests |
| ๐ Behavior switching | Return 200, 404, 503, or malformed responses |
| ๐ Token check | Can optionally validate API keys, tokens |
| ๐ง AI sandbox hooks | Allows agent-triggered overrides of behavior |
๐งฉ Configuration Example¶
app.MapGet("/customers/{id}", (string id) =>
{
return Results.Ok(new { id, name = "Test Customer", email = "test@connectsoft.ai" });
});
Or dynamically from fixture:
app.MapPost("/invoices", async (HttpContext ctx) =>
{
var json = await File.ReadAllTextAsync("Fixtures/CreateInvoice.json");
return Results.Json(JsonSerializer.Deserialize<object>(json)!);
});
๐ Fixture File Example¶
๐ง Agent Interaction¶
Agents like TestGeneratorAgent or RuntimeSimAgent can:
- Launch the mock server in isolated mode
- Inject temporary fixtures or behaviors via DSL
- Validate outputs from the mock during replay
- Record conversation for feedback loops
๐ง CLI Launch in Local Dev¶
Also used by CI with environment variable
USE_MOCK_SERVER=true
๐ CI Integration¶
- Runs in background process during test stage
-
Used for:
-
Contract validation
- Resiliency testing
- Retry simulation
๐ง DSL Control for Mock Mode¶
This allows the agent to simulate degraded or edge scenarios.
โ Summary¶
Mock server generation is a first-class citizen in the backend API library blueprint. It enables agentic development, repeatable testing, and safer deployments โ giving AI agents and human developers a controllable, realistic sandbox to test and iterate without risk.
๐งญ Pipeline, Packaging, and NuGet Publication Blueprinting¶
This section defines how the backend API library blueprint includes automated DevOps pipeline scaffolding, packaging conventions, and NuGet publication setup. These make the library consumable across microservices, platforms, and other agents with minimal manual steps.
๐งช CI/CD Pipeline Objectives¶
| Goal | Achieved by |
|---|---|
| โ Build validation | .NET build, test, lint stages |
| โ Test automation | Unit, integration, contract test runs |
| ๐ฆ NuGet packaging | dotnet pack with versioning rules |
| ๐ Secure publishing | Push to internal or public NuGet feeds |
| ๐ Blueprint traceability | Artifact tagging with run/session metadata |
๐ File Structure¶
/azure-pipelines.yml
/.factory/publish.meta.json
/src/GoogleAnalyticsClient/
- GoogleAnalyticsClient.csproj
โ๏ธ Generated Azure Pipelines File¶
trigger:
branches:
include: [ main ]
pool:
vmImage: 'windows-latest'
variables:
buildConfiguration: 'Release'
steps:
- task: UseDotNet@2
inputs:
packageType: 'sdk'
version: '8.x'
- script: dotnet restore
- script: dotnet build --configuration $(buildConfiguration)
- script: dotnet test --configuration $(buildConfiguration) --logger trx
- script: dotnet pack --configuration $(buildConfiguration) -o $(Build.ArtifactStagingDirectory)
- task: PublishBuildArtifacts@1
- task: NuGetCommand@2
inputs:
command: 'push'
packagesToPush: '$(Build.ArtifactStagingDirectory)/*.nupkg'
nuGetFeedType: 'internal'
publishVstsFeed: 'connectsoft-nuget-feed-id'
๐ฆ NuGet Metadata Blueprint¶
<PropertyGroup>
<PackageId>ConnectSoft.StripeClient</PackageId>
<Version>1.2.4</Version>
<Authors>ConnectSoft AI Factory</Authors>
<Description>Typed API client for Stripe integration</Description>
<RepositoryUrl>https://dev.azure.com/connectsoft/_git/StripeClient</RepositoryUrl>
</PropertyGroup>
๐ Secure Feed Publishing¶
| Mode | Strategy |
|---|---|
| Internal | Azure Artifacts feed with vstsFeed |
| Public | NuGet.org with API key secret |
| Scoped | Publish to tenant-specific feeds via agent parameter injection |
๐ง Agent Collaboration¶
| Agent | Role |
|---|---|
PipelineAgent |
Generates and validates azure-pipelines.yml |
PackageVersioningAgent |
Bumps version, edits .csproj and meta |
ArtifactRegistryAgent |
Pushes to configured NuGet feeds |
AuditTrailAgent |
Adds session ID to artifact metadata |
๐ Versioning Rules¶
- Patch: Minor edits or bugfixes
- Minor: New methods or endpoints added
- Major: Breaking change in client interface
- Blueprint version stored in
.factory/version.json
Supports SemVer and metadata like:
{
"version": "1.3.0-beta+build123",
"originatingAgent": "LibraryScaffolderAgent",
"timestamp": "2025-06-07T18:32Z"
}
๐งช Publish Validation¶
Blueprint includes test pipeline that:
- Asserts
nupkgstructure - Validates README is present
- Ensures dependency versions match factory policies
โ Summary¶
The blueprint doesnโt just generate code โ it generates a DevOps-ready, publishable library complete with pipeline, semantic versioning, and NuGet configuration. This makes integration, reuse, and CI/CD automation effortless for both agents and human developers.
๐งญ Cross-Agent Consumption and Agent-to-Agent Contracts¶
This section explains how the generated backend API library can be safely and programmatically consumed by other agents within the ConnectSoft AI Software Factory โ enabling agent-to-agent contracts, intelligent orchestration, and multi-agent workflows using shared, versioned SDKs.
๐ค Why Agent-to-Agent Contracts Matter¶
| Benefit | Description |
|---|---|
| โ Consistency | All agents use the same SDK interfaces and models |
| โ Decoupling | Interface hides low-level HTTP complexity |
| ๐ง Reasoning | Agents reason over clear method signatures |
| ๐ Reusability | Reuse library across design-time and runtime agents |
| ๐ Trust | Versioned contract prevents breaking changes |
๐ง Agent Usage Examples¶
| Consumer Agent | Purpose |
|---|---|
TestOrchestratorAgent |
Calls generated mock server using IStripeClient |
RuntimeSimAgent |
Executes sample flow to validate expected results |
MCP Integration Agent |
Binds external skill to generated library methods |
ValidationAgent |
Verifies library behavior against blueprint DSL |
CodeReviewerAgent |
Analyzes interface for DDD and traceability standards |
๐งฉ Agent DSL Output Example¶
useLibrary: ConnectSoft.StripeClient
methods:
- name: CreateInvoiceAsync
input: CreateInvoiceRequest
output: InvoiceResponse
requiredHeaders: [ Authorization ]
retryable: true
observable: true
This DSL is generated alongside the blueprint and used as input to agentic chains.
โ๏ธ AI Usage (in SK Plugins)¶
When exposed to Semantic Kernel agents:
[KernelFunction]
public async Task<InvoiceResponse> CreateStripeInvoiceAsync(string customerId)
{
return await _stripeClient.CreateInvoiceAsync(new CreateInvoiceRequest
{
CustomerId = customerId,
AutoAdvance = true
});
}
โ The generated interface becomes a plug-and-play skill in the kernel function system, enabling hybrid agent + OpenAI workflows.
๐งฑ Contract Metadata (.factory/agent.contract.json)¶
{
"interface": "IStripeClient",
"methods": [
{
"name": "CreateInvoiceAsync",
"inputs": ["customerId", "amount"],
"output": "InvoiceResponse",
"auth": "apiKey"
}
],
"origin": "agent-blueprint-run-02458"
}
Agents fetch this metadata to dynamically inspect capabilities and emit calls.
๐งช Contract-Driven Validation¶
Contract metadata is used for:
- Auto-prompt generation
- Request replay testing
- Failure path simulation
- Version mismatch detection (if consumer requires a method not found in current version)
๐ค Example Multi-Agent Chain¶
sequenceDiagram
DevAgent ->> BlueprintAgent: Request Stripe API library
BlueprintAgent ->> CodeAgent: Generate client
CodeAgent ->> PackageAgent: Push NuGet
RuntimeAgent ->> NuGet: Install ConnectSoft.StripeClient
RuntimeAgent ->> StripeClient: CreateInvoiceAsync()
๐ฆ One library, many consumers: orchestrators, validators, SK agents, DevOps agents, and runtime clusters.
โ Summary¶
The backend API library blueprint produces artifacts that are not just code โ they are agent-readable, memory-indexed, skill-convertible contracts. This enables deep reuse across the entire agentic lifecycle and reinforces composability, observability, and automation at platform scale.
๐งญ Memory, Metadata, and Traceability in Blueprint Artifacts¶
This section explores how every generated backend API library embeds traceable metadata and integrates into the platform's memory system โ enabling full observability, lookup, and auditability for every artifact produced by the AI Software Factory.
๐ง Why Memory & Metadata Matter¶
| Capability | Purpose |
|---|---|
| ๐งญ Traceability | Understand what agent produced what artifact, from which prompt |
| ๐ Replayability | Rebuild any artifact from blueprint and memory |
| ๐ง Context Awareness | Other agents can search for and reason over prior blueprints |
| ๐งช Provenance | Verify trust chain of generated code |
| ๐ฆ Reuse | Compose new solutions using prior libraries as base packages |
๐ Metadata Files Injected into Output¶
| File | Purpose |
|---|---|
.factory/blueprint.meta.json |
Blueprint ID, version, inputs, producers |
.factory/agent.contract.json |
Machine-readable method + parameter contract |
.factory/memory.tags.yaml |
Vector DB tags (domain, purpose, API group) |
README.md (with prompt header) |
Human-readable trace of what was generated and why |
๐งฌ Sample blueprint.meta.json¶
{
"blueprintId": "backend.api.library",
"name": "ConnectSoft.StripeClient",
"producedByAgent": "LibraryScaffolderAgent",
"version": "1.0.0",
"timestamp": "2025-06-07T22:00:15Z",
"sourceInputs": [
"https://api.stripe.com/v1",
"OpenAPI spec",
"custom DSL"
],
"linkedBlueprints": [
"observability.default",
"configuration.standard"
],
"memoryIndex": "agentic-blueprints/backend.api.library/stripeclient"
}
๐ Memory Tagging (Vector Indexing)¶
The blueprint includes a memory.tags.yaml file:
tags:
domain: "Billing"
system: "Stripe"
type: "backend.api.library"
methodProfiles:
- create_invoice
- get_customer
observability: true
retryable: true
This is embedded into the memory ingestion pipeline, enabling:
- Searchable lookup from any agent
- Memory recall in downstream factories
- Cross-blueprint reasoning (e.g., infer capabilities)
๐ง Embedding Strategy¶
- Interface signatures, model class names, method names โ embedded into vector DB
- Token metadata (e.g., HTTP verbs, paths, common errors) โ embedded for contract memory
- Blueprint DSL fragments โ embedded to power reuse and validation prompts
Stored in vector collections:
blueprints/backend.api.libraryclients/http.methodsskills/generated-by-agent
๐ Traceability Hooks¶
Agents can answer:
- "Which agent generated this client?"
- "When was this client last updated?"
- "What API spec was this client based on?"
- "Does a library for service X already exist?"
๐ง Used by Other Agents¶
| Agent | Use |
|---|---|
KnowledgeAgent |
Lookup previously generated libraries |
ReuseOrchestratorAgent |
Reuses existing blueprints via vector similarity |
RegenerationAgent |
Rebuilds broken artifacts from prompt + metadata |
AuditAgent |
Validates contract compliance across versions |
โ Summary¶
This blueprint doesnโt just generate clients โ it emits memory-aware, self-describing artifacts. With structured metadata, memory tagging, and embedding support, every library becomes a first-class citizen in the AI Software Factoryโs collective intelligence.
๐งญ Error Handling, Fallbacks, and Developer Feedback Features¶
This section describes how the backend API library blueprint integrates structured error handling, optional fallback strategies, and tooling for developers and agents to analyze, log, and respond to failures in predictable and traceable ways.
๐ฅ Error Types Handled¶
| Type | Examples | Handling Strategy |
|---|---|---|
| HTTP Errors | 4xx, 5xx, 429 | Standardized exception + retry logic |
| Transport Failures | DNS, Timeout, ConnectionRefused | Retry + circuit breaker |
| Deserialization Errors | Invalid/missing fields | Safe fallback or developer trace |
| Auth Failures | 401, 403 | Token refresh or prompt user |
| Rate Limits | 429 + Retry-After |
Observes backoff policy |
๐งฑ Unified Error Model¶
Generated libraries use a common exception hierarchy:
public class ApiException : Exception
{
public HttpStatusCode StatusCode { get; }
public string? ResponseBody { get; }
public string? Endpoint { get; }
public ApiException(string message, HttpStatusCode statusCode, string? responseBody = null)
: base(message) { ... }
}
public class AuthException : ApiException { ... }
public class DeserializationException : ApiException { ... }
public class RetryExhaustedException : ApiException { ... }
๐งช Developer-Visible Feedback¶
All failures are logged with:
- Request URL, headers (sanitized)
- Status code and error body
- Retry attempts
- TraceId / CorrelationId
Example log:
{
"level": "Error",
"message": "Failed to fetch invoice inv_123",
"statusCode": 503,
"retries": 3,
"endpoint": "/invoices/inv_123",
"traceId": "e293..."
}
๐ Optional Fallback Strategies¶
Defined in DSL or injected later:
OR in generated code (future support):
[FallbackResponse(typeof(InvoiceResponse), Source = "json", Path = "fallbacks/invoice.json")]
Task<InvoiceResponse> GetInvoiceAsync(string invoiceId);
๐ง Agent-Driven Error Handling¶
| Agent | Role |
|---|---|
TestAgent |
Validates retry, timeout, error boundaries |
ObservabilityAgent |
Emits spans with failure markers |
RuntimeSimAgent |
Verifies fallback pathways |
DocsAgent |
Generates "how to handle this error" sections |
๐ Error Documentation Blueprint¶
Part of the README and .factory/errors.json:
{
"operation": "CreateInvoiceAsync",
"errors": [
{ "code": 401, "meaning": "Invalid API Key", "suggestion": "Check StripeOptions.ApiKey" },
{ "code": 429, "meaning": "Rate Limit", "suggestion": "Back off and retry after delay" }
]
}
๐ Integration with Observability¶
Each error emits:
- ๐ชต
ILogger.LogErrorwith detailed context - ๐ Metrics like
client_error_count{code=503} - ๐ก Tracing span with status code and failure tag
This makes failure rates and retry loops fully observable.
โ Summary¶
Robust, structured error handling is a core pillar of the backend API blueprint. From retry-aware exceptions to agent-visible logs and fallback JSON, every failure becomes an opportunity for recovery, traceability, and continuous improvement across automated and manual consumers.
๐งญ Versioning, Deprecation, and Backward Compatibility Strategies¶
This section outlines how the backend API library blueprint implements semantic versioning, deprecation signaling, and backward compatibility enforcement across generated artifacts โ ensuring stability, safe upgrades, and contract integrity across consuming services and agents.
๐งฎ Versioning Model¶
| Component | Rule |
|---|---|
| ๐ฆ NuGet Package | Uses SemVer 2.0.0 |
| ๐ง Blueprint Version | Embedded in metadata (blueprint.meta.json) |
| ๐งพ Contract Hash | Used for backward compatibility checks |
| ๐ Source Tag | Git tag/version injected into project README and changelog |
Example:
{
"packageVersion": "1.3.2",
"blueprintVersion": "v2",
"apiContractHash": "cfb294e3...",
"generatedBy": "agent-blueprint-run-05923"
}
๐งช Change Detection Heuristics¶
Agents or the pipeline detect:
| Change | Impact |
|---|---|
| New method added | Minor bump |
| Existing method removed | Major bump |
| Input/output changed | Major bump |
| Retry policy tweaked | Patch |
| Logging format changed | Patch (internal) |
Detected via:
- Interface diffs (AST or Roslyn analysis)
- OpenAPI diff (when spec-based)
- Contract hash comparison
โ ๏ธ Deprecation Mechanism¶
Deprecation is encoded in both metadata and source code:
[Obsolete("Use CreateInvoiceV2Async instead.")]
public Task<InvoiceResponse> CreateInvoiceAsync(...) { ... }
And reflected in:
{
"operation": "CreateInvoiceAsync",
"status": "deprecated",
"replacement": "CreateInvoiceV2Async"
}
๐ง Agents see this and auto-adjust their flows.
๐ Changelog Generation¶
Agents generate a changelog:
## v1.4.0
- Added: `SendNotificationAsync` method
- Changed: `RetryPolicy` now exponential backoff by default
- Deprecated: `SendEmailAsync` (use `SendNotificationAsync`)
Stored in CHANGELOG.md and .factory/changelog.md.
๐ง Consumers React to Versions¶
| Agent | Behavior |
|---|---|
CodeReviewerAgent |
Flags major change without test coverage |
UpdateAssistantAgent |
Suggests upgrade path for affected consumers |
RuntimeValidatorAgent |
Warns if deprecated method is still used |
BuildPinnerAgent |
Locks to safe version range (e.g., <2.0.0) |
๐ Support for Multiple Versions¶
The factory allows:
- Side-by-side packaging (
MyClient.V1,MyClient.V2) - Adapter classes or shims
- Graceful opt-in to new interface with compatibility toggle
๐งช Version Tests (Optional)¶
Generated tests ensure older methods are still callable (if supported):
[TestMethod]
public void DeprecatedMethod_StillCompilesAndRuns()
{
var client = new StripeClient(...);
var invoice = client.CreateInvoiceAsync("cus_123").Result;
Assert.IsNotNull(invoice);
}
โ Summary¶
Versioning in the backend API library blueprint is not just syntactic โ itโs semantic, agent-visible, and upgrade-aware. With embedded changelogs, deprecation notices, and behavioral diffing, this blueprint ensures stable evolution and safe reuse across generations of software and automation agents.
๐งญ Runtime Extension Points and Composition Hooks¶
This section explains how the backend API library blueprint enables safe extensibility and runtime customization through generated extension points, partial methods, composition hooks, and plugin-ready structures โ all while preserving stability, testability, and compatibility.
๐งฉ Why Extension Points Matter¶
| Need | Solution |
|---|---|
| ๐ Add custom headers or transformations | Request/response interceptors |
| ๐ง Inject observability hooks | Span decorators |
| ๐งช Override retry/fallback logic | Pluggable policies |
| ๐ Replace endpoint behavior | Partial method stubs |
| ๐ฆ Plug in external libraries | DI composition modules |
๐งฑ Composition Hook Locations¶
| Hook | Purpose |
|---|---|
HttpRequestMessageBuilder |
Modify request before send |
IResponseParser |
Customize deserialization and validation |
AuthHandler |
Token injection, renewal |
ILoggerDecorator |
Extend observability span |
ErrorClassifier |
Wrap specific HTTP responses into typed exceptions |
These hooks are injected via DI or method override stubs.
๐ง Example: Request Customizer Hook¶
Injected into the client:
Allows agent or developer to:
- Add tenant ID
- Inject trace headers
- Modify URL dynamically
๐งฉ Partial Method for Override¶
public partial class StripeClient
{
partial void OnBeforeSend(HttpRequestMessage request);
partial void OnAfterReceive(HttpResponseMessage response);
}
These methods are no-ops unless implemented. Safe for extension in shared libraries.
๐ฆ Generated Extension Points in DI¶
services.AddTransient<IRequestCustomizer, CustomHeaderInjector>();
services.AddScoped<IResponseParser, CustomParser>();
Or configured via factory:
.AddHttpClient<IStripeClient, StripeClient>((sp, client) => {
var auth = sp.GetRequiredService<IAccessTokenProvider>();
client.DefaultRequestHeaders.Authorization = new(...);
});
๐ Agent-Powered Composition¶
Agents can:
- Extend generated classes using
partialfiles - Register new behaviors via metadata DSL:
extensions:
requestHeaderInjector:
enabled: true
header: "X-Tenant-ID"
source: "ContextResolverService"
- Inject handlers during orchestration or test setup
- Publish customized libraries as variants
๐ค Inter-Agent Hooks¶
Some extensions are targeted at other agent types, e.g.:
- Observability spans injected by
ObservabilityAgent - Tracing headers managed by
RequestTracerAgent - Error classifiers aligned with
ContractValidatorAgent
This enables safe chaining across platform clusters.
โ๏ธ Extension Strategy: Open/Closed Principle¶
- Open: via interfaces, delegates, DI hooks
- Closed: core retry/auth policies guarded by factory
- Overrides must be opt-in via DSL or agent contract extension
โ Summary¶
Every backend API client generated from this blueprint includes safe and composable runtime hooks. Developers and agents can extend behavior without modifying core logic, ensuring platform integrity while enabling rich cross-agent composition and specialization.
๐งญ Blueprint-Driven Documentation and Developer Portal Integration¶
This section details how the blueprint generates structured documentation artifacts for developer consumption, agent reasoning, and integration into internal and external developer portals, ensuring the client library is understandable, traceable, and self-describing.
๐ Types of Documentation Generated¶
| Format | Purpose |
|---|---|
README.md |
Entry-point doc with usage examples |
docs/ Markdown |
Advanced usage, config, testing, security |
.factory/errors.json |
Structured error reference |
.factory/agent.contract.json |
Agent-readable method and type schema |
CHANGELOG.md |
Human + agent trace of evolution |
docs/openapi.json (optional) |
If derived from OpenAPI or Swagger spec |
๐ Folder Structure¶
/docs/
README.md
usage.md
configuration.md
troubleshooting.md
authentication.md
testing.md
changelog.md
.factory/
agent.contract.json
errors.json
๐ README.md Sample¶
# ConnectSoft.StripeClient
This library provides a typed API interface to Stripe for use within ConnectSoft services and AI agents.
## ๐ Usage
```csharp
var result = await _stripeClient.CreateInvoiceAsync(new() {
CustomerId = "cus_abc123",
AutoAdvance = true
});
```
## ๐ฆ Configuration
Bind options from `Stripe` section in `appsettings.json`.
## ๐ Retry
The client retries 3 times on 429, 503, and timeout errors.
๐ Regeneration and Update Hooks¶
Documentation is versioned and regenerated automatically when:
- Methods change
- Retry/auth/fallback policies are added or removed
- Blueprint version or contract hash is updated
Ensures drift between code and docs is minimized.
๐ง Agent-Readable Contracts¶
{
"methods": [
{
"name": "CreateInvoiceAsync",
"parameters": ["CustomerId", "AutoAdvance"],
"output": "InvoiceResponse",
"auth": true,
"retryable": true
}
],
"errorModel": "ApiException",
"observable": true
}
````
Used by:
* `CodeReviewerAgent`
* `RuntimeTestAgent`
* `PromptOrchestratorAgent`
---
### ๐ Developer Portal Integration
| Portal | Integration |
| ---------------------- | ------------------------------------------------------- |
| ConnectSoft DevCenter | Indexed into internal portal registry |
| AI Blueprint Browser | Searchable via memory and blueprint viewer |
| Public Docs (optional) | Exportable to Markdown, OpenAPI, or doc-as-code formats |
| ChatGPT Plugin Builder | SDK + method hints injected via prompt metadata |
Blueprint emits:
* Tags for search
* Links to changelog, README, test coverage
* Downloadable package metadata
---
### ๐ง Developer Feedback Loops
Future versions may include:
* Embedded "copy this usage" button
* Error codes โ help article mapping
* Interactive client playground using mock server
* Agent-published usage patterns and hints
---
### โ
Summary
Documentation is a **first-class output** of the blueprint โ not an afterthought. Itโs human-friendly, agent-readable, portal-integrated, and change-aware. This ensures maximum clarity, adoption, and platform alignment across all developer and AI agent consumers.
---
## ๐งญ Blueprint-Driven Compliance, Auditability, and Policy Alignment
This final section covers how the backend API library blueprint enforces **compliance with organizational policies**, emits **audit metadata**, and aligns with **security, observability, and quality requirements** across all generated libraries โ ensuring trust, accountability, and governance at scale.
---
### ๐ Compliance Domains Addressed
| Domain | Compliance Strategy |
| ----------------- | ------------------------------------------------------- |
| ๐ Security | Token usage, sensitive field masking, TLS-only clients |
| ๐ Observability | Span creation, error telemetry, retry logging |
| ๐ Retry Policies | Blueprint-based backoff settings, retry limits |
| ๐ฆ Packaging | Naming conventions, license headers, artifact structure |
| โ๏ธ Licensing | Default MIT/ConnectSoft license headers with validation |
| ๐ Documentation | Required sections and changelog generation |
| ๐ค Data Privacy | Field-level PII masking and logging policies |
---
### ๐ Policy Rules Enforced by Blueprint
| Rule | Enforced By |
| ------------------------------------------------------------- | --------------- |
| All HTTP clients must use `ILogger` and structured logs | Template |
| Retryable methods must expose `RetryPolicyOptions` | DSL constraint |
| Public-facing packages must contain `README.md` and `LICENSE` | Linter |
| `ApiKey` must be sourced from `IOptions` or `KeyVault` only | Generator guard |
| DTO fields with PII tags are auto-masked in logs | Serializer shim |
| All exceptions must extend `ApiException` | Validator agent |
---
### ๐ Audit Files and Metadata
| File | Purpose |
| ----------------------------- | ---------------------------------------------- |
| `.factory/audit.json` | Agent trail, session IDs, prompt hashes |
| `README.md` header | Includes creation origin and blueprint version |
| `changelog.md` | Shows code changes across blueprint runs |
| `.factory/policy.report.json` | Which policies were enforced or bypassed |
Example `.factory/audit.json`:
```json
{
"generatedBy": "LibraryScaffolderAgent",
"sessionId": "run-2321312",
"promptFingerprint": "8a9cb0f8...",
"blueprintVersion": "v2.3",
"policyCompliance": ["auth.tokens.secured", "observability.traces.emitted"],
"timestamp": "2025-06-07T23:45:02Z"
}
๐ง Agent Alignment¶
| Agent | Use |
|---|---|
PolicyValidatorAgent |
Validates blueprint output against factory rules |
SecurityScannerAgent |
Reviews token handling and URL injection safety |
AuditTrailAgent |
Records generator identity and session for each artifact |
DocumentationAgent |
Injects policy reference into public docs |
ContractValidatorAgent |
Asserts backward compatibility against contract hash |
๐ Blueprint Policy Profiles¶
The blueprint can inject policy levels:
compliance:
profile: strict
rules:
- auth.tokens.required
- observability.enabled
- retry.policy.defined
- changelog.required
These policies become binding for the agent execution context.
๐ Security Hooks¶
- HTTP clients require TLS or fail-fast
- Authorization header redacted from all logs
- Request tracing headers (e.g.
X-Correlation-ID) injected by default - Access tokens must be non-null or throw
๐ Audit Chain Traceability¶
Mermaid view:
flowchart TD
A[LibraryScaffolderAgent] --> B[BlueprintEmitter]
B --> C[.factory/blueprint.meta.json]
B --> D[.factory/audit.json]
B --> E[NuGet Package]
E --> F[AgentOrRuntimeConsumer]
Every artifact is cryptographically and semantically linked back to its origin.
โ Summary¶
This final layer of the backend API library blueprint enforces a trustworthy, compliant, auditable software generation process. With metadata trails, enforcement hooks, and policy-aligned generation, ConnectSoft ensures that every output โ even from AI agents โ meets enterprise standards and regulatory needs.