Auto-Fix for .NET 10 OpenAPI Source Generator Bugs

Problem Context

Developers using .NET 10 with ASP.NET Core APIs rely on XML documentation to auto-generate OpenAPI/Swagger specs. The new OpenAPI source generator fails when mapping <example> tags to IOpenApiMediaType.Example because Microsoft made the property read-only, breaking builds and documentation.

Pain Points

The error CS0200 stops builds, forcing devs to either disable the generator (losing auto-docs), remove XML examples (losing Swagger examples), or manually patch generated files (error-prone). Workarounds like clean/rebuild only work temporarily and break on code changes.

Impact

This causes wasted dev time (5+ hours/week per team), broken CI/CD pipelines, and missing API documentation—directly impacting API adoption, onboarding, and revenue. Teams either stall .NET 10 upgrades or lose critical Swagger examples for consumers.

Urgency

The problem blocks .NET 10 adoption for API teams and forces manual workarounds that break frequently. Without a fix, teams either stay on older .NET versions or lose auto-generated API docs, which are critical for developer experience and API consumption.

Target Audience

ASP.NET Core API developers, DevOps engineers, and technical leads at companies using .NET 10 who rely on OpenAPI/Swagger for API documentation. This affects teams migrating to .NET 10, as well as those maintaining APIs with XML documentation.

Solution Approach

A NuGet package + CLI tool that automatically patches the generated OpenAPI source code at build time to make IOpenApiMediaType.Example writable, restoring the XML-to-Swagger mapping without requiring code changes or disabling the generator. It works as a post-build step, ensuring API docs generate correctly every time.

Key Features

1. Seamless Integration: Works as a MSBuild target or CLI tool, requiring no changes to existing XML docs or controller code.
2. CI/CD Ready: Can be added to build pipelines to ensure consistent API doc generation across environments.
3. Version-Specific Fixes: Updates for new .NET versions as Microsoft releases them, keeping pace with breaking changes.

User Experience

Developers install the NuGet package, add a single line to their .csproj, and the tool runs automatically after each build. No manual edits to generated files or XML docs are needed. API documentation regenerates correctly, and CI/CD pipelines pass without manual intervention.

Differentiation

Unlike manual workarounds (disabling the generator or removing XML examples), this tool preserves all existing functionality while fixing the root cause. It’s lighter than forking Microsoft’s source generator and more reliable than clean/rebuild hacks. Competitors don’t exist—this is the first tool to patch this specific .NET 10 bug.

Scalability

The tool can scale from small teams to large enterprises by supporting per-repository licensing. Additional features like custom OpenAPI transformations or multi-project builds can be added as paid tiers. Updates for new .NET versions ensure long-term relevance.

Expected Impact

Teams regain lost productivity (no more manual fixes), enable .NET 10 upgrades without breaking docs, and maintain Swagger examples for API consumers. The tool reduces CI/CD failures and ensures consistent API documentation across all environments.