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Contract Coverage ​

--check verifies that every contract endpoint has a matching implementation — correct HTTP method, correct route. Catches drift between contracts and controllers before your code ships.

Command ​

bash
# Standalone — exits with code 1 if any warnings
dotnet rivet --project Api.csproj --check --quiet

# Standalone with codegen preview
dotnet rivet --project Api.csproj --check

# Combined with generation — check + generate in one pass
dotnet rivet --project Api.csproj --output ./generated --check

What it detects ​

--check finds every [RivetContract] static class, then looks for .Invoke() call sites on each field. For each call site, it resolves the HTTP method and route from the surrounding context and compares against the contract.

Missing implementation ​

A contract field with no .Invoke() call anywhere in the project:

warning: [MissingImplementation] MembersContract.UpdateRole: expected PUT /api/members/{id}/role, got (none)

HTTP method mismatch ​

The contract says GET, but the controller or minimal API endpoint uses POST:

csharp
// Contract: Define.Get<List<MemberDto>>("/api/members")
// Controller:
[HttpPost]  // ← wrong
public async Task<IActionResult> List(CancellationToken ct)
    => (await MembersContract.List.Invoke(async () => ...)).ToActionResult();
warning: [HttpMethodMismatch] MembersContract.List: expected GET, got POST

Route mismatch ​

The contract says /api/members but the controller routes to /api/users:

warning: [RouteMismatch] MembersContract.List: expected /api/members, got /api/users

Works with MVC controllers and minimal APIs ​

--check resolves the implementation context by walking up the syntax tree from each .Invoke() call:

MVC controllers — reads [HttpGet], [Route] etc. from the containing method and class:

csharp
[Route("api/members")]
public sealed class MembersController : ControllerBase
{
    [HttpGet]
    public async Task<IActionResult> List(CancellationToken ct)
        => (await MembersContract.List.Invoke(async () => ...)).ToActionResult();
}

Minimal APIs — walks up through the lambda to the MapGet/MapPost/etc. call to extract the HTTP method and route. Use .Route to avoid duplicating the route string:

csharp
app.MapGet(MembersContract.List.Route, async (AppDb db, CancellationToken ct) =>
    (await MembersContract.List.Invoke(async () =>
    {
        return await db.Members.ToListAsync(ct);
    })).ToResult());

Both are checked automatically — no extra configuration needed.

Note: Route validation for minimal APIs only works with literal string routes passed to MapGet/MapPost/etc. If you use .Route from a contract field (e.g., MembersContract.List.Route), only the HTTP method is checked — the route value is a runtime property reference that can't be resolved statically.

CI usage ​

--check without --output exits with code 1 if any warnings are found, making it easy to add to CI. Use --quiet (-q) to suppress codegen preview output:

bash
dotnet rivet --project Api.csproj --check --quiet

Prints a coverage summary to stderr:

Coverage: 79/79 endpoints covered. All OK.

Or with warnings:

warning: [MissingImplementation] MembersContract.UpdateRole: expected PUT /api/members/{id}/role, got (none)
Coverage: 78/79 endpoints covered, 0 mismatch(es), 1 missing.

Combined with --output, warnings are reported but the exit code reflects generation success — the check is advisory.

Scope ​

--check only applies to v1 static class contracts with RouteDefinition fields and .Invoke() calls. It does not check:

  • v2 abstract class contracts (the compiler already enforces signatures via override)
  • [RivetClient] / [RivetEndpoint] annotations (the controller is the source of truth)