diff --git a/src/FiscalOS.API/Accounts/Connect/Endpoint.cs b/src/FiscalOS.API/Accounts/Connect/Endpoint.cs
index 2ec2ba5..1085541 100644
--- a/src/FiscalOS.API/Accounts/Connect/Endpoint.cs
+++ b/src/FiscalOS.API/Accounts/Connect/Endpoint.cs
@@ -9,7 +9,9 @@ internal static class Endpoint
     return groupBuilder.MapPost(Route, HandleAsync);
   }
 
-  private static async Task<IResult> HandleAsync()
+  private static async Task<IResult> HandleAsync(
+    [FromBody] Request request
+  )
   {
     return Results.Ok();
   }
diff --git a/src/FiscalOS.API/Accounts/Connect/Request.cs b/src/FiscalOS.API/Accounts/Connect/Request.cs
new file mode 100644
index 0000000..980369a
--- /dev/null
+++ b/src/FiscalOS.API/Accounts/Connect/Request.cs
@@ -0,0 +1,22 @@
+namespace FiscalOS.API.Accounts.Connect;
+
+public record Request : IValidatableObject
+{
+  public string PublicToken { get; init; } = string.Empty;
+  public string PlaidInstitutionId { get; init; } = string.Empty;
+
+  public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
+  {
+    if (string.IsNullOrWhiteSpace(PublicToken))
+    {
+      var fieldName = nameof(PublicToken);
+      yield return new($"The {fieldName} field is required.", [fieldName]);
+    }
+
+    if (string.IsNullOrWhiteSpace(PlaidInstitutionId))
+    {
+      var fieldName = nameof(PlaidInstitutionId);
+      yield return new($"The {fieldName} field is required.", [fieldName]);
+    }
+  }
+}
\ No newline at end of file
diff --git a/tests/FiscalOS.API.Tests/Integration/ConnectTests.cs b/tests/FiscalOS.API.Tests/Integration/ConnectTests.cs
index e017cfd..57b2888 100644
--- a/tests/FiscalOS.API.Tests/Integration/ConnectTests.cs
+++ b/tests/FiscalOS.API.Tests/Integration/ConnectTests.cs
@@ -11,4 +11,73 @@ public class ConnectTests(TestApi testApi) : IntegrationTest(testApi)
 
     await res.Should().BeProblemDetails(HttpStatusCode.Unauthorized);
   }
+
+  [Fact]
+  public async Task Connect_WhenCalledWithoutPublicTokenOrPlaidInstitutionId_ItShouldReturn400WithProblemDetails()
+  {
+    var jwt = JwtTokenBuilder.New()
+      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+      .Build();
+
+    using var content = new StringContent(JsonSerializer.Serialize(new { }), Encoding.UTF8, "application/json");
+    using var request = new HttpRequestMessage(HttpMethod.Post, ConnectUri)
+    {
+      Content = content,
+    };
+    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
+
+    var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
+
+    await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
+    {
+      ["PublicToken"] = ["The PublicToken field is required."],
+      ["PlaidInstitutionId"] = ["The PlaidInstitutionId field is required."],
+    });
+  }
+
+  [Fact]
+  public async Task Connect_WhenCalledWithoutPublicToken_ItShouldReturn400WithProblemDetails()
+  {
+    var jwt = JwtTokenBuilder.New()
+      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+      .Build();
+
+    var json = JsonSerializer.Serialize(new { plaidInstitutionId = "id" });
+    using var content = new StringContent(json, Encoding.UTF8, "application/json");
+    using var request = new HttpRequestMessage(HttpMethod.Post, ConnectUri)
+    {
+      Content = content,
+    };
+    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
+
+    var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
+
+    await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
+    {
+      ["PublicToken"] = ["The PublicToken field is required."],
+    });
+  }
+
+  [Fact]
+  public async Task Connect_WhenCalledWithoutPlaidInstitutionId_ItShouldReturn400WithProblemDetails()
+  {
+    var jwt = JwtTokenBuilder.New()
+      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+      .Build();
+
+    var json = JsonSerializer.Serialize(new { publicToken = "token" });
+    using var content = new StringContent(json, Encoding.UTF8, "application/json");
+    using var request = new HttpRequestMessage(HttpMethod.Post, ConnectUri)
+    {
+      Content = content,
+    };
+    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
+
+    var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
+
+    await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
+    {
+      ["PlaidInstitutionId"] = ["The PlaidInstitutionId field is required."],
+    });
+  }
 }
\ No newline at end of file
diff --git a/tests/FiscalOS.API.Tests/Usings.cs b/tests/FiscalOS.API.Tests/Usings.cs
index d403688..e9f8ff4 100644
--- a/tests/FiscalOS.API.Tests/Usings.cs
+++ b/tests/FiscalOS.API.Tests/Usings.cs
@@ -4,6 +4,8 @@ global using System.Net.Http.Headers;
 global using System.Net.Http.Json;
 global using System.Security.Claims;
 global using System.Security.Cryptography;
+global using System.Text;
+global using System.Text.Json;
 
 global using AwesomeAssertions.Execution;
 global using AwesomeAssertions.Primitives;