diff --git a/test/core/end2end/BUILD b/test/core/end2end/BUILD
index a88f15aebb1..29cace309e8 100644
--- a/test/core/end2end/BUILD
+++ b/test/core/end2end/BUILD
@@ -25,6 +25,7 @@ grpc_cc_library(
     srcs = ["cq_verifier.cc"],
     hdrs = ["cq_verifier.h"],
     external_deps = [
+        "absl/container:flat_hash_map",
         "absl/functional:any_invocable",
         "absl/strings",
         "absl/strings:str_format",
diff --git a/test/core/end2end/cq_verifier.cc b/test/core/end2end/cq_verifier.cc
index 630f50a71a4..a905c84508b 100644
--- a/test/core/end2end/cq_verifier.cc
+++ b/test/core/end2end/cq_verifier.cc
@@ -269,21 +269,36 @@ std::string CqVerifier::ToShortString() const {
 }
 
 void CqVerifier::FailNoEventReceived(const SourceLocation& location) const {
-  fail_(Failure{location, "No event received", ToStrings()});
+  fail_(Failure{location, "No event received", ToStrings(), {}});
 }
 
 void CqVerifier::FailUnexpectedEvent(grpc_event* ev,
                                      const SourceLocation& location) const {
+  std::vector<std::string> message_details;
+  if (ev->type == GRPC_OP_COMPLETE && ev->success) {
+    auto successful_state_strings = successful_state_strings_.find(ev->tag);
+    if (successful_state_strings != successful_state_strings_.end()) {
+      for (SuccessfulStateString* sss : successful_state_strings->second) {
+        message_details.push_back(sss->GetSuccessfulStateString());
+      }
+    }
+  }
   fail_(Failure{location,
                 absl::StrCat("Unexpected event: ", grpc_event_string(ev)),
-                ToStrings()});
+                ToStrings(), std::move(message_details)});
 }
 
 namespace {
 std::string CrashMessage(const CqVerifier::Failure& failure) {
-  std::string message =
-      absl::StrCat(failure.message, "\nexpectation checked @ ",
-                   failure.location.file(), ":", failure.location.line());
+  std::string message = failure.message;
+  if (!failure.message_details.empty()) {
+    absl::StrAppend(&message, "\nwith:");
+    for (const auto& detail : failure.message_details) {
+      absl::StrAppend(&message, "\n  ", detail);
+    }
+  }
+  absl::StrAppend(&message, "\nchecked @ ", failure.location.file(), ":",
+                  failure.location.line());
   if (!failure.expected.empty()) {
     absl::StrAppend(&message, "\nexpected:\n");
     for (const auto& line : failure.expected) {
@@ -422,4 +437,13 @@ void CqVerifier::Expect(void* tag, ExpectedResult result,
   expectations_.push_back(Expectation{location, tag, std::move(result)});
 }
 
+void CqVerifier::AddSuccessfulStateString(
+    void* tag, SuccessfulStateString* successful_state_string) {
+  successful_state_strings_[tag].push_back(successful_state_string);
+}
+
+void CqVerifier::ClearSuccessfulStateStrings(void* tag) {
+  successful_state_strings_.erase(tag);
+}
+
 }  // namespace grpc_core
diff --git a/test/core/end2end/cq_verifier.h b/test/core/end2end/cq_verifier.h
index 893a7ca0f12..688af924717 100644
--- a/test/core/end2end/cq_verifier.h
+++ b/test/core/end2end/cq_verifier.h
@@ -25,6 +25,7 @@
 #include <string>
 #include <vector>
 
+#include "absl/container/flat_hash_map.h"
 #include "absl/functional/any_invocable.h"
 #include "absl/types/variant.h"
 
@@ -64,10 +65,22 @@ class CqVerifier {
   using ExpectedResult =
       absl::variant<bool, Maybe, AnyStatus, PerformAction, MaybePerformAction>;
 
+  // Captures information about one failure
   struct Failure {
     SourceLocation location;
     std::string message;
     std::vector<std::string> expected;
+    std::vector<std::string> message_details;
+  };
+
+  // Produces a string upon the successful (but unexpected) completion of an
+  // expectation.
+  class SuccessfulStateString {
+   public:
+    virtual std::string GetSuccessfulStateString() = 0;
+
+   protected:
+    ~SuccessfulStateString() = default;
   };
 
   static void FailUsingGprCrash(const Failure& failure);
@@ -98,6 +111,10 @@ class CqVerifier {
   void VerifyEmpty(Duration timeout = Duration::Seconds(1),
                    SourceLocation location = SourceLocation());
 
+  void ClearSuccessfulStateStrings(void* tag);
+  void AddSuccessfulStateString(void* tag,
+                                SuccessfulStateString* successful_state_string);
+
   // Match an expectation about a status.
   // location must be DEBUG_LOCATION.
   // result can be any of the types in ExpectedResult - a plain bool means
@@ -141,6 +158,8 @@ class CqVerifier {
   absl::AnyInvocable<void(
       grpc_event_engine::experimental::EventEngine::Duration) const>
       step_fn_;
+  absl::flat_hash_map<void*, std::vector<SuccessfulStateString*>>
+      successful_state_strings_;
   bool log_verifications_ = true;
 };
 
diff --git a/test/core/end2end/end2end_tests.cc b/test/core/end2end/end2end_tests.cc
index 5eef7f6fbe6..7500feb0181 100644
--- a/test/core/end2end/end2end_tests.cc
+++ b/test/core/end2end/end2end_tests.cc
@@ -136,8 +136,8 @@ grpc_op CoreEnd2endTest::IncomingMetadata::MakeOp() {
   return op;
 }
 
-std::string CoreEnd2endTest::IncomingMetadata::ToString() {
-  std::string out = "{";
+std::string CoreEnd2endTest::IncomingMetadata::GetSuccessfulStateString() {
+  std::string out = "incoming_metadata: {";
   for (size_t i = 0; i < metadata_->count; i++) {
     absl::StrAppend(&out, StringViewFromSlice(metadata_->metadata[i].key), ":",
                     StringViewFromSlice(metadata_->metadata[i].value), ",");
@@ -184,10 +184,11 @@ CoreEnd2endTest::IncomingStatusOnClient::GetTrailingMetadata(
   return FindInMetadataArray(data_->trailing_metadata, key);
 }
 
-std::string CoreEnd2endTest::IncomingStatusOnClient::ToString() {
-  std::string out =
-      absl::StrCat("{status:", data_->status,
-                   " msg:", data_->status_details.as_string_view(), " ");
+std::string
+CoreEnd2endTest::IncomingStatusOnClient::GetSuccessfulStateString() {
+  std::string out = absl::StrCat(
+      "status_on_client: status=", data_->status,
+      " msg=", data_->status_details.as_string_view(), " trailing_metadata={");
   for (size_t i = 0; i < data_->trailing_metadata.count; i++) {
     absl::StrAppend(
         &out, StringViewFromSlice(data_->trailing_metadata.metadata[i].key),
@@ -197,6 +198,11 @@ std::string CoreEnd2endTest::IncomingStatusOnClient::ToString() {
   return out + "}";
 }
 
+std::string CoreEnd2endTest::IncomingMessage::GetSuccessfulStateString() {
+  if (payload_ == nullptr) return "message: empty";
+  return absl::StrCat("message: ", payload().size(), "b uncompressed");
+}
+
 grpc_op CoreEnd2endTest::IncomingStatusOnClient::MakeOp() {
   grpc_op op;
   memset(&op, 0, sizeof(op));
@@ -298,19 +304,22 @@ CoreEnd2endTest::Call CoreEnd2endTest::ClientCallBuilder::Create() {
     absl::optional<Slice> host;
     if (u->host.has_value()) host = Slice::FromCopiedString(*u->host);
     test_.ForceInitialized();
-    return Call(grpc_channel_create_call(
-        test_.client(), parent_call_, propagation_mask_, test_.cq(),
-        Slice::FromCopiedString(u->method).c_slice(),
-        host.has_value() ? &host->c_slice() : nullptr, deadline_, nullptr));
+    return Call(
+        grpc_channel_create_call(
+            test_.client(), parent_call_, propagation_mask_, test_.cq(),
+            Slice::FromCopiedString(u->method).c_slice(),
+            host.has_value() ? &host->c_slice() : nullptr, deadline_, nullptr),
+        &test_);
   } else {
     return Call(grpc_channel_create_registered_call(
-        test_.client(), parent_call_, propagation_mask_, test_.cq(),
-        absl::get<void*>(call_selector_), deadline_, nullptr));
+                    test_.client(), parent_call_, propagation_mask_, test_.cq(),
+                    absl::get<void*>(call_selector_), deadline_, nullptr),
+                &test_);
   }
 }
 
 CoreEnd2endTest::IncomingCall::IncomingCall(CoreEnd2endTest& test, int tag)
-    : impl_(std::make_unique<Impl>()) {
+    : impl_(std::make_unique<Impl>(&test)) {
   test.ForceInitialized();
   grpc_server_request_call(test.server(), impl_->call.call_ptr(),
                            &impl_->call_details, &impl_->request_metadata,
diff --git a/test/core/end2end/end2end_tests.h b/test/core/end2end/end2end_tests.h
index 49d005aa2e4..a7fcb6aea45 100644
--- a/test/core/end2end/end2end_tests.h
+++ b/test/core/end2end/end2end_tests.h
@@ -34,6 +34,7 @@
 #include "absl/functional/any_invocable.h"
 #include "absl/memory/memory.h"
 #include "absl/meta/type_traits.h"
+#include "absl/strings/str_cat.h"
 #include "absl/strings/string_view.h"
 #include "absl/types/optional.h"
 #include "absl/types/variant.h"
@@ -217,7 +218,7 @@ class CoreEnd2endTest : public ::testing::Test {
   };
 
   // Receiving container for incoming metadata.
-  class IncomingMetadata {
+  class IncomingMetadata final : public CqVerifier::SuccessfulStateString {
    public:
     IncomingMetadata() = default;
     ~IncomingMetadata() {
@@ -231,7 +232,7 @@ class CoreEnd2endTest : public ::testing::Test {
     // for tests.
     grpc_op MakeOp();
 
-    std::string ToString();
+    std::string GetSuccessfulStateString() override;
 
    private:
     std::unique_ptr<grpc_metadata_array> metadata_ =
@@ -240,7 +241,7 @@ class CoreEnd2endTest : public ::testing::Test {
   };
 
   // Receiving container for one incoming message.
-  class IncomingMessage {
+  class IncomingMessage final : public CqVerifier::SuccessfulStateString {
    public:
     IncomingMessage() = default;
     IncomingMessage(const IncomingMessage&) = delete;
@@ -260,6 +261,7 @@ class CoreEnd2endTest : public ::testing::Test {
     grpc_compression_algorithm compression() const {
       return payload_->data.raw.compression;
     }
+    std::string GetSuccessfulStateString() override;
 
     // Make a GRPC_OP_RECV_MESSAGE op - intended for the framework, not for
     // tests.
@@ -270,7 +272,8 @@ class CoreEnd2endTest : public ::testing::Test {
   };
 
   // Receiving container for incoming status on the client from the server.
-  class IncomingStatusOnClient {
+  class IncomingStatusOnClient final
+      : public CqVerifier::SuccessfulStateString {
    public:
     IncomingStatusOnClient() = default;
     IncomingStatusOnClient(const IncomingStatusOnClient&) = delete;
@@ -299,7 +302,7 @@ class CoreEnd2endTest : public ::testing::Test {
     absl::optional<std::string> GetTrailingMetadata(
         absl::string_view key) const;
 
-    std::string ToString();
+    std::string GetSuccessfulStateString() override;
 
     // Make a GRPC_OP_RECV_STATUS_ON_CLIENT op - intended for the framework, not
     // for tests.
@@ -316,7 +319,7 @@ class CoreEnd2endTest : public ::testing::Test {
   };
 
   // Receiving container for incoming status on the server from the client.
-  class IncomingCloseOnServer {
+  class IncomingCloseOnServer final : public CqVerifier::SuccessfulStateString {
    public:
     IncomingCloseOnServer() = default;
     IncomingCloseOnServer(const IncomingCloseOnServer&) = delete;
@@ -329,6 +332,10 @@ class CoreEnd2endTest : public ::testing::Test {
     // for tests.
     grpc_op MakeOp();
 
+    std::string GetSuccessfulStateString() override {
+      return absl::StrCat("close_on_server: cancelled=", cancelled_);
+    }
+
    private:
     int cancelled_;
   };
@@ -338,7 +345,10 @@ class CoreEnd2endTest : public ::testing::Test {
   // added batches.
   class BatchBuilder {
    public:
-    BatchBuilder(grpc_call* call, int tag) : call_(call), tag_(tag) {}
+    BatchBuilder(grpc_call* call, CoreEnd2endTest* test, int tag)
+        : call_(call), tag_(tag), cq_verifier_(&test->cq_verifier()) {
+      cq_verifier_->ClearSuccessfulStateStrings(CqVerifier::tag(tag_));
+    }
     ~BatchBuilder();
 
     BatchBuilder(const BatchBuilder&) = delete;
@@ -371,24 +381,28 @@ class CoreEnd2endTest : public ::testing::Test {
 
     // Add a GRPC_OP_RECV_INITIAL_METADATA op.
     BatchBuilder& RecvInitialMetadata(IncomingMetadata& md) {
+      cq_verifier_->AddSuccessfulStateString(CqVerifier::tag(tag_), &md);
       ops_.emplace_back(md.MakeOp());
       return *this;
     }
 
     // Add a GRPC_OP_RECV_MESSAGE op.
     BatchBuilder& RecvMessage(IncomingMessage& msg) {
+      cq_verifier_->AddSuccessfulStateString(CqVerifier::tag(tag_), &msg);
       ops_.emplace_back(msg.MakeOp());
       return *this;
     }
 
     // Add a GRPC_OP_RECV_STATUS_ON_CLIENT op.
     BatchBuilder& RecvStatusOnClient(IncomingStatusOnClient& status) {
+      cq_verifier_->AddSuccessfulStateString(CqVerifier::tag(tag_), &status);
       ops_.emplace_back(status.MakeOp());
       return *this;
     }
 
     // Add a GRPC_OP_RECV_CLOSE_ON_SERVER op.
     BatchBuilder& RecvCloseOnServer(IncomingCloseOnServer& close) {
+      cq_verifier_->AddSuccessfulStateString(CqVerifier::tag(tag_), &close);
       ops_.emplace_back(close.MakeOp());
       return *this;
     }
@@ -427,6 +441,7 @@ class CoreEnd2endTest : public ::testing::Test {
     const int tag_;
     std::vector<grpc_op> ops_;
     std::vector<std::unique_ptr<Thing>> things_;
+    CqVerifier* const cq_verifier_;
   };
 
   // Wrapper around a grpc_call.
@@ -434,16 +449,18 @@ class CoreEnd2endTest : public ::testing::Test {
   // Wrapped by IncomingCall for server calls.
   class Call {
    public:
-    explicit Call(grpc_call* call) : call_(call) {}
+    Call(grpc_call* call, CoreEnd2endTest* test) : call_(call), test_(test) {}
     Call(const Call&) = delete;
     Call& operator=(const Call&) = delete;
-    Call(Call&& other) noexcept : call_(std::exchange(other.call_, nullptr)) {}
+    Call(Call&& other) noexcept
+        : call_(std::exchange(other.call_, nullptr)),
+          test_(std::exchange(other.test_, nullptr)) {}
     ~Call() {
       if (call_ != nullptr) grpc_call_unref(call_);
     }
     // Construct a batch with a tag - upon destruction of the BatchBuilder the
     // operation will occur.
-    BatchBuilder NewBatch(int tag) { return BatchBuilder(call_, tag); }
+    BatchBuilder NewBatch(int tag) { return BatchBuilder(call_, test_, tag); }
     // Cancel the call
     void Cancel() { grpc_call_cancel(call_, nullptr); }
     void CancelWithStatus(grpc_status_code status, const char* message) {
@@ -478,6 +495,7 @@ class CoreEnd2endTest : public ::testing::Test {
 
    private:
     grpc_call* call_ = nullptr;
+    CoreEnd2endTest* test_;
   };
 
   // Wrapper around a server call.
@@ -526,7 +544,7 @@ class CoreEnd2endTest : public ::testing::Test {
 
    private:
     struct Impl {
-      Impl() {
+      explicit Impl(CoreEnd2endTest* test) : call(nullptr, test) {
         grpc_call_details_init(&call_details);
         grpc_metadata_array_init(&request_metadata);
       }
@@ -534,7 +552,7 @@ class CoreEnd2endTest : public ::testing::Test {
         grpc_call_details_destroy(&call_details);
         grpc_metadata_array_destroy(&request_metadata);
       }
-      Call call{nullptr};
+      Call call;
       grpc_call_details call_details;
       grpc_metadata_array request_metadata;
     };
@@ -561,7 +579,7 @@ class CoreEnd2endTest : public ::testing::Test {
   // Expect a tag with some result.
   void Expect(int tag, ExpectedResult result, SourceLocation whence = {}) {
     expectations_++;
-    cq_verifier().Expect(CqVerifier::tag(tag), result, whence);
+    cq_verifier().Expect(CqVerifier::tag(tag), std::move(result), whence);
   }
   // Step the system until expectations are met or until timeout is reached.
   // If there are no expectations logged, then step for 1 second and verify that
diff --git a/test/core/end2end/tests/call_host_override.cc b/test/core/end2end/tests/call_host_override.cc
index 2d732691c54..9847497bdbc 100644
--- a/test/core/end2end/tests/call_host_override.cc
+++ b/test/core/end2end/tests/call_host_override.cc
@@ -16,7 +16,6 @@
 //
 //
 
-#include "absl/strings/str_cat.h"
 #include "absl/types/optional.h"
 #include "gtest/gtest.h"
 
@@ -24,7 +23,6 @@
 #include <grpc/status.h>
 
 #include "src/core/lib/channel/channel_args.h"
-#include "src/core/lib/gprpp/crash.h"
 #include "src/core/lib/gprpp/time.h"
 #include "test/core/end2end/end2end_tests.h"
 
@@ -49,12 +47,6 @@ CORE_END2END_TEST(CoreClientChannelTest, CallHostOverride) {
       .RecvStatusOnClient(server_status);
   auto s = RequestCall(101);
   Expect(101, true);
-  Expect(1, CoreEnd2endTest::MaybePerformAction{[&](bool success) {
-           Crash(absl::StrCat(
-               "Unexpected completion of client side call: success=",
-               success ? "true" : "false", " status=", server_status.ToString(),
-               " initial_md=", server_initial_metadata.ToString()));
-         }});
   Step();
   EXPECT_NE(s.GetPeer(), absl::nullopt);
   EXPECT_NE(c.GetPeer(), absl::nullopt);
diff --git a/test/core/end2end/tests/disappearing_server.cc b/test/core/end2end/tests/disappearing_server.cc
index 098762619f5..557e6ab2383 100644
--- a/test/core/end2end/tests/disappearing_server.cc
+++ b/test/core/end2end/tests/disappearing_server.cc
@@ -16,14 +16,12 @@
 //
 //
 
-#include "absl/strings/str_cat.h"
 #include "gtest/gtest.h"
 
 #include <grpc/status.h>
 #include <grpc/support/log.h>
 
 #include "src/core/lib/channel/channel_args.h"
-#include "src/core/lib/gprpp/crash.h"
 #include "src/core/lib/gprpp/time.h"
 #include "test/core/end2end/end2end_tests.h"
 
@@ -45,13 +43,6 @@ static void OneRequestAndShutdownServer(CoreEnd2endTest& test) {
       .RecvStatusOnClient(server_status);
   auto s = test.RequestCall(101);
   test.Expect(101, true);
-  test.Expect(
-      1, CoreEnd2endTest::MaybePerformAction{[&](bool success) {
-        Crash(absl::StrCat(
-            "Unexpected completion of client side call: success=",
-            success ? "true" : "false", " status=", server_status.ToString(),
-            " initial_md=", server_initial_md.ToString()));
-      }});
   test.Step();
   test.ShutdownServerAndNotify(1000);
   CoreEnd2endTest::IncomingCloseOnServer client_closed;
diff --git a/test/core/end2end/tests/request_with_payload.cc b/test/core/end2end/tests/request_with_payload.cc
index 79fba04bf05..370a65ee588 100644
--- a/test/core/end2end/tests/request_with_payload.cc
+++ b/test/core/end2end/tests/request_with_payload.cc
@@ -16,12 +16,10 @@
 //
 //
 
-#include "absl/strings/str_cat.h"
 #include "gtest/gtest.h"
 
 #include <grpc/status.h>
 
-#include "src/core/lib/gprpp/crash.h"
 #include "src/core/lib/gprpp/time.h"
 #include "test/core/end2end/end2end_tests.h"
 
@@ -40,12 +38,6 @@ CORE_END2END_TEST(CoreEnd2endTest, RequestWithPayload) {
       .RecvStatusOnClient(server_status);
   auto s = RequestCall(101);
   Expect(101, true);
-  Expect(1, CoreEnd2endTest::MaybePerformAction{[&](bool success) {
-           Crash(absl::StrCat(
-               "Unexpected completion of client side call: success=",
-               success ? "true" : "false", " status=", server_status.ToString(),
-               " initial_md=", server_initial_metadata.ToString()));
-         }});
   Step();
   IncomingMessage client_message;
   s.NewBatch(102).SendInitialMetadata({}).RecvMessage(client_message);
diff --git a/test/core/end2end/tests/simple_delayed_request.cc b/test/core/end2end/tests/simple_delayed_request.cc
index 6ae1c51b4b7..495cc649ddc 100644
--- a/test/core/end2end/tests/simple_delayed_request.cc
+++ b/test/core/end2end/tests/simple_delayed_request.cc
@@ -16,7 +16,6 @@
 //
 //
 
-#include "absl/strings/str_cat.h"
 #include "gtest/gtest.h"
 
 #include <grpc/grpc.h>
@@ -24,7 +23,6 @@
 #include <grpc/support/log.h>
 
 #include "src/core/lib/channel/channel_args.h"
-#include "src/core/lib/gprpp/crash.h"
 #include "src/core/lib/gprpp/time.h"
 #include "test/core/end2end/end2end_tests.h"
 
@@ -50,12 +48,6 @@ CORE_END2END_TEST(Http2SingleHopTest, SimpleDelayedRequestShort) {
   InitServer(ChannelArgs());
   auto s = RequestCall(101);
   Expect(101, true);
-  Expect(1, CoreEnd2endTest::MaybePerformAction{[&](bool success) {
-           Crash(absl::StrCat(
-               "Unexpected completion of client side call: success=",
-               success ? "true" : "false", " status=", server_status.ToString(),
-               " initial_md=", server_initial_metadata.ToString()));
-         }});
   Step();
   IncomingCloseOnServer client_close;
   s.NewBatch(102)
diff --git a/test/core/end2end/tests/simple_request.cc b/test/core/end2end/tests/simple_request.cc
index 328b5bfe048..ceeb7699562 100644
--- a/test/core/end2end/tests/simple_request.cc
+++ b/test/core/end2end/tests/simple_request.cc
@@ -23,7 +23,6 @@
 #include <string>
 
 #include "absl/strings/match.h"
-#include "absl/strings/str_cat.h"
 #include "absl/types/optional.h"
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
@@ -33,7 +32,6 @@
 
 #include "src/core/lib/debug/stats.h"
 #include "src/core/lib/debug/stats_data.h"
-#include "src/core/lib/gprpp/crash.h"
 #include "src/core/lib/gprpp/time.h"
 #include "test/core/end2end/end2end_tests.h"
 
@@ -62,13 +60,6 @@ void SimpleRequestBody(CoreEnd2endTest& test) {
       .RecvStatusOnClient(server_status);
   auto s = test.RequestCall(101);
   test.Expect(101, true);
-  test.Expect(
-      1, CoreEnd2endTest::MaybePerformAction{[&](bool success) {
-        Crash(absl::StrCat(
-            "Unexpected completion of client side call: success=",
-            success ? "true" : "false", " status=", server_status.ToString(),
-            " initial_md=", server_initial_metadata.ToString()));
-      }});
   test.Step();
   EXPECT_NE(s.GetPeer(), absl::nullopt);
   CheckPeer(*s.GetPeer());