diff --git a/tests/ansible/integration/action/copy.yml b/tests/ansible/integration/action/copy.yml
index b34b9831..1cab2b34 100644
--- a/tests/ansible/integration/action/copy.yml
+++ b/tests/ansible/integration/action/copy.yml
@@ -63,6 +63,7 @@
         - stat.results[1].stat.checksum == "62951f943c41cdd326e5ce2b53a779e7916a820d"
         - stat.results[2].stat.checksum == "b26dd6444595e2bdb342aa0a91721b57478b5029"
         - stat.results[3].stat.checksum == "d675f47e467eae19e49032a2cc39118e12a6ee72"
+        fail_msg: stat={{stat}}
 
     - file:
         state: absent
diff --git a/tests/ansible/integration/action/fixup_perms2__copy.yml b/tests/ansible/integration/action/fixup_perms2__copy.yml
index 1331f9bb..e5b10005 100644
--- a/tests/ansible/integration/action/fixup_perms2__copy.yml
+++ b/tests/ansible/integration/action/fixup_perms2__copy.yml
@@ -21,6 +21,7 @@
     - assert:
         that:
         -  out.stat.mode in ("0644", "0664")
+        fail_msg: out={{out}}
 
     #
     # copy module (explicit mode).
@@ -37,6 +38,7 @@
     - assert:
         that:
         -  out.stat.mode == "0400"
+        fail_msg: out={{out}}
 
     #
     # copy module (existing disk files, no mode).
@@ -63,6 +65,7 @@
     - assert:
         that:
         - out.stat.mode in ("0644", "0664")
+        fail_msg: out={{out}}
 
     #
     # copy module (existing disk files, preserve mode).
@@ -79,6 +82,7 @@
     - assert:
         that:
         - out.stat.mode == "1462"
+        fail_msg: out={{out}}
 
     #
     # copy module (existing disk files, explicit mode).
@@ -96,6 +100,7 @@
     - assert:
         that:
         - out.stat.mode == "1461"
+        fail_msg: out={{out}}
 
     - file:
         state: absent
diff --git a/tests/ansible/integration/action/low_level_execute_command.yml b/tests/ansible/integration/action/low_level_execute_command.yml
index 7c14cb22..7dc74473 100644
--- a/tests/ansible/integration/action/low_level_execute_command.yml
+++ b/tests/ansible/integration/action/low_level_execute_command.yml
@@ -16,6 +16,7 @@
           - 'raw.rc == 0'
           - 'raw.stdout_lines[-1]|to_text == "2"'
           - 'raw.stdout[-1]|to_text == "2"'
+        fail_msg: raw={{raw}}
 
     - name: Run raw module with sudo
       become: true
@@ -39,3 +40,4 @@
             ["root\r\n"],
             ["root"],
           )
+        fail_msg: raw={{raw}}
diff --git a/tests/ansible/integration/action/make_tmp_path.yml b/tests/ansible/integration/action/make_tmp_path.yml
index 0a018d4c..ab2db0fb 100644
--- a/tests/ansible/integration/action/make_tmp_path.yml
+++ b/tests/ansible/integration/action/make_tmp_path.yml
@@ -44,11 +44,13 @@
       assert:
         that:
         - good_temp_path == good_temp_path2
+        fail_msg: good_temp_path={{good_temp_path}} good_temp_path2={{good_temp_path2}}
 
     - name: "Verify different subdir for both tasks"
       assert:
         that:
         - tmp_path.path != tmp_path2.path
+        fail_msg: tmp_path={{tmp_path}} tmp_path2={{tmp_path2}}
 
     #
     # Verify subdirectory removal.
@@ -69,6 +71,7 @@
         that:
         - not stat1.stat.exists
         - not stat2.stat.exists
+        fail_msg: stat1={{stat1}} stat2={{stat2}}
 
     #
     # Verify good directory persistence.
@@ -83,6 +86,7 @@
       assert:
         that:
         - stat.stat.exists
+        fail_msg: stat={{stat}}
 
     #
     # Write some junk into the temp path.
@@ -105,6 +109,7 @@
     - assert:
         that:
         - not out.stat.exists
+        fail_msg: out={{out}}
 
     #
     # root
@@ -123,6 +128,7 @@
         that:
         - tmp_path2.path != tmp_path_root.path
         - tmp_path2.path|dirname != tmp_path_root.path|dirname
+        fail_msg: tmp_path_root={{tmp_path_root}} tmp_path2={{tmp_path2}}
 
     #
     # readonly homedir
@@ -153,3 +159,4 @@
         that:
         - out.module_path.startswith(good_temp_path2)
         - out.module_tmpdir.startswith(good_temp_path2)
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/action/remote_expand_user.yml b/tests/ansible/integration/action/remote_expand_user.yml
index 37fc5ebe..851da502 100644
--- a/tests/ansible/integration/action/remote_expand_user.yml
+++ b/tests/ansible/integration/action/remote_expand_user.yml
@@ -27,6 +27,7 @@
       register: out
     - assert:
         that: out.result == '{{user_facts.ansible_facts.ansible_user_dir}}/foo'
+        fail_msg: out={{out}}
 
     - name: "Expand ~/foo with become active. ~ is become_user's home."
       action_passthrough:
@@ -49,6 +50,7 @@
       register: out
     - assert:
         that: out.result == '{{user_facts.ansible_facts.ansible_user_dir}}/foo'
+        fail_msg: out={{out}}
 
     - name: "Expanding $HOME/foo has no effect."
       action_passthrough:
@@ -59,6 +61,7 @@
       register: out
     - assert:
         that: out.result == '$HOME/foo'
+        fail_msg: out={{out}}
 
     # ------------------------
 
@@ -71,6 +74,7 @@
       register: out
     - assert:
         that: out.result == '{{user_facts.ansible_facts.ansible_user_dir}}/foo'
+        fail_msg: out={{out}}
 
     - name: "sudoable; Expand ~/foo with become active. ~ is become_user's home."
       action_passthrough:
@@ -94,6 +98,7 @@
       register: out
     - assert:
         that: out.result == '{{user_facts.ansible_facts.ansible_user_dir}}/foo'
+        fail_msg: out={{out}}
 
     - name: "sudoable; Expanding $HOME/foo has no effect."
       action_passthrough:
@@ -104,3 +109,4 @@
       register: out
     - assert:
         that: out.result == '$HOME/foo'
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/action/remote_file_exists.yml b/tests/ansible/integration/action/remote_file_exists.yml
index 20a825c8..209f7830 100644
--- a/tests/ansible/integration/action/remote_file_exists.yml
+++ b/tests/ansible/integration/action/remote_file_exists.yml
@@ -15,6 +15,7 @@
 
     - assert:
         that: out.result == False
+        fail_msg: out={{out}}
 
     # ---
 
@@ -29,6 +30,7 @@
 
     - assert:
         that: out.result == True
+        fail_msg: out={{out}}
 
     - file:
         path: /tmp/does-exist
diff --git a/tests/ansible/integration/action/remove_tmp_path.yml b/tests/ansible/integration/action/remove_tmp_path.yml
index 7a0c6c25..19d18e34 100644
--- a/tests/ansible/integration/action/remove_tmp_path.yml
+++ b/tests/ansible/integration/action/remove_tmp_path.yml
@@ -23,6 +23,7 @@
     - assert:
         that:
         - not out2.stat.exists
+        fail_msg: out={{out}}
 
     - stat:
         path: "{{out.src|dirname}}"
@@ -31,6 +32,7 @@
     - assert:
         that:
         - not out2.stat.exists
+        fail_msg: out={{out}}
 
     - file:
         path: /tmp/remove_tmp_path_test
diff --git a/tests/ansible/integration/action/synchronize.yml b/tests/ansible/integration/action/synchronize.yml
index 31cfe553..64ff9735 100644
--- a/tests/ansible/integration/action/synchronize.yml
+++ b/tests/ansible/integration/action/synchronize.yml
@@ -60,6 +60,7 @@
 
         - assert:
             that: outout == "item!"
+            fail_msg: outout={{outout}}
       when: False
 
     # TODO: https://github.com/dw/mitogen/issues/692
diff --git a/tests/ansible/integration/action/transfer_data.yml b/tests/ansible/integration/action/transfer_data.yml
index bbd39309..0f56672c 100644
--- a/tests/ansible/integration/action/transfer_data.yml
+++ b/tests/ansible/integration/action/transfer_data.yml
@@ -24,6 +24,7 @@
     - assert:
         that: |
           out.content|b64decode == '{"I am JSON": true}'
+        fail_msg: out={{out}}
 
 
     # Ensure it handles strings.
@@ -40,6 +41,7 @@
     - assert:
         that:
           out.content|b64decode == 'I am text.'
+        fail_msg: out={{out}}
 
     - file:
         path: /tmp/transfer-data
diff --git a/tests/ansible/integration/async/multiple_items_loop.yml b/tests/ansible/integration/async/multiple_items_loop.yml
index 9a9b1192..05db9652 100644
--- a/tests/ansible/integration/async/multiple_items_loop.yml
+++ b/tests/ansible/integration/async/multiple_items_loop.yml
@@ -34,3 +34,4 @@
       - out.results[1].stdout == 'hi-from-job-2'
       - out.results[1].rc == 0
       - out.results[1].delta > '0:00:05'
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/async/result_binary_producing_json.yml b/tests/ansible/integration/async/result_binary_producing_json.yml
index f81d0bb2..427fa58b 100644
--- a/tests/ansible/integration/async/result_binary_producing_json.yml
+++ b/tests/ansible/integration/async/result_binary_producing_json.yml
@@ -28,6 +28,7 @@
         (job.started == 1) and
         (job.changed == True) and
         (job.finished == 0)
+      fail_msg: job={{job}}
 
   - name: busy-poll up to 100000 times
     async_status:
@@ -51,5 +52,6 @@
         - async_out.failed == False
         - async_out.msg == "Hello, world."
         - 'async_out.stderr == "binary_producing_json: oh noes\n"'
+      fail_msg: async_out={{async_out}}
     vars:
       async_out: "{{result.content|b64decode|from_json}}"
diff --git a/tests/ansible/integration/async/result_binary_producing_junk.yml b/tests/ansible/integration/async/result_binary_producing_junk.yml
index 87877db7..25ad65cf 100644
--- a/tests/ansible/integration/async/result_binary_producing_junk.yml
+++ b/tests/ansible/integration/async/result_binary_producing_junk.yml
@@ -39,5 +39,6 @@
         - async_out.msg.startswith("Traceback")
         - '"ValueError: No start of json char found\n" in async_out.msg'
         - 'async_out.stderr == "binary_producing_junk: oh noes\n"'
+      fail_msg: async_out={{async_out}}
     vars:
       async_out: "{{result.content|b64decode|from_json}}"
diff --git a/tests/ansible/integration/async/result_shell_echo_hi.yml b/tests/ansible/integration/async/result_shell_echo_hi.yml
index e1068587..047913e5 100644
--- a/tests/ansible/integration/async/result_shell_echo_hi.yml
+++ b/tests/ansible/integration/async/result_shell_echo_hi.yml
@@ -35,12 +35,14 @@
         - async_out.start.startswith("20")
         - async_out.stderr == "there"
         - async_out.stdout == "hi"
+      fail_msg: async_out={{async_out}}
     vars:
       async_out: "{{result.content|b64decode|from_json}}"
 
   - assert:
       that:
         - async_out.invocation.module_args.stdin == None
+      fail_msg: async_out={{async_out}}
     when: ansible_version.full > '2.4'
     vars:
       async_out: "{{result.content|b64decode|from_json}}"
diff --git a/tests/ansible/integration/async/runner_new_process.yml b/tests/ansible/integration/async/runner_new_process.yml
index 7b0bf628..1644364f 100644
--- a/tests/ansible/integration/async/runner_new_process.yml
+++ b/tests/ansible/integration/async/runner_new_process.yml
@@ -16,6 +16,7 @@
   - assert:
       that:
       - sync_proc1.pid == sync_proc2.pid
+      fail_msg: sync_proc1={{sync_proc1}} sync_proc2={{sync_proc2}}
     when: is_mitogen
 
   - name: get async process ID.
@@ -48,7 +49,9 @@
 
   - assert:
       that:
+      # FIXME should this be async_proc1, and async_proc2?
       - sync_proc1.pid == sync_proc2.pid
       - async_result1.pid != sync_proc1.pid
       - async_result1.pid != async_result2.pid
+      fail_msg: async_result1={{async_result1}} async_result2={{async_result2}}
     when: is_mitogen
diff --git a/tests/ansible/integration/async/runner_one_job.yml b/tests/ansible/integration/async/runner_one_job.yml
index bea6ed9c..b8a7a564 100644
--- a/tests/ansible/integration/async/runner_one_job.yml
+++ b/tests/ansible/integration/async/runner_one_job.yml
@@ -24,6 +24,7 @@
         (job1.started == 1) and
         (job1.changed == True) and
         (job1.finished == 0)
+      fail_msg: job1={{job1}}
 
   - name: busy-poll up to 100000 times
     async_status:
@@ -48,6 +49,7 @@
       - result1.start|length == 26
       - result1.finished == 1
       - result1.rc == 0
+      fail_msg: result1={{result1}}
 
   - assert:
       that:
@@ -55,9 +57,11 @@
       - result1.stderr_lines == []
       - result1.stdout == "alldone"
       - result1.stdout_lines == ["alldone"]
+      fail_msg: result1={{result1}}
     when: ansible_version.full is version('2.8', '>')  # ansible#51393
 
   - assert:
       that:
       - result1.failed == False
+      fail_msg: result1={{result1}}
     when: ansible_version.full is version('2.4', '>')
diff --git a/tests/ansible/integration/async/runner_timeout_then_polling.yml b/tests/ansible/integration/async/runner_timeout_then_polling.yml
index 5490e711..0847a95f 100644
--- a/tests/ansible/integration/async/runner_timeout_then_polling.yml
+++ b/tests/ansible/integration/async/runner_timeout_then_polling.yml
@@ -31,4 +31,5 @@
         - result.failed == 1
         - result.finished == 1
         - result.msg == "Job reached maximum time limit of 1 seconds."
+      fail_msg: result={{result}}
     when: is_mitogen
diff --git a/tests/ansible/integration/async/runner_two_simultaneous_jobs.yml b/tests/ansible/integration/async/runner_two_simultaneous_jobs.yml
index fdde0463..fd5292d1 100644
--- a/tests/ansible/integration/async/runner_two_simultaneous_jobs.yml
+++ b/tests/ansible/integration/async/runner_two_simultaneous_jobs.yml
@@ -56,8 +56,10 @@
       that:
         - result1.rc == 0
         - result2.rc == 0
+      fail_msg: result1={{result1}} result2={{result2}}
 
   - assert:
       that:
         - result2.stdout == 'im_alive'
+      fail_msg: result2={{result2}}
     when: ansible_version.full > '2.8'  # ansible#51393
diff --git a/tests/ansible/integration/async/runner_with_polling_and_timeout.yml b/tests/ansible/integration/async/runner_with_polling_and_timeout.yml
index dcfa186f..c7d9338e 100644
--- a/tests/ansible/integration/async/runner_with_polling_and_timeout.yml
+++ b/tests/ansible/integration/async/runner_with_polling_and_timeout.yml
@@ -22,4 +22,5 @@
           job1.msg == "async task did not complete within the requested time" or
           job1.msg == "async task did not complete within the requested time - 1s" or
           job1.msg == "Job reached maximum time limit of 1 seconds."
+      fail_msg: job1={{job1}}
 
diff --git a/tests/ansible/integration/become/su_password.yml b/tests/ansible/integration/become/su_password.yml
index f6eb0b47..9e1d0cf4 100644
--- a/tests/ansible/integration/become/su_password.yml
+++ b/tests/ansible/integration/become/su_password.yml
@@ -22,6 +22,7 @@
             ('password is required' in out.msg) or
             ('password is required' in out.module_stderr)
           )
+        fail_msg: out={{out}}
       when: is_mitogen
 
 
@@ -41,6 +42,7 @@
             ('Incorrect su password' in out.msg) or
             ('su password is incorrect' in out.msg)
           )
+        fail_msg: out={{out}}
       when: is_mitogen
 
     - name: Ensure password su succeeds.
@@ -55,4 +57,5 @@
     - assert:
         that:
           - out.stdout == 'mitogen__user1'
+        fail_msg: out={{out}}
       when: is_mitogen
diff --git a/tests/ansible/integration/become/sudo_flags_failure.yml b/tests/ansible/integration/become/sudo_flags_failure.yml
index 39fbb4b8..290f1356 100644
--- a/tests/ansible/integration/become/sudo_flags_failure.yml
+++ b/tests/ansible/integration/become/sudo_flags_failure.yml
@@ -20,3 +20,4 @@
             ("sudo: invalid option -- '-'" in out.module_stderr) or
             ("sudo: unrecognized option `--derps'" in out.module_stderr) or
             ("sudo: unrecognized option '--derps'" in out.module_stderr)
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/become/sudo_nonexistent.yml b/tests/ansible/integration/become/sudo_nonexistent.yml
index 09ab91bb..3f6a2dc6 100644
--- a/tests/ansible/integration/become/sudo_nonexistent.yml
+++ b/tests/ansible/integration/become/sudo_nonexistent.yml
@@ -19,3 +19,4 @@
           - >-
             ('sudo: unknown user: slartibartfast' in out.module_stderr | default(out.msg))
             or (ansible_facts.os_family == 'RedHat' and ansible_facts.distribution_version == '6.10')
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/become/sudo_nopassword.yml b/tests/ansible/integration/become/sudo_nopassword.yml
index 03644423..6b074667 100644
--- a/tests/ansible/integration/become/sudo_nopassword.yml
+++ b/tests/ansible/integration/become/sudo_nopassword.yml
@@ -12,6 +12,7 @@
     - assert:
         that:
           - out.stdout != 'root'
+        fail_msg: out={{out}}
 
     - name: Ensure passwordless sudo to root succeeds.
       shell: whoami
@@ -22,3 +23,4 @@
     - assert:
         that:
           - out.stdout == 'root'
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/become/sudo_password.yml b/tests/ansible/integration/become/sudo_password.yml
index 145c8d69..6653c3e9 100644
--- a/tests/ansible/integration/become/sudo_password.yml
+++ b/tests/ansible/integration/become/sudo_password.yml
@@ -19,6 +19,7 @@
             ('Missing sudo password' in out.msg) or
             ('password is required' in out.module_stderr)
           )
+        fail_msg: out={{out}}
 
     - name: Ensure password sudo incorrect.
       shell: whoami
@@ -35,6 +36,7 @@
             ('Incorrect sudo password' in out.msg) or
             ('sudo password is incorrect' in out.msg)
           )
+        fail_msg: out={{out}}
 
     # TODO: https://github.com/dw/mitogen/issues/692
     # - name: Ensure password sudo succeeds.
diff --git a/tests/ansible/integration/connection/_put_file.yml b/tests/ansible/integration/connection/_put_file.yml
index 5b661d9f..3092e199 100644
--- a/tests/ansible/integration/connection/_put_file.yml
+++ b/tests/ansible/integration/connection/_put_file.yml
@@ -21,3 +21,4 @@
     - original.stat.checksum == copied.stat.checksum
     # Upstream does not preserve timestamps at al.
     #- (not is_mitogen) or (original.stat.mtime|int == copied.stat.mtime|int)
+    fail_msg: original={{original}} copied={{copied}}
diff --git a/tests/ansible/integration/connection/become_same_user.yml b/tests/ansible/integration/connection/become_same_user.yml
index d73eca86..7e5e5244 100644
--- a/tests/ansible/integration/connection/become_same_user.yml
+++ b/tests/ansible/integration/connection/become_same_user.yml
@@ -19,6 +19,7 @@
       - out.result[0].method == "ssh"
       - out.result[0].kwargs.username == "joe"
       - out.result|length == 1  # no sudo
+      fail_msg: out={{out}}
     when: is_mitogen
 
 
@@ -36,4 +37,5 @@
       - out.result[1].method == "sudo"
       - out.result[1].kwargs.username == "james"
       - out.result|length == 2  # no sudo
+      fail_msg: out={{out}}
     when: is_mitogen
diff --git a/tests/ansible/integration/connection/disconnect_during_module.yml b/tests/ansible/integration/connection/disconnect_during_module.yml
index e628e68e..723f61fc 100644
--- a/tests/ansible/integration/connection/disconnect_during_module.yml
+++ b/tests/ansible/integration/connection/disconnect_during_module.yml
@@ -25,3 +25,4 @@
       that:
       - out.rc == 4
       - "'Mitogen was disconnected from the remote environment while a call was in-progress.' in out.stdout"
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/connection/exec_command.yml b/tests/ansible/integration/connection/exec_command.yml
index 105505d1..a0dd71f7 100644
--- a/tests/ansible/integration/connection/exec_command.yml
+++ b/tests/ansible/integration/connection/exec_command.yml
@@ -17,3 +17,4 @@
       - out.result[0] == 0
       - out.result[1].decode() == "hello, world\r\n"
       - out.result[2].decode().startswith("Shared connection to ")
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/connection/reset.yml b/tests/ansible/integration/connection/reset.yml
index 768cd2d5..431f795b 100644
--- a/tests/ansible/integration/connection/reset.yml
+++ b/tests/ansible/integration/connection/reset.yml
@@ -43,3 +43,4 @@
 
         # sudo PID has changed.
         - out_become.ppid != out_become2.ppid
+        fail_msg: out={{out}} out2={{out2}} out_become={{out_become}} out_become2={{out_become2}}
diff --git a/tests/ansible/integration/connection/reset_become.yml b/tests/ansible/integration/connection/reset_become.yml
index 5a411e82..2b4161f2 100644
--- a/tests/ansible/integration/connection/reset_become.yml
+++ b/tests/ansible/integration/connection/reset_become.yml
@@ -24,6 +24,7 @@
     assert:
       that:
       - become_acct.pid != login_acct.pid
+      fail_msg: become_acct={{become_acct}} login_acct={{login_acct}}
 
   - name: reset the connection
     meta: reset_connection
@@ -36,6 +37,7 @@
     assert:
       that:
       - become_acct.pid != new_become_acct.pid
+      fail_msg: become_acct={{become_acct}} new_become_acct={{new_become_acct}}
 
   - name: save new pid of login acct
     become: false
@@ -46,3 +48,4 @@
     assert:
       that:
       - login_acct.pid != new_login_acct.pid
+      fail_msg: login_acct={{login_acct}} new_login_acct={{new_login_acct}}
diff --git a/tests/ansible/integration/connection_loader/local_blemished.yml b/tests/ansible/integration/connection_loader/local_blemished.yml
index d0fcabba..1592f973 100644
--- a/tests/ansible/integration/connection_loader/local_blemished.yml
+++ b/tests/ansible/integration/connection_loader/local_blemished.yml
@@ -12,3 +12,4 @@
 
     - assert:
         that: (not not out.mitogen_loaded) == (not not is_mitogen)
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/connection_loader/paramiko_unblemished.yml b/tests/ansible/integration/connection_loader/paramiko_unblemished.yml
index a48bd3ca..db1c8bd7 100644
--- a/tests/ansible/integration/connection_loader/paramiko_unblemished.yml
+++ b/tests/ansible/integration/connection_loader/paramiko_unblemished.yml
@@ -15,4 +15,5 @@
 
         - assert:
             that: not out.mitogen_loaded
+            fail_msg: out={{out}}
       when: False
diff --git a/tests/ansible/integration/connection_loader/ssh_blemished.yml b/tests/ansible/integration/connection_loader/ssh_blemished.yml
index 04ada1e3..b97fe1ed 100644
--- a/tests/ansible/integration/connection_loader/ssh_blemished.yml
+++ b/tests/ansible/integration/connection_loader/ssh_blemished.yml
@@ -12,3 +12,4 @@
 
     - assert:
         that: (not not out.mitogen_loaded) == (not not is_mitogen)
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/context_service/reconnection.yml b/tests/ansible/integration/context_service/reconnection.yml
index eed1dfdb..c5cec967 100644
--- a/tests/ansible/integration/context_service/reconnection.yml
+++ b/tests/ansible/integration/context_service/reconnection.yml
@@ -31,3 +31,4 @@
     - assert:
         that:
           - old_become_env.pid != new_become_env.pid
+        fail_msg: old_become_env={{old_become_env}} new_become_env={{new_become_env}}
diff --git a/tests/ansible/integration/context_service/remote_name.yml b/tests/ansible/integration/context_service/remote_name.yml
index d7116ec1..e2d9acac 100644
--- a/tests/ansible/integration/context_service/remote_name.yml
+++ b/tests/ansible/integration/context_service/remote_name.yml
@@ -18,6 +18,7 @@
   - assert:
       that:
       - out.stdout is match('.*python([0-9.]+)?\(mitogen:[a-z]+@[^:]+:[0-9]+\)')
+      fail_msg: out={{out}}
 
   - shell: 'cat /proc/$PPID/cmdline | tr \\0 \\n'
     register: out
@@ -28,4 +29,5 @@
   - assert:
       that:
       - out.stdout is match('.*python([0-9.]+)?\(mitogen:ansible\)')
+      fail_msg: out={{out}}
 
diff --git a/tests/ansible/integration/glibc_caches/resolv_conf.yml b/tests/ansible/integration/glibc_caches/resolv_conf.yml
index da78c308..0f1ddf35 100644
--- a/tests/ansible/integration/glibc_caches/resolv_conf.yml
+++ b/tests/ansible/integration/glibc_caches/resolv_conf.yml
@@ -44,6 +44,7 @@
         - out.failed
         - '"Name or service not known" in out.msg or
            "Temporary failure in name resolution" in out.msg'
+        fail_msg: out={{out}}
       when: |
         ansible_virtualization_type == "docker" and
         ansible_python_version > "2.5"
diff --git a/tests/ansible/integration/interpreter_discovery/ansible_2_8_tests.yml b/tests/ansible/integration/interpreter_discovery/ansible_2_8_tests.yml
index a4aec22f..d5e515b4 100644
--- a/tests/ansible/integration/interpreter_discovery/ansible_2_8_tests.yml
+++ b/tests/ansible/integration/interpreter_discovery/ansible_2_8_tests.yml
@@ -49,6 +49,7 @@
               that:
               - auto_out.ansible_facts.discovered_interpreter_python is defined
               - echoout.running_python_interpreter == auto_out.ansible_facts.discovered_interpreter_python
+              fail_msg: auto_out={{auto_out}} echoout={{echoout}}
 
 
         - name: test that auto_legacy gives a dep warning when /usr/bin/python present but != auto result
@@ -66,6 +67,7 @@
             assert:
               that:
               - legacy.deprecations | default([]) | length > 0
+              fail_msg: legacy={{legacy}}
             # only check for a dep warning if legacy returned /usr/bin/python and auto didn't
             when: legacy.ansible_facts.discovered_interpreter_python == '/usr/bin/python' and
                   auto_out.ansible_facts.discovered_interpreter_python != '/usr/bin/python'
@@ -86,6 +88,7 @@
               that:
               - auto_silent_out.warnings is not defined
               - auto_silent_out.ansible_facts.discovered_interpreter_python == auto_out.ansible_facts.discovered_interpreter_python
+              fail_msg: auto_silent_out={{auto_silent_out}}
 
 
         - name: test that auto_legacy_silent never warns and got the same answer as auto_legacy
@@ -103,6 +106,7 @@
               that:
                 - legacy_silent.warnings is not defined
                 - legacy_silent.ansible_facts.discovered_interpreter_python == legacy.ansible_facts.discovered_interpreter_python
+              fail_msg: legacy_silent={{legacy_silent}}
 
         - name: ensure modules can't set discovered_interpreter_X or ansible_X_interpreter
           block:
@@ -127,6 +131,7 @@
             assert:
               that:
               - auto_out.ansible_facts.discovered_interpreter_python == '/usr/bin/python3'
+              fail_msg: auto_out={{auto_out}}
             when: distro == 'fedora' and distro_version is version('23', '>=')
 
           - name: rhel assertions
@@ -136,6 +141,7 @@
               - (auto_out.ansible_facts.discovered_interpreter_python == '/usr/bin/python' and distro_version is version('8','<')) or distro_version is version('8','>=')
               # rhel 8+
               - (auto_out.ansible_facts.discovered_interpreter_python == '/usr/libexec/platform-python' and distro_version is version('8','>=')) or distro_version is version('8','<')
+              fail_msg: auto_out={{auto_out}}
             when: distro in ('redhat', 'centos')
 
           - name: ubuntu assertions
@@ -145,12 +151,14 @@
               - (auto_out.ansible_facts.discovered_interpreter_python == '/usr/bin/python' and distro_version is version('16.04','<')) or distro_version is version('16.04','>=')
               # ubuntu >= 16
               - (auto_out.ansible_facts.discovered_interpreter_python == '/usr/bin/python3' and distro_version is version('16.04','>=')) or distro_version is version('16.04','<')
+              fail_msg: auto_out={{auto_out}}
             when: distro == 'ubuntu'
 
           - name: mac assertions
             assert:
               that:
               - auto_out.ansible_facts.discovered_interpreter_python == '/usr/bin/python'
+              fail_msg: auto_out={{auto_out}}
             when: os_family == 'Darwin'
 
           always:
diff --git a/tests/ansible/integration/local/cwd_preserved.yml b/tests/ansible/integration/local/cwd_preserved.yml
index e5c0f7a4..5549f156 100644
--- a/tests/ansible/integration/local/cwd_preserved.yml
+++ b/tests/ansible/integration/local/cwd_preserved.yml
@@ -19,4 +19,5 @@
 
   - assert:
       that: stat.stat.exists
+      fail_msg: stat={{stat}}
 
diff --git a/tests/ansible/integration/module_utils/adjacent_to_playbook.yml b/tests/ansible/integration/module_utils/adjacent_to_playbook.yml
index 63bd90b2..f47e147f 100644
--- a/tests/ansible/integration/module_utils/adjacent_to_playbook.yml
+++ b/tests/ansible/integration/module_utils/adjacent_to_playbook.yml
@@ -13,4 +13,5 @@
       that:
       - out.external1_path == "ansible/integration/module_utils/module_utils/external1.py"
       - out.external2_path == "ansible/lib/module_utils/external2.py"
+      fail_msg: out={{out}}
 
diff --git a/tests/ansible/integration/module_utils/from_config_path.yml b/tests/ansible/integration/module_utils/from_config_path.yml
index e469fe32..df3acd9b 100644
--- a/tests/ansible/integration/module_utils/from_config_path.yml
+++ b/tests/ansible/integration/module_utils/from_config_path.yml
@@ -12,4 +12,5 @@
       that:
       - out.external1_path == "ansible/lib/module_utils/external1.py"
       - out.external2_path == "ansible/lib/module_utils/external2.py"
+      fail_msg: out={{out}}
 
diff --git a/tests/ansible/integration/module_utils/from_config_path_pkg.yml b/tests/ansible/integration/module_utils/from_config_path_pkg.yml
index 5db3d124..81881aa1 100644
--- a/tests/ansible/integration/module_utils/from_config_path_pkg.yml
+++ b/tests/ansible/integration/module_utils/from_config_path_pkg.yml
@@ -11,4 +11,5 @@
   - assert:
       that:
       - out.extmod_path == "ansible/lib/module_utils/externalpkg/extmod.py"
+      fail_msg: out={{out}}
 
diff --git a/tests/ansible/integration/module_utils/roles/modrole/tasks/main.yml b/tests/ansible/integration/module_utils/roles/modrole/tasks/main.yml
index 2c7c3372..7686cae7 100644
--- a/tests/ansible/integration/module_utils/roles/modrole/tasks/main.yml
+++ b/tests/ansible/integration/module_utils/roles/modrole/tasks/main.yml
@@ -7,3 +7,4 @@
     that:
     - out.external3_path == "integration/module_utils/roles/modrole/module_utils/external3.py"
     - out.external2_path == "integration/module_utils/roles/modrole/module_utils/external2.py"
+    fail_msg: out={{out}}
diff --git a/tests/ansible/integration/module_utils/roles/overrides_modrole/tasks/main.yml b/tests/ansible/integration/module_utils/roles/overrides_modrole/tasks/main.yml
index 6ef4703a..11b1d8b9 100644
--- a/tests/ansible/integration/module_utils/roles/overrides_modrole/tasks/main.yml
+++ b/tests/ansible/integration/module_utils/roles/overrides_modrole/tasks/main.yml
@@ -6,3 +6,4 @@
 - assert:
     that:
     - out.path == "ansible/integration/module_utils/roles/override_modrole/module_utils/known_hosts.py"
+    fail_msg: out={{out}}
diff --git a/tests/ansible/integration/playbook_semantics/become_flags.yml b/tests/ansible/integration/playbook_semantics/become_flags.yml
index f2ab0b5d..96a283da 100644
--- a/tests/ansible/integration/playbook_semantics/become_flags.yml
+++ b/tests/ansible/integration/playbook_semantics/become_flags.yml
@@ -14,6 +14,7 @@
 
     - assert:
         that: "out.stdout == ''"
+        fail_msg: out={{out}}
 
 - hosts: test-targets
   any_errors_fatal: true
@@ -28,3 +29,4 @@
 
     - assert:
         that: "out2.stdout == '2'"
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/playbook_semantics/environment.yml b/tests/ansible/integration/playbook_semantics/environment.yml
index 1ac7f71d..7d6b5184 100644
--- a/tests/ansible/integration/playbook_semantics/environment.yml
+++ b/tests/ansible/integration/playbook_semantics/environment.yml
@@ -11,3 +11,4 @@
 
     - assert:
         that: "result.stdout == '123'"
+        fail_msg: result={{result}}
diff --git a/tests/ansible/integration/runner/_etc_environment_global.yml b/tests/ansible/integration/runner/_etc_environment_global.yml
index 2d22b952..7b769ef4 100644
--- a/tests/ansible/integration/runner/_etc_environment_global.yml
+++ b/tests/ansible/integration/runner/_etc_environment_global.yml
@@ -10,6 +10,7 @@
 
 - assert:
     that: echo.stdout == ""
+    fail_msg: echo={{echo}}
 
 - copy:
     dest: /etc/environment
@@ -27,6 +28,7 @@
 
 - assert:
     that: echo.stdout == "555"
+    fail_msg: echo={{echo}}
 
 - file:
     path: /etc/environment
@@ -43,3 +45,4 @@
 
 - assert:
     that: echo.stdout == ""
+    fail_msg: echo={{echo}}
diff --git a/tests/ansible/integration/runner/_etc_environment_user.yml b/tests/ansible/integration/runner/_etc_environment_user.yml
index ca1dc5cc..9d9b831a 100644
--- a/tests/ansible/integration/runner/_etc_environment_user.yml
+++ b/tests/ansible/integration/runner/_etc_environment_user.yml
@@ -9,6 +9,7 @@
 
 - assert:
     that: echo.stdout == ""
+    fail_msg: echo={{echo}}
 
 - copy:
     dest: ~/.pam_environment
@@ -20,6 +21,7 @@
 
 - assert:
     that: echo.stdout == "321"
+    fail_msg: echo={{echo}}
 
 - file:
     path: ~/.pam_environment
@@ -30,3 +32,4 @@
 
 - assert:
     that: echo.stdout == ""
+    fail_msg: echo={{echo}}
diff --git a/tests/ansible/integration/runner/atexit.yml b/tests/ansible/integration/runner/atexit.yml
index 65d27d59..25babf0d 100644
--- a/tests/ansible/integration/runner/atexit.yml
+++ b/tests/ansible/integration/runner/atexit.yml
@@ -29,3 +29,4 @@
     - assert:
         that:
         - not out.stat.exists
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/builtin_command_module.yml b/tests/ansible/integration/runner/builtin_command_module.yml
index 0bc5bd34..b0ca7e1c 100644
--- a/tests/ansible/integration/runner/builtin_command_module.yml
+++ b/tests/ansible/integration/runner/builtin_command_module.yml
@@ -16,3 +16,4 @@
           out.results[0].item == '1' and
           out.results[0].rc == 0 and
           (out.results[0].stdout == ansible_nodename)
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/crashy_new_style_module.yml b/tests/ansible/integration/runner/crashy_new_style_module.yml
index 73bac1f9..3e41fdde 100644
--- a/tests/ansible/integration/runner/crashy_new_style_module.yml
+++ b/tests/ansible/integration/runner/crashy_new_style_module.yml
@@ -23,3 +23,4 @@
         - out.module_stdout == ""
         - "'Traceback (most recent call last)' in out.module_stderr"
         - "\"NameError: name 'kaboom' is not defined\" in out.module_stderr"
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_bash_hashbang_argument.yml b/tests/ansible/integration/runner/custom_bash_hashbang_argument.yml
index f02b8419..1eb79f20 100644
--- a/tests/ansible/integration/runner/custom_bash_hashbang_argument.yml
+++ b/tests/ansible/integration/runner/custom_bash_hashbang_argument.yml
@@ -17,3 +17,4 @@
           (not out.results[0].changed) and
           out.results[0].msg == 'Here is my input' and
           out.results[0].run_via_env == "yes"
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_bash_old_style_module.yml b/tests/ansible/integration/runner/custom_bash_old_style_module.yml
index ff963665..4a14f86e 100644
--- a/tests/ansible/integration/runner/custom_bash_old_style_module.yml
+++ b/tests/ansible/integration/runner/custom_bash_old_style_module.yml
@@ -13,3 +13,4 @@
           (not out.changed) and
           (not out.results[0].changed) and
           out.results[0].msg == 'Here is my input'
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_bash_want_json_module.yml b/tests/ansible/integration/runner/custom_bash_want_json_module.yml
index 075c95b2..5ae74a4d 100644
--- a/tests/ansible/integration/runner/custom_bash_want_json_module.yml
+++ b/tests/ansible/integration/runner/custom_bash_want_json_module.yml
@@ -12,3 +12,4 @@
           (not out.changed) and
           (not out.results[0].changed) and
           out.results[0].msg == 'Here is my input'
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_binary_producing_json.yml b/tests/ansible/integration/runner/custom_binary_producing_json.yml
index a3b8a224..016efac9 100644
--- a/tests/ansible/integration/runner/custom_binary_producing_json.yml
+++ b/tests/ansible/integration/runner/custom_binary_producing_json.yml
@@ -24,3 +24,4 @@
           out.changed and
           out.results[0].changed and
           out.results[0].msg == 'Hello, world.'
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_binary_producing_junk.yml b/tests/ansible/integration/runner/custom_binary_producing_junk.yml
index b9cfb6b4..d302d43c 100644
--- a/tests/ansible/integration/runner/custom_binary_producing_junk.yml
+++ b/tests/ansible/integration/runner/custom_binary_producing_junk.yml
@@ -30,3 +30,4 @@
         - out.results[0].failed
         - out.results[0].msg.startswith('MODULE FAILURE')
         - out.results[0].rc == 0
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_binary_single_null.yml b/tests/ansible/integration/runner/custom_binary_single_null.yml
index ce96bf13..8e2331a2 100644
--- a/tests/ansible/integration/runner/custom_binary_single_null.yml
+++ b/tests/ansible/integration/runner/custom_binary_single_null.yml
@@ -27,6 +27,7 @@
           'custom_binary_single_null: cannot execute binary file: Exec format error\r\n',
         ))
         or (ansible_facts.distribution == 'Ubuntu' and ansible_facts.distribution_version == '16.04')
+      fail_msg: out={{out}}
 
 
 # Can't test this: Mitogen returns 126, 2.5.x returns 126, 2.4.x discarded the
diff --git a/tests/ansible/integration/runner/custom_perl_json_args_module.yml b/tests/ansible/integration/runner/custom_perl_json_args_module.yml
index f705cfe4..9d51e71f 100644
--- a/tests/ansible/integration/runner/custom_perl_json_args_module.yml
+++ b/tests/ansible/integration/runner/custom_perl_json_args_module.yml
@@ -11,9 +11,11 @@
         that:
         - out.results[0].input.foo
         - out.results[0].message == 'I am a perl script! Here is my input.'
+        fail_msg: out={{out}}
 
     - when: ansible_version.full > '2.4'
       assert:
         that:
         - (not out.changed)
         - (not out.results[0].changed)
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_perl_want_json_module.yml b/tests/ansible/integration/runner/custom_perl_want_json_module.yml
index 24527164..57d92fd0 100644
--- a/tests/ansible/integration/runner/custom_perl_want_json_module.yml
+++ b/tests/ansible/integration/runner/custom_perl_want_json_module.yml
@@ -11,9 +11,11 @@
         that:
         - out.results[0].input.foo
         - out.results[0].message == 'I am a want JSON perl script! Here is my input.'
+        fail_msg: out={{out}}
 
     - when: ansible_version.full > '2.4'
       assert:
         that:
         - (not out.changed)
         - (not out.results[0].changed)
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_python_json_args_module.yml b/tests/ansible/integration/runner/custom_python_json_args_module.yml
index 338f9180..5c77097e 100644
--- a/tests/ansible/integration/runner/custom_python_json_args_module.yml
+++ b/tests/ansible/integration/runner/custom_python_json_args_module.yml
@@ -13,3 +13,4 @@
           (not out.results[0].changed) and
           out.results[0].input[0].foo and
           out.results[0].msg == 'Here is my input'
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_python_new_style_missing_interpreter.yml b/tests/ansible/integration/runner/custom_python_new_style_missing_interpreter.yml
index 77f2cb5c..4a375ff0 100644
--- a/tests/ansible/integration/runner/custom_python_new_style_missing_interpreter.yml
+++ b/tests/ansible/integration/runner/custom_python_new_style_missing_interpreter.yml
@@ -15,3 +15,4 @@
         # Random breaking interface change since 2.7.x
         #- "out.results[0].input[0].ANSIBLE_MODULE_ARGS.foo"
         - "out.results[0].msg == 'Here is my input'"
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_python_new_style_module.yml b/tests/ansible/integration/runner/custom_python_new_style_module.yml
index 2ec896b7..3992f4b1 100644
--- a/tests/ansible/integration/runner/custom_python_new_style_module.yml
+++ b/tests/ansible/integration/runner/custom_python_new_style_module.yml
@@ -18,6 +18,7 @@
         # Random breaking interface change since 2.7.x
         #- "out.results[0].input[0].ANSIBLE_MODULE_ARGS.foo"
         - "out.results[0].msg == 'Here is my input'"
+        fail_msg: out={{out}}
 
     # Verify sys.argv is not Unicode.
     - custom_python_detect_environment:
@@ -26,3 +27,4 @@
     - assert:
         that:
           - out.argv_types_correct
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_python_prehistoric_module.yml b/tests/ansible/integration/runner/custom_python_prehistoric_module.yml
index 458f3d2b..19a8a9de 100644
--- a/tests/ansible/integration/runner/custom_python_prehistoric_module.yml
+++ b/tests/ansible/integration/runner/custom_python_prehistoric_module.yml
@@ -7,4 +7,6 @@
     - custom_python_prehistoric_module:
       register: out
 
-    - assert: that=out.ok
+    - assert:
+        that: out.ok
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_python_want_json_module.yml b/tests/ansible/integration/runner/custom_python_want_json_module.yml
index f6d8c355..dd5a5c1c 100644
--- a/tests/ansible/integration/runner/custom_python_want_json_module.yml
+++ b/tests/ansible/integration/runner/custom_python_want_json_module.yml
@@ -13,3 +13,4 @@
           (not out.results[0].changed) and
           out.results[0].input[0].foo and
           out.results[0].msg == 'Here is my input'
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/runner/custom_script_interpreter.yml b/tests/ansible/integration/runner/custom_script_interpreter.yml
index 4c6b3ef5..f496cff0 100644
--- a/tests/ansible/integration/runner/custom_script_interpreter.yml
+++ b/tests/ansible/integration/runner/custom_script_interpreter.yml
@@ -15,4 +15,5 @@
           (not out.changed) and
           (not out.results[0].changed) and
           out.results[0].msg == 'Here is my input'
+        fail_msg: out={{out}}
 
diff --git a/tests/ansible/integration/runner/environment_isolation.yml b/tests/ansible/integration/runner/environment_isolation.yml
index 08f0924f..eee31d6e 100644
--- a/tests/ansible/integration/runner/environment_isolation.yml
+++ b/tests/ansible/integration/runner/environment_isolation.yml
@@ -16,6 +16,7 @@
       register: out
     - assert:
         that: not out.env.evil_key is defined
+        fail_msg: out={{out}}
 
     - shell: echo 'hi'
       environment:
@@ -26,6 +27,7 @@
       register: out
     - assert:
         that: not out.env.evil_key is defined
+        fail_msg: out={{out}}
 
 
     # ---
@@ -37,6 +39,7 @@
       register: out
     - assert:
         that: not out.env.evil_key is defined
+        fail_msg: out={{out}}
 
     - custom_python_modify_environ:
         key: evil_key
@@ -47,4 +50,5 @@
       register: out
     - assert:
         that: not out.env.evil_key is defined
+        fail_msg: out={{out}}
 
diff --git a/tests/ansible/integration/runner/forking_active.yml b/tests/ansible/integration/runner/forking_active.yml
index e3e63b71..ebae849b 100644
--- a/tests/ansible/integration/runner/forking_active.yml
+++ b/tests/ansible/integration/runner/forking_active.yml
@@ -27,5 +27,6 @@
       that:
       - fork_proc1.pid != sync_proc1.pid
       - fork_proc1.pid != fork_proc2.pid
+      fail_msg: fork_proc1={{fork_proc1}} sync_proc1={{sync_proc1}} fork_proc2={{fork_proc2}}
     when: is_mitogen
 
diff --git a/tests/ansible/integration/runner/forking_correct_parent.yml b/tests/ansible/integration/runner/forking_correct_parent.yml
index c70db4e3..59cf48e7 100644
--- a/tests/ansible/integration/runner/forking_correct_parent.yml
+++ b/tests/ansible/integration/runner/forking_correct_parent.yml
@@ -32,12 +32,15 @@
   - assert:
       that:
       - fork_proc.pid != regular_proc.pid
+      fail_msg: fork_proc={{fork_proc}} regular_proc={{regular_proc}}
     when: is_mitogen
 
   - assert:
       that: fork_proc.ppid != regular_proc.pid
+      fail_msg: fork_proc={{fork_proc}} regular_proc={{regular_proc}}
     when: is_mitogen and forkmode.uses_fork
 
   - assert:
       that: fork_proc.ppid == regular_proc.pid
+      fail_msg: fork_proc={{fork_proc}} regular_proc={{regular_proc}}
     when: is_mitogen and not forkmode.uses_fork
diff --git a/tests/ansible/integration/runner/forking_inactive.yml b/tests/ansible/integration/runner/forking_inactive.yml
index b84cec7e..05ec30ef 100644
--- a/tests/ansible/integration/runner/forking_inactive.yml
+++ b/tests/ansible/integration/runner/forking_inactive.yml
@@ -18,6 +18,7 @@
   - assert:
       that:
       - sync_proc1.pid == sync_proc2.pid
+      fail_msg: sync_proc1={{sync_proc1}} sync_proc2={{sync_proc2}}
     when: is_mitogen
 
 
diff --git a/tests/ansible/integration/runner/missing_module.yml b/tests/ansible/integration/runner/missing_module.yml
index 107f5c20..f515b574 100644
--- a/tests/ansible/integration/runner/missing_module.yml
+++ b/tests/ansible/integration/runner/missing_module.yml
@@ -17,3 +17,4 @@
     - assert:
         that: |
           'The module missing_module was not found in configured module paths' in out.stdout
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/ssh/config.yml b/tests/ansible/integration/ssh/config.yml
index 07ad1c21..9cd024e7 100644
--- a/tests/ansible/integration/ssh/config.yml
+++ b/tests/ansible/integration/ssh/config.yml
@@ -17,3 +17,4 @@
           out.result[0].kwargs.identity_file == (
             lookup('env', 'HOME') + '/fakekey'
           )
+        fail_msg: out={{out}}
diff --git a/tests/ansible/integration/ssh/timeouts.yml b/tests/ansible/integration/ssh/timeouts.yml
index 92fd9307..90be6c94 100644
--- a/tests/ansible/integration/ssh/timeouts.yml
+++ b/tests/ansible/integration/ssh/timeouts.yml
@@ -24,4 +24,5 @@
           '"unreachable": true' in out.stdout
         - |
           '"msg": "Connection timed out."' in out.stdout
+        fail_msg: out={{out}}
       when: is_mitogen
diff --git a/tests/ansible/integration/ssh/variables.yml b/tests/ansible/integration/ssh/variables.yml
index 71536391..d05ac288 100644
--- a/tests/ansible/integration/ssh/variables.yml
+++ b/tests/ansible/integration/ssh/variables.yml
@@ -40,6 +40,7 @@
 
     - assert:
         that: out.rc == 4  # unreachable
+        fail_msg: out={{out}}
       when: is_mitogen
 
 
@@ -69,6 +70,7 @@
 
     - assert:
         that: out.rc == 4  # unreachable
+        fail_msg: out={{out}}
       when: is_mitogen
 
 
@@ -98,6 +100,7 @@
 
     - assert:
         that: out.rc == 4  # unreachable
+        fail_msg: out={{out}}
       when: is_mitogen
 
 
@@ -132,4 +135,5 @@
 
     - assert:
         that: out.rc == 4  # unreachable
+        fail_msg: out={{out}}
       when: is_mitogen
diff --git a/tests/ansible/integration/strategy/_mixed_mitogen_vanilla.yml b/tests/ansible/integration/strategy/_mixed_mitogen_vanilla.yml
index 1ec76fd1..3dfec756 100644
--- a/tests/ansible/integration/strategy/_mixed_mitogen_vanilla.yml
+++ b/tests/ansible/integration/strategy/_mixed_mitogen_vanilla.yml
@@ -11,10 +11,12 @@
       register: out
     - assert:
         that: out.mitogen_loaded
+        fail_msg: out={{out}}
 
     - determine_strategy:
     - assert:
         that: strategy == 'ansible.plugins.strategy.mitogen_linear.StrategyModule'
+        fail_msg: strategy={{strategy}}
 
 
 - name: integration/strategy/_mixed_mitogen_vanilla.yml (linear)
@@ -26,10 +28,12 @@
       register: out
     - assert:
         that: not out.mitogen_loaded
+        fail_msg: out={{out}}
 
     - determine_strategy:
     - assert:
         that: strategy == 'ansible.plugins.strategy.linear.StrategyModule'
+        fail_msg: strategy={{strategy}}
 
 
 - name: integration/strategy/_mixed_mitogen_vanilla.yml (mitogen_linear)
@@ -41,7 +45,9 @@
       register: out
     - assert:
         that: out.mitogen_loaded
+        fail_msg: out={{out}}
 
     - determine_strategy:
     - assert:
         that: strategy == 'ansible.plugins.strategy.mitogen_linear.StrategyModule'
+        fail_msg: strategy={{strategy}}
diff --git a/tests/ansible/integration/strategy/_mixed_vanilla_mitogen.yml b/tests/ansible/integration/strategy/_mixed_vanilla_mitogen.yml
index babcab3f..6381f114 100644
--- a/tests/ansible/integration/strategy/_mixed_vanilla_mitogen.yml
+++ b/tests/ansible/integration/strategy/_mixed_vanilla_mitogen.yml
@@ -10,10 +10,12 @@
       register: out
     - assert:
         that: not out.mitogen_loaded
+        fail_msg: out={{out}}
 
     - determine_strategy:
     - assert:
         that: strategy == 'ansible.plugins.strategy.linear.StrategyModule'
+        fail_msg: strategy={{strategy}}
 
 - name: integration/strategy/_mixed_vanilla_mitogen.yml (mitogen_linear)
   hosts: test-targets[0]
@@ -24,10 +26,12 @@
       register: out
     - assert:
         that: out.mitogen_loaded
+        fail_msg: out={{out}}
 
     - determine_strategy:
     - assert:
         that: strategy == 'ansible.plugins.strategy.mitogen_linear.StrategyModule'
+        fail_msg: strategy={{strategy}}
 
 
 - name: integration/strategy/_mixed_vanilla_mitogen.yml (linear)
@@ -39,7 +43,9 @@
       register: out
     - assert:
         that: not out.mitogen_loaded
+        fail_msg: out={{out}}
 
     - determine_strategy:
     - assert:
         that: strategy == 'ansible.plugins.strategy.linear.StrategyModule'
+        fail_msg: strategy={{strategy}}
diff --git a/tests/ansible/integration/stub_connections/kubectl.yml b/tests/ansible/integration/stub_connections/kubectl.yml
index 867a8c17..92ed1a89 100644
--- a/tests/ansible/integration/stub_connections/kubectl.yml
+++ b/tests/ansible/integration/stub_connections/kubectl.yml
@@ -20,3 +20,4 @@
   - assert:
       that:
       - out.env.THIS_IS_STUB_KUBECTL == '1'
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/stub_connections/lxc.yml b/tests/ansible/integration/stub_connections/lxc.yml
index 1dbe2a48..c09f2df2 100644
--- a/tests/ansible/integration/stub_connections/lxc.yml
+++ b/tests/ansible/integration/stub_connections/lxc.yml
@@ -17,3 +17,4 @@
   - assert:
       that:
       - out.env.THIS_IS_STUB_LXC_ATTACH == '1'
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/stub_connections/lxd.yml b/tests/ansible/integration/stub_connections/lxd.yml
index 7839a35f..de7d8766 100644
--- a/tests/ansible/integration/stub_connections/lxd.yml
+++ b/tests/ansible/integration/stub_connections/lxd.yml
@@ -17,3 +17,4 @@
   - assert:
       that:
       - out.env.THIS_IS_STUB_LXC == '1'
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/stub_connections/mitogen_doas.yml b/tests/ansible/integration/stub_connections/mitogen_doas.yml
index 5387744e..4ced049d 100644
--- a/tests/ansible/integration/stub_connections/mitogen_doas.yml
+++ b/tests/ansible/integration/stub_connections/mitogen_doas.yml
@@ -20,3 +20,4 @@
       that:
       - out.env.THIS_IS_STUB_DOAS == '1'
       - (out.env.ORIGINAL_ARGV|from_json)[1:3] == ['-u', 'someuser']
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/stub_connections/mitogen_sudo.yml b/tests/ansible/integration/stub_connections/mitogen_sudo.yml
index e78afebc..2e1b0103 100644
--- a/tests/ansible/integration/stub_connections/mitogen_sudo.yml
+++ b/tests/ansible/integration/stub_connections/mitogen_sudo.yml
@@ -18,6 +18,8 @@
 
   - assert:
       that: out.env.THIS_IS_STUB_SUDO == '1'
+      fail_msg: out={{out}}
+
   - assert_equal:
       left: (out.env.ORIGINAL_ARGV|from_json)[1:9]
       right: ['-u', 'root', '-H', '-r', 'somerole', '-t', 'sometype', '--']
diff --git a/tests/ansible/integration/stub_connections/setns_lxc.yml b/tests/ansible/integration/stub_connections/setns_lxc.yml
index efef3761..fcea3de2 100644
--- a/tests/ansible/integration/stub_connections/setns_lxc.yml
+++ b/tests/ansible/integration/stub_connections/setns_lxc.yml
@@ -31,3 +31,4 @@
 
     - assert:
         that: result.rc == 0
+        fail_msg: result={{result}}
diff --git a/tests/ansible/integration/stub_connections/setns_lxd.yml b/tests/ansible/integration/stub_connections/setns_lxd.yml
index adee0b14..61018382 100644
--- a/tests/ansible/integration/stub_connections/setns_lxd.yml
+++ b/tests/ansible/integration/stub_connections/setns_lxd.yml
@@ -31,3 +31,4 @@
 
     - assert:
         that: result.rc == 0
+        fail_msg: result={{result}}
diff --git a/tests/ansible/integration/transport/kubectl.yml b/tests/ansible/integration/transport/kubectl.yml
index d2be9ba5..4dac2d02 100644
--- a/tests/ansible/integration/transport/kubectl.yml
+++ b/tests/ansible/integration/transport/kubectl.yml
@@ -74,6 +74,7 @@
           register: _
 
         - assert: { that: "'Python 3' in _.stdout" }
+          fail_msg: _={{_}}
 
         - debug: var=_.stdout,_.stderr
           run_once: yes
@@ -83,6 +84,7 @@
           register: _
 
         - assert: { that: "'Python 2' in _.stderr" }
+          fail_msg: _={{_}}
 
         - debug: var=_.stdout,_.stderr
           run_once: yes
@@ -113,7 +115,9 @@
             ansible_kubectl_container: python3
           register: _
 
-        - assert: { that: "'Python 3' in _.stdout" }
+        - assert:
+            that: "'Python 3' in _.stdout"
+            fail_msg: _={{_}}
 
         - debug: var=_.stdout,_.stderr
           run_once: yes
@@ -122,7 +126,9 @@
           command: python --version
           register: _
 
-        - assert: { that: "'Python 2' in _.stderr" }
+        - assert:
+            that: "'Python 2' in _.stderr"
+            fail_msg: _={{_}}
 
         - debug: var=_.stdout,_.stderr
           run_once: yes
diff --git a/tests/ansible/integration/transport_config/become.yml b/tests/ansible/integration/transport_config/become.yml
index baa2085e..51b698eb 100644
--- a/tests/ansible/integration/transport_config/become.yml
+++ b/tests/ansible/integration/transport_config/become.yml
@@ -12,6 +12,7 @@
       - out.result|length == 1
       - out.result[0].method == "ssh"
       - out.result[0].kwargs.username == "ansible-cfg-remote-user"
+      fail_msg: out={{out}}
 
 - hosts: tc-become-unset
   vars: {mitogen_via: becomeuser@tc-become-set}
@@ -29,6 +30,7 @@
 
       - out.result[2].method == "ssh"
       - out.result[2].kwargs.hostname == "tc-become-unset"
+      fail_msg: out={{out}}
 
 
 # Become set.
@@ -46,6 +48,7 @@
       - out.result[0].kwargs.username == "ansible-cfg-remote-user"
       - out.result[1].method == "sudo"
       - out.result[1].kwargs.username == "becomeuser"
+      fail_msg: out={{out}}
 
 - hosts: tc-become-set
   vars: {mitogen_via: tc-become-unset}
@@ -66,3 +69,4 @@
 
       - out.result[2].method == "sudo"
       - out.result[2].kwargs.username == "becomeuser"
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/transport_config/become_method.yml b/tests/ansible/integration/transport_config/become_method.yml
index 5129e5b8..a6eac9ef 100644
--- a/tests/ansible/integration/transport_config/become_method.yml
+++ b/tests/ansible/integration/transport_config/become_method.yml
@@ -13,6 +13,7 @@
       - out.result|length == 2
       - out.result[0].method == "ssh"
       - out.result[1].method == "sudo"
+      fail_msg: out={{out}}
 
 - hosts: tc-become-method-unset
   vars: {mitogen_via: becomeuser@tc-become-method-su}
@@ -27,6 +28,7 @@
       - out.result[1].kwargs.username == "becomeuser"
       - out.result[2].method == "ssh"
       - out.result[2].kwargs.hostname == "tc-become-method-unset"
+      fail_msg: out={{out}}
 
 
 # ansible_become_method=su
@@ -42,6 +44,7 @@
       - out.result[0].method == "ssh"
       - out.result[1].method == "su"
       - out.result[1].kwargs.username == "becomeuser"
+      fail_msg: out={{out}}
 
 - hosts: tc-become-method-su
   vars: {mitogen_via: tc-become-method-unset}
@@ -61,6 +64,7 @@
 
       - out.result[2].method == "su"
       - out.result[2].kwargs.username == "becomeuser"
+      fail_msg: out={{out}}
 
 
 
@@ -81,3 +85,4 @@
 
       - out.result[2].method == "ssh"
       - out.result[2].kwargs.hostname == "tc-become-method-unset"
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/transport_config/become_pass.yml b/tests/ansible/integration/transport_config/become_pass.yml
index 6a2188b1..6287e708 100644
--- a/tests/ansible/integration/transport_config/become_pass.yml
+++ b/tests/ansible/integration/transport_config/become_pass.yml
@@ -14,6 +14,7 @@
       - out.result[0].method == "ssh"
       - out.result[1].method == "sudo"
       - out.result[1].kwargs.password == None
+      fail_msg: out={{out}}
 
 # Not set, unbecoming mitogen_via=
 - hosts: tc-become-pass-unset
@@ -29,6 +30,7 @@
       - out.result[1].method == "ssh"
       - out.result[2].method == "sudo"
       - out.result[2].kwargs.password == None
+      fail_msg: out={{out}}
 
 # Not set, becoming mitogen_via=
 - hosts: tc-become-pass-unset
@@ -46,6 +48,7 @@
       - out.result[2].method == "ssh"
       - out.result[3].method == "sudo"
       - out.result[3].kwargs.password == None
+      fail_msg: out={{out}}
 
 
 # ansible_become_password= set.
@@ -60,6 +63,7 @@
       - out.result[0].method == "ssh"
       - out.result[1].method == "sudo"
       - out.result[1].kwargs.password == "apassword"
+      fail_msg: out={{out}}
 
 
 # ansible_become_password=, via=
@@ -78,6 +82,7 @@
       - out.result[2].method == "ssh"
       - out.result[3].method == "sudo"
       - out.result[3].kwargs.password == "apassword"
+      fail_msg: out={{out}}
 
 
 # ansible_become_pass=
@@ -92,6 +97,7 @@
       - out.result[0].method == "ssh"
       - out.result[1].method == "sudo"
       - out.result[1].kwargs.password == "apass"
+      fail_msg: out={{out}}
 
 
 # ansible_become_pass=, via=
@@ -110,6 +116,7 @@
       - out.result[2].method == "ssh"
       - out.result[3].method == "sudo"
       - out.result[3].kwargs.password == "apass"
+      fail_msg: out={{out}}
 
 
 
@@ -126,6 +133,7 @@
       - out.result[0].method == "ssh"
       - out.result[1].method == "sudo"
       - out.result[1].kwargs.password == "c.b.a"
+      fail_msg: out={{out}}
 
 
 # both, mitogen_via
@@ -141,3 +149,4 @@
       - out.result[1].method == "sudo"
       - out.result[1].kwargs.password == "a.b.c"
       - out.result[2].method == "ssh"
+      fail_msg: out={{out}}
diff --git a/tests/ansible/integration/transport_config/become_user.yml b/tests/ansible/integration/transport_config/become_user.yml
index 43cbca2a..3c8397ad 100644
--- a/tests/ansible/integration/transport_config/become_user.yml
+++ b/tests/ansible/integration/transport_config/become_user.yml
@@ -14,6 +14,7 @@
       - out.result[0].method == "ssh"
       - out.result[1].method == "sudo"
       - out.result[1].kwargs.username == "root"
+      fail_msg: out={{out}}
 
 # Not set, unbecoming mitogen_via=
 - hosts: tc-become-user-unset
@@ -29,6 +30,7 @@
       - out.result[1].method == "ssh"
       - out.result[2].method == "sudo"
       - out.result[2].kwargs.username == "root"
+      fail_msg: out={{out}}
 
 # Not set, becoming mitogen_via=
 - hosts: tc-become-user-unset
@@ -46,6 +48,7 @@
       - out.result[2].method == "ssh"
       - out.result[3].method == "sudo"
       - out.result[3].kwargs.username == "root"
+      fail_msg: out={{out}}
 
 
 # ansible_become_user= set.
@@ -60,6 +63,7 @@
       - out.result[0].method == "ssh"
       - out.result[1].method == "sudo"
       - out.result[1].kwargs.username == "ansi-become-user"
+      fail_msg: out={{out}}
 
 
 # ansible_become_user=, unbecoming via=
@@ -80,6 +84,7 @@
 
       - out.result[2].method == "sudo"
       - out.result[2].kwargs.username == "ansi-become-user"
+      fail_msg: out={{out}}
 
 
 # ansible_become_user=, becoming via=
@@ -103,4 +108,5 @@
 
       - out.result[3].method == "sudo"
       - out.result[3].kwargs.username == "ansi-become-user"
+      fail_msg: out={{out}}
 
diff --git a/tests/ansible/integration/transport_config/port.yml b/tests/ansible/integration/transport_config/port.yml
index 2781081a..6014ffae 100644
--- a/tests/ansible/integration/transport_config/port.yml
+++ b/tests/ansible/integration/transport_config/port.yml
@@ -12,6 +12,7 @@
       - out.result|length == 1
       - out.result[0].method == "ssh"
       - out.result[0].kwargs.port == None
+      fail_msg: out={{out}}
 
 # Not set, mitogen_via=
 - hosts: tc-port-explicit-ssh
@@ -26,6 +27,7 @@
       - out.result[0].kwargs.port == None
       - out.result[1].method == "ssh"
       - out.result[1].kwargs.port == 4321
+      fail_msg: out={{out}}
 
 # ansible_ssh_port=
 - hosts: tc-port-explicit-ssh
@@ -37,6 +39,7 @@
       - out.result|length == 1
       - out.result[0].method == "ssh"
       - out.result[0].kwargs.port == 4321
+      fail_msg: out={{out}}
 
 - hosts: tc-port-explicit-unset
   vars: {mitogen_via: tc-port-explicit-ssh}
@@ -50,6 +53,7 @@
       - out.result[1].kwargs.port == 4321
       - out.result[1].method == "ssh"
       - out.result[0].kwargs.port == None
+      fail_msg: out={{out}}
 
 # ansible_port=
 - hosts: tc-port-explicit-port
@@ -61,6 +65,7 @@
       - out.result|length == 1
       - out.result[0].method == "ssh"
       - out.result[0].kwargs.port == 1234
+      fail_msg: out={{out}}
 
 - hosts: tc-port-unset
   vars: {mitogen_via: tc-port-explicit-port}
@@ -74,6 +79,7 @@
       - out.result[0].kwargs.port == 1234
       - out.result[1].method == "ssh"
       - out.result[1].kwargs.port == None
+      fail_msg: out={{out}}
 
 
 # both, ssh takes precedence
@@ -86,6 +92,7 @@
       - out.result|length == 1
       - out.result[0].method == "ssh"
       - out.result[0].kwargs.port == 1532
+      fail_msg: out={{out}}
 
 - hosts: tc-port-unset
   vars: {mitogen_via: tc-port-both}
@@ -99,3 +106,4 @@
       - out.result[0].kwargs.port == 1532
       - out.result[1].method == "ssh"
       - out.result[1].kwargs.port == None
+      fail_msg: out={{out}}
diff --git a/tests/ansible/regression/issue_109__target_has_old_ansible_installed.yml b/tests/ansible/regression/issue_109__target_has_old_ansible_installed.yml
index 75e2598a..5c00734f 100644
--- a/tests/ansible/regression/issue_109__target_has_old_ansible_installed.yml
+++ b/tests/ansible/regression/issue_109__target_has_old_ansible_installed.yml
@@ -25,6 +25,7 @@
         that:
           - env.cwd == ansible_user_dir
           - (not env.mitogen_loaded) or (env.python_path.count("") == 1)
+        fail_msg: env={{env}}
 
     # Run some new-style modules that 'from ansible.module_utils...'
     - stat:
diff --git a/tests/ansible/regression/issue_113__duplicate_module_imports.yml b/tests/ansible/regression/issue_113__duplicate_module_imports.yml
index 2b9e3ea8..7c556588 100644
--- a/tests/ansible/regression/issue_113__duplicate_module_imports.yml
+++ b/tests/ansible/regression/issue_113__duplicate_module_imports.yml
@@ -21,4 +21,5 @@
       that:
         - out.status == -1
         - out.url == 'http://127.0.0.1:14321/post'
+      fail_msg: out={{out}}
 
diff --git a/tests/ansible/regression/issue_152__local_action_wrong_interpreter.yml b/tests/ansible/regression/issue_152__local_action_wrong_interpreter.yml
index 8a8f0068..104e27cc 100644
--- a/tests/ansible/regression/issue_152__local_action_wrong_interpreter.yml
+++ b/tests/ansible/regression/issue_152__local_action_wrong_interpreter.yml
@@ -25,6 +25,7 @@
     - assert:
         that:
           - out.env.CUSTOM_INTERPRETER == "1"
+        fail_msg: out={{out}}
 
     - file:
         path: /tmp/issue_152_interpreter.sh
diff --git a/tests/ansible/regression/issue_152__virtualenv_python_fails.yml b/tests/ansible/regression/issue_152__virtualenv_python_fails.yml
index 6df3df12..c04f0b80 100644
--- a/tests/ansible/regression/issue_152__virtualenv_python_fails.yml
+++ b/tests/ansible/regression/issue_152__virtualenv_python_fails.yml
@@ -24,6 +24,7 @@
     - assert:
         that:
           - out.sys_executable == "/tmp/issue_152_virtualenv/bin/python"
+        fail_msg: out={{out}}
       when: lout.python_version > '2.6'
 
     - file:
diff --git a/tests/ansible/regression/issue_154__module_state_leaks.yml b/tests/ansible/regression/issue_154__module_state_leaks.yml
index faef6e63..b25b9030 100644
--- a/tests/ansible/regression/issue_154__module_state_leaks.yml
+++ b/tests/ansible/regression/issue_154__module_state_leaks.yml
@@ -15,4 +15,5 @@
       that:
         - out.results[item|int].leak1 == ["David"]
         - out.results[item|int].leak2 == ["David"]
+      fail_msg: out={{out}}
     with_sequence: start=0 end=3
diff --git a/tests/ansible/regression/issue_332_ansiblemoduleerror_first_occurrence.yml b/tests/ansible/regression/issue_332_ansiblemoduleerror_first_occurrence.yml
index 6f32af19..4138b544 100644
--- a/tests/ansible/regression/issue_332_ansiblemoduleerror_first_occurrence.yml
+++ b/tests/ansible/regression/issue_332_ansiblemoduleerror_first_occurrence.yml
@@ -11,3 +11,4 @@
   - assert:
       that:
         - out.msg == 'file (/usr/bin/does-not-exist) is absent, cannot continue'
+      fail_msg: out={{out}}
diff --git a/tests/ansible/regression/issue_590__sys_modules_crap.yml b/tests/ansible/regression/issue_590__sys_modules_crap.yml
index 41130b68..486b6d31 100644
--- a/tests/ansible/regression/issue_590__sys_modules_crap.yml
+++ b/tests/ansible/regression/issue_590__sys_modules_crap.yml
@@ -10,3 +10,4 @@
   - assert:
       that:
       - "'id' in out.info"
+      fail_msg: out={{out}}