diff --git a/README.md b/README.md
index 75c5153..03ea64f 100644
--- a/README.md
+++ b/README.md
@@ -7,9 +7,13 @@ Tests are executed using TMT (Test Management Tool). The repository includes a
 TMT plan that runs all the tests by default. All the tests support the following
 context dimensions:
 
-* `distro`
-* `arch`
-* `collection` (only applicable to RHEL 7)
+* `distro`: The distribution version running the tests (e.g. `rhel-9.6`,
+  `fedora-42`, `centos-stream-10`)
+* `arch`: The hardware architecture of the host running the tests (e.g. `aarch64`,
+`s390x`, `x86_64`)
+* `compat`: Indicates a run for fedora compat-versioned packages (e.g. `llvm18`)
+* `snapshot`: Indicates a run for [llvm snapshots](
+  https://github.com/fedora-llvm-team/llvm-snapshots) copr build.
 
 To run the tests:
 ```bash
@@ -93,6 +97,18 @@ tier: 1
 #   - sometag
 ```
 
+### Test Tags
+
+The following tags are used to control which tests are included or excluded in
+TMT plans. Please be cautious when adding or removing these tags, as they are
+used by plans in multiple repositories.
+
+* `fedora-only`: The test applies to Fedora distros only.
+* `not-in-default`: Excludes the test from the default test plan. This is useful
+  for resource-intensive tests that are better suited for a dedicated test plan
+  or could potentially break the test system.
+* `multilib`: Requires 32-bit (i686) package dependencies.
+
 ### Avoid common errors using pre-commit
 
 This project uses [`pre-commit`](https://pre-commit.com/)
diff --git a/plans/build-gating-alternatives.fmf b/plans/build-gating-alternatives.fmf
index 3264a70..d4dda12 100644
--- a/plans/build-gating-alternatives.fmf
+++ b/plans/build-gating-alternatives.fmf
@@ -26,10 +26,6 @@ adjust+:
 
   - because: lld is not shipped in s390x on LLVM < 18
     enabled: false
-    when: arch == s390x and distro < rhel-8.10, fedora-40, centos-stream-9
+    when: arch == s390x and distro ~< rhel-8.10
   - enabled: false
-    when: arch == s390x and distro == rhel-9 and distro < rhel-9.5
-
-  - because: lld is not shipped for ppc64
-    enabled: false
-    when: arch == ppc64
+    when: arch == s390x and distro ~< rhel-9.5
diff --git a/plans/build-gating.fmf b/plans/build-gating.fmf
index 09ae36d..f3e801c 100644
--- a/plans/build-gating.fmf
+++ b/plans/build-gating.fmf
@@ -38,7 +38,7 @@ adjust:
 discover:
     - name: llvm-tests
       how: fmf
-      filter: "tag:-spoils-installation & tag:-not-in-default"
+      filter: "tag:-not-in-default"
 execute:
     how: tmt
 provision:
diff --git a/tests/abi-test-suite/main.fmf b/tests/abi-test-suite/main.fmf
index aa2eaa5..7f8c442 100644
--- a/tests/abi-test-suite/main.fmf
+++ b/tests/abi-test-suite/main.fmf
@@ -1,6 +1,9 @@
 summary: Run ABI tests from llvm-test-suite package
 duration: 1h
 
+tag+:
+  - fedora-only
+
 adjust+:
   - because: "llvm-test-suite is available for Fedora, not RHEL/CentOS"
     when: >-
diff --git a/tests/bolt-sanity/main.fmf b/tests/bolt-sanity/main.fmf
index a4e69e8..5637470 100644
--- a/tests/bolt-sanity/main.fmf
+++ b/tests/bolt-sanity/main.fmf
@@ -1,6 +1,9 @@
 summary: Sanity check that llvm-bolt works
 tier: 1
 
+tag+:
+  - fedora-only
+
 adjust+:
   - because: "llvm-bolt is available for Fedora, not RHEL/CentOS"
     when: distro != fedora
diff --git a/tests/broken-symlinks/main.fmf b/tests/broken-symlinks/main.fmf
index ddb3fe5..44b0978 100644
--- a/tests/broken-symlinks/main.fmf
+++ b/tests/broken-symlinks/main.fmf
@@ -14,10 +14,4 @@ adjust+:
   # There are no plans to backport that, so we disable the test
   # in distros where LLVM < 17.
   - enabled: false
-    when: distro < rhel-8
-  - enabled: false
-    when: distro == rhel-8 and distro <= rhel-8.9
-  - enabled: false
-    when: distro == rhel-9 and distro <= rhel-9.3
-  - enabled: false
-    when: distro == fedora and distro <= fedora-38
+    when: distro ~<= rhel-9.3
diff --git a/tests/clang-format-diff/main.fmf b/tests/clang-format-diff/main.fmf
index 79cb086..87f15c5 100644
--- a/tests/clang-format-diff/main.fmf
+++ b/tests/clang-format-diff/main.fmf
@@ -1,5 +1,8 @@
 summary: clang-format-diff
 tier: 1
 
+link+:
+  verifies: https://bugzilla.redhat.com/show_bug.cgi?id=1939018
+
 require+:
   - clang-tools-extra
diff --git a/tests/cross-compile-i686/main.fmf b/tests/cross-compile-i686/main.fmf
index c384848..ea915ec 100644
--- a/tests/cross-compile-i686/main.fmf
+++ b/tests/cross-compile-i686/main.fmf
@@ -4,6 +4,10 @@ description: >
   proper directory
 tier: 1
 
+tag+:
+  - multilib
+  - fedora-only
+
 require+:
   - compiler-rt.i686
   - glibc-devel.i686
diff --git a/tests/fedora-flags/main.fmf b/tests/fedora-flags/main.fmf
index 436049d..16a0b0a 100644
--- a/tests/fedora-flags/main.fmf
+++ b/tests/fedora-flags/main.fmf
@@ -1,17 +1,5 @@
 summary: fedora-flags
+description: Build sample C/C++ code with default system flags from redhat-rpm-config
 require+:
   - redhat-rpm-config
 tier: 1
-
-adjust+:
-  - because: s390x does not have epel repo which is required to provide rpm macros
-    enabled: false
-    when: >-
-      distro == rhel-7
-      and arch == s390x
-
-  # Note: this needs epel-release repo to be available
-  - because: "To enable rpm macros not available by default (e.g. build_cflags), epel-rpm-macros is needed"
-    require+:
-      - epel-rpm-macros
-    when: distro == rhel-7
diff --git a/tests/find-package-llvm/main.fmf b/tests/find-package-llvm/main.fmf
index bb6be98..e39c326 100644
--- a/tests/find-package-llvm/main.fmf
+++ b/tests/find-package-llvm/main.fmf
@@ -20,3 +20,8 @@ require+:
   - llvm-devel
   - clang
   - clang-devel
+
+adjust+:
+  - enabled: false
+    when: deploymentmode == image
+    because: "/usr is readonly in imagemode systems"
diff --git a/tests/integration-test-suite/rhel.fmf b/tests/integration-test-suite/rhel.fmf
index 1753bf2..229b698 100644
--- a/tests/integration-test-suite/rhel.fmf
+++ b/tests/integration-test-suite/rhel.fmf
@@ -27,15 +27,15 @@ adjust+:
   # a way to provide custom contexts, we need to filter out by distro versions.
   - require-:
       - lld
-    when: arch == s390x and distro < rhel-8.10, centos-stream-9
+    when: arch == s390x and distro < rhel-8.10
   - require-:
       - lld
-    when: arch == s390x and distro == rhel-9 and distro < rhel-9.5
+    when: arch == s390x and distro ~< rhel-9.5
 
-  # libomp is not supported in s390x in RHEL.
+  # libomp is not supported in s390x in RHEL... Until LLVM 19
   - require-:
       - libomp-devel
-    when: arch == s390x
+    when: arch == s390x and distro ~< rhel-9.6.0
 
   # RHEL 8 use python3.12
   - require-:
diff --git a/tests/kernel-ark-build/main.fmf b/tests/kernel-ark-build/main.fmf
index 149eca2..b1c5561 100644
--- a/tests/kernel-ark-build/main.fmf
+++ b/tests/kernel-ark-build/main.fmf
@@ -24,6 +24,7 @@ link+:
   - verifies: https://issues.redhat.com/browse/LLVM-72
 tag+:
   - not-in-default
+  - fedora-only
 
 /base:
   summary+: " (base/non-LTO)"
diff --git a/tests/libomp/main.fmf b/tests/libomp/main.fmf
index c503044..21a37fd 100644
--- a/tests/libomp/main.fmf
+++ b/tests/libomp/main.fmf
@@ -12,17 +12,9 @@ require+:
 
 adjust+:
   # Right now libomp in s390x is supported only in LLVM >= 18 in Fedora
+  # And in LLVM >= 19 in CentOS/RHEL
   # TODO until tmt allows to use custom adjusted contexts we need to do this
   # indirect adjustment using the distro version.
-  - when: arch == s390x and distro < fedora-40 and snapshot is not defined
+  - when: arch == s390x and distro ~< rhel-9.6.0
     enabled: false
     continue: false
-
-  - when: arch == s390x and distro != fedora
-    enabled: false
-    continue: false
-
-  # Dependencies in rhel-7 are handled differently: there are no recommends,
-  # only requires.
-  - when: distro <= rhel-7
-    enabled: false
diff --git a/tests/lld/gcc-compat-basic/main.fmf b/tests/lld/gcc-compat-basic/main.fmf
index 2cd3a2b..2d79ca3 100644
--- a/tests/lld/gcc-compat-basic/main.fmf
+++ b/tests/lld/gcc-compat-basic/main.fmf
@@ -2,8 +2,3 @@ summary: Test lld with gcc
 require+:
   - gcc
 tier: 1
-
-adjust+:
-  - because: system gcc is too old in rhel-7
-    enabled: false
-    when: distro <= rhel-7
diff --git a/tests/lld/ld-alternative/main.fmf b/tests/lld/ld-alternative/main.fmf
index 83d4f8f..7c3da93 100644
--- a/tests/lld/ld-alternative/main.fmf
+++ b/tests/lld/ld-alternative/main.fmf
@@ -1,7 +1,7 @@
 summary: Test linker switching with alternatives
-# This test spoils the installation by removing lld, therefore it should be marked as such.
+# This test spoils the installation by removing lld.
 tag+:
-  - spoils-installation
+  - not-in-default
 require+:
   - binutils
 tier: 1
diff --git a/tests/lld/main.fmf b/tests/lld/main.fmf
index 823bb7a..a3f50ad 100644
--- a/tests/lld/main.fmf
+++ b/tests/lld/main.fmf
@@ -3,12 +3,8 @@ require+:
   - lld
 
 adjust+:
-  - because: lld is not shipped for ppc64
-    enabled: false
-    when: arch == ppc64
-
   - because: lld is not shipped in s390x on LLVM < 18
     enabled: false
-    when: arch == s390x and distro < rhel-8.10, fedora-40, centos-stream-9
+    when: arch == s390x and distro < rhel-8.10
   - enabled: false
-    when: arch == s390x and distro == rhel-9 and distro < rhel-9.5
+    when: arch == s390x and distro ~< rhel-9.5
diff --git a/tests/llvm-test-suite/main.fmf b/tests/llvm-test-suite/main.fmf
index d4d005a..a665eb9 100644
--- a/tests/llvm-test-suite/main.fmf
+++ b/tests/llvm-test-suite/main.fmf
@@ -1,6 +1,8 @@
-# TODO: once llvm-test-suite is converted to TMT, we can just link the test from plan.
 summary: Run tests from llvm-test-suite package
 
+tag+:
+  - fedora-only
+
 adjust+:
   - because: "llvm-test-suite is available for Fedora, not RHEL/CentOS"
     when: >-
diff --git a/tests/multilib-install/main.fmf b/tests/multilib-install/main.fmf
index d57b079..3cc2cdd 100644
--- a/tests/multilib-install/main.fmf
+++ b/tests/multilib-install/main.fmf
@@ -1,6 +1,9 @@
 summary: Make sure that multilib installation works
 tier: 1
 
+tag+:
+  - multilib
+
 require+:
   - llvm-devel
   - llvm-devel.i686
diff --git a/tests/openmp-rpm/main.fmf b/tests/openmp-rpm/main.fmf
index bbe6346..69674a4 100644
--- a/tests/openmp-rpm/main.fmf
+++ b/tests/openmp-rpm/main.fmf
@@ -8,12 +8,9 @@ component+:
 
 adjust+:
   # Right now libomp in s390x is supported only in LLVM >= 18 in Fedora
+  # And in LLVM >= 19 in CentOS/RHEL
   # TODO until tmt allows to use custom adjusted contexts we need to do this
   # indirect adjustment using the distro version.
-  - when: arch == s390x and distro < fedora-40 and snapshot is not defined
-    enabled: false
-    continue: false
-
-  - when: arch == s390x and distro != fedora
+  - when: arch == s390x and distro ~< rhel-9.6.0
     enabled: false
     continue: false
diff --git a/tests/rhbz_482491/main.fmf b/tests/rhbz_1482491/main.fmf
similarity index 93%
rename from tests/rhbz_482491/main.fmf
rename to tests/rhbz_1482491/main.fmf
index c0d524b..bc67898 100644
--- a/tests/rhbz_482491/main.fmf
+++ b/tests/rhbz_1482491/main.fmf
@@ -1,4 +1,4 @@
-summary: rhbz-482491
+summary: rhbz-1482491
 description: |
   "Test that clang is able to find the right libgcc_s"
 require+:
diff --git a/tests/rhbz_482491/test.sh b/tests/rhbz_1482491/test.sh
similarity index 100%
rename from tests/rhbz_482491/test.sh
rename to tests/rhbz_1482491/test.sh
diff --git a/tests/rhbz_1647130/main.fmf b/tests/rhbz_1647130/main.fmf
index 921251e..a8cf420 100644
--- a/tests/rhbz_1647130/main.fmf
+++ b/tests/rhbz_1647130/main.fmf
@@ -1,4 +1,5 @@
 summary: RHBZ1647130
+description: Test that scan-build and scan-view can run without aborting
 tier: 1
 
 require+:
diff --git a/tests/rhbz_1657544/main.fmf b/tests/rhbz_1657544/main.fmf
index 2aabac2..074daa5 100644
--- a/tests/rhbz_1657544/main.fmf
+++ b/tests/rhbz_1657544/main.fmf
@@ -1,2 +1,7 @@
 summary: RHBZ1657544
+description: |
+  Test that clang++ does not use the symbol __muloti4
 tier: 1
+
+link+:
+  resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1657544
diff --git a/tests/rhbz_2239619/main.fmf b/tests/rhbz_2239619/main.fmf
index dd5c972..f406092 100644
--- a/tests/rhbz_2239619/main.fmf
+++ b/tests/rhbz_2239619/main.fmf
@@ -1,2 +1,5 @@
 summary: Test if debug information is disabled by default
 tier: 1
+
+link+:
+  verifies: https://bugzilla.redhat.com/show_bug.cgi?id=2239619
diff --git a/tests/toolchains/main.fmf b/tests/toolchains/main.fmf
index 72fc4d8..dc38125 100644
--- a/tests/toolchains/main.fmf
+++ b/tests/toolchains/main.fmf
@@ -13,17 +13,7 @@ adjust+:
     # requirements, remove it.
   - require-:
       - lld
-    when: >-
-      arch == s390x and distro < rhel-9, rhel-9.5, fedora-40, centos-stream-9
-      or arch == ppc64
-
-  # LLVM is getting updated to 18 in rhel 8.10 which adds lld for s390x, but we
-  # still have LLVM 17 in AppStream. Install lld if it's available, leave it out
-  # if not. The test will (correctly) fail if we lld is missing in LLVM 18.
-  # TODO once LLVM 18 is in the default module stream we can set this a require:
-  - recommend+:
-      - lld
-    when: arch == s390x and distro == rhel-8.10
+    when: arch == s390x and distro ~< rhel-9.5
 
   - environment+:
       CXXLIBS: "libc++"
@@ -37,9 +27,7 @@ adjust+:
       CXXLIBS: "libstdc++"
     require+:
       - libstdc++
-    when: >-
-      distro == rhel
-      or distro == centos
+    when: distro == rhel, centos
     because: testing against libstdc++ package in RHEL as libcxx is not shipped with RHEL
 
   # llvm-snapshots specific adjustments.
@@ -58,7 +46,3 @@ adjust+:
       - lld
     when: snapshot is defined
     because: llvm-snapshots adjustments
-
-
-# TODO REVIEW: are these all requirements? test.sh seems to run quite a lot of stuff, looks like we
-# need more packages from LLVM family.
diff --git a/tests/ucrt64-toolchain/main.fmf b/tests/ucrt64-toolchain/main.fmf
index 18c9f22..2e5e4d2 100644
--- a/tests/ucrt64-toolchain/main.fmf
+++ b/tests/ucrt64-toolchain/main.fmf
@@ -2,7 +2,13 @@ summary: Test that ucrt64 toolchain is detected
 require+:
   - ucrt64-gcc-c++
 
+tag+:
+  - fedora-only
+
+link+:
+  - verifies: https://bugzilla.redhat.com/show_bug.cgi?id=2152220
+
 adjust+:
   - enabled: false
-    when: distro != fedora or distro < fedora-37
-    because: "The ucrt64 toolchain is only available since Fedora 37"
+    when: distro != fedora
+    because: "The ucrt64 toolchain is only available in Fedora"
diff --git a/tests/zstd-support/main.fmf b/tests/zstd-support/main.fmf
index 519afc4..2d92c29 100644
--- a/tests/zstd-support/main.fmf
+++ b/tests/zstd-support/main.fmf
@@ -5,9 +5,7 @@ framework: beakerlib
 require+:
   - lld
 adjust+:
-  - when: distro == fedora and distro < fedora-41 or
-      distro == rhel-8 and distro < rhel-8.10 or
-      distro == rhel-9 and distro < rhel-9.6
+  - when: distro ~< rhel-8.10, rhel-9.6
     enabled: false
     because: ZSTD is enabled only in LLVM 19 and newer
 link+: