diff --git a/master_changes.md b/master_changes.md
index 6a2b0505cb8..20ee3bdb852 100644
--- a/master_changes.md
+++ b/master_changes.md
@@ -54,6 +54,7 @@ users)
   * [BUG] Prevent `.changes` files from being updated during dry-run [#5144 @na4zagin3 - fix #5132]
   * Log a summary of recorded `.changes` as a `ACTION` trace log to help debug #4419 [#5144 @na4zagin3]
   * ◈ Add `--with-tools` option to install recommended development tools from opam file (as `with-test`/`with-doc`), and its environment variable `OPAMWITHTOOLS` [#5016 @rjbou]
+    * Resolve `with-tools` for post messages too [#5160 @rjbou]
 
 ## Remove
   *
@@ -310,6 +311,7 @@ users)
   * Add test for opam file write with format preserved bug in #4936, fixed in #4941 [#4159 @rjbou]
   * Add test for switch upgrade from 2.0 root, with pinned compiler [#5176 @rjbou @kit-ty-kate]
   * Add switch import (for pinned packages) test [#5181 @rjbou]
+  * Add `--with-tools` test [#5160 @rjbou]
 ### Engine
   * Add `opam-cat` to normalise opam file printing [#4763 @rjbou @dra27] [2.1.0~rc2 #4715]
   * Fix meld reftest: open only with failing ones [#4913 @rjbou]
diff --git a/src/client/opamSolution.ml b/src/client/opamSolution.ml
index c9613e59829..0d88677086d 100644
--- a/src/client/opamSolution.ml
+++ b/src/client/opamSolution.ml
@@ -38,6 +38,10 @@ let post_message ?(failed=false) st action =
       OpamVariable.Map.add (OpamVariable.of_string "failure")
         (Some (B failed)) local_variables
     in
+    let local_variables =
+      OpamVariable.Map.add (OpamVariable.of_string "with-tools")
+        (Some (B OpamStateConfig.(!r.with_tools))) local_variables
+    in
     let messages =
       let filter_env = OpamPackageVar.resolve ~opam ~local:local_variables st in
       (if OpamFile.OPAM.has_flag Pkgflag_Deprecated opam then
diff --git a/tests/reftests/dune.inc b/tests/reftests/dune.inc
index 7c2b726d817..f49044cad9a 100644
--- a/tests/reftests/dune.inc
+++ b/tests/reftests/dune.inc
@@ -909,6 +909,23 @@
    %{targets}
    (run ./run.exe %{bin:opam} %{dep:var-option.test} %{read-lines:testing-env}))))
 
+(rule
+ (alias reftest-with-tools)
+ (action
+  (diff with-tools.test with-tools.out)))
+
+(alias
+ (name reftest)
+ (deps (alias reftest-with-tools)))
+
+(rule
+ (targets with-tools.out)
+ (deps root-N0REP0)
+ (action
+  (with-stdout-to
+   %{targets}
+   (run ./run.exe %{bin:opam} %{dep:with-tools.test} %{read-lines:testing-env}))))
+
 (rule
  (alias reftest-working-dir)
  (action
diff --git a/tests/reftests/with-tools.test b/tests/reftests/with-tools.test
new file mode 100644
index 00000000000..4b9d3056e5c
--- /dev/null
+++ b/tests/reftests/with-tools.test
@@ -0,0 +1,58 @@
+N0REP0
+### <pkg:a.1>
+opam-version: "2.0"
+depends: [ "b" "tool" {with-tools} ]
+build: [ [ "touch" "one" ] [ "touch" "two" ] {with-tools} ]
+install: [ [ "cp" "one" "%{lib}%" ] [ "cp" "two" "%{lib}%" ] {with-tools} ]
+post-messages:
+[ "Thanks for installing the packages"
+  "and its tool dependencies too" {with-tools} ]
+### <pkg:b.1>
+opam-version: "2.0"
+### <pkg:tool.1>
+opam-version: "2.0"
+### OPAMYES=1
+### opam switch create tooling --empty
+### opam install a
+The following actions will be performed:
+=== install 2 packages
+  - install a 1
+  - install b 1 [required by a]
+
+<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
+-> installed b.1
+-> installed a.1
+Done.
+
+<><> a.1 installed successfully <><><><><><><><><><><><><><><><><><><><><><><><>
+=> Thanks for installing the packages
+### opam list a --column=installed-files
+# Packages matching: name-match(a) & (installed | available)
+# Installed files
+${BASEDIR}/OPAM/tooling/lib/one
+### opam remove a
+The following actions will be performed:
+=== remove 1 package
+  - remove a 1
+
+<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
+-> removed   a.1
+Done.
+### opam install a --with-tools
+The following actions will be performed:
+=== install 2 packages
+  - install a    1
+  - install tool 1 [required by a]
+
+<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
+-> installed tool.1
+-> installed a.1
+Done.
+
+<><> a.1 installed successfully <><><><><><><><><><><><><><><><><><><><><><><><>
+=> Thanks for installing the packages
+=> and its tool dependencies too
+### opam list a --column=installed-files
+# Packages matching: name-match(a) & (installed | available)
+# Installed files
+${BASEDIR}/OPAM/tooling/lib/one ${BASEDIR}/OPAM/tooling/lib/two