diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a99cedf..ae5755a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -44,14 +44,19 @@ jobs:
       fail-fast: false
       matrix:
         env-paths:
-          - ["envs/env1.yaml"]
-          - ["envs/env2.yaml"]
-          - ["envs/env1.yaml", "envs/env2.yaml"]
+          - "envs/env1.yaml"
+          - "envs/env2.yaml"
+          - |
+            envs/env1.yaml
+            envs/env2.yaml
         expected-failure: ["false"]
         include:
-          - env-paths: ["envs/failing-env1.yaml"]
+          - env-paths: |
+              envs/failing-env1.yaml
             expected-failure: "true"
-          - env-paths: ["envs/env1.yaml", "envs/failing-env1.yaml"]
+          - env-paths: |
+              envs/env1.yaml
+              envs/failing-env1.yaml
             expected-failure: "true"
 
     steps:
@@ -62,7 +67,7 @@ jobs:
         id: action-run
         continue-on-error: true
         with:
-          environment-paths: "${{ toJSON(matrix.env-paths) }}"
+          environment-paths: ${{ matrix.env-paths }}
       - name: detect outcome
         if: always()
         shell: bash -l {0}
diff --git a/README.md b/README.md
index 3b480a5..0939659 100644
--- a/README.md
+++ b/README.md
@@ -10,8 +10,26 @@ To use the `minimum-dependency-versions` action in workflows, simply add a new s
 jobs:
   my-job:
     ...
+    steps:
+    ...
+    - uses: xarray-contrib/minimum-dependency-versions@version
+      with:
+        environment-paths: path/to/env.yaml
+```
+
+To analyze multiple environments at the same time, pass a multi-line string:
+
+```yaml
+jobs:
+  my-job:
+    ...
+    steps:
+    ...
 
     - uses: xarray-contrib/minimum-dependency-versions@version
       with:
-        ...
+        environment-paths: |
+          path/to/env1.yaml
+          path/to/env2.yaml
+          path/to/env3.yaml
 ```
diff --git a/action.yaml b/action.yaml
index f9f852a..4690209 100644
--- a/action.yaml
+++ b/action.yaml
@@ -6,7 +6,7 @@ inputs:
     description: >-
       The paths to the environment files
     required: True
-    type: string
+    type: list
 outputs: {}
 
 runs:
@@ -22,5 +22,6 @@ runs:
       env:
         COLUMNS: 120
         FORCE_COLOR: 3
+        INPUT: ${{ inputs.environment-paths }}
       run: |
-        python minimum_versions.py ${{ join(fromJSON(inputs.environment-paths), ' ') }}
+        python minimum_versions.py $(echo $INPUT)