diff --git a/package/hemar/parser/hemar.sh b/package/hemar/parser/hemar.sh
index 43df862..0463015 100644
--- a/package/hemar/parser/hemar.sh
+++ b/package/hemar/parser/hemar.sh
@@ -108,7 +108,17 @@
 #
 # Interpolation = {
 #   "type": "interpolation",
-#   "path": string     # path to variable in data model
+#   "path": [PathSegment, ...]  # structured path to variable in data model
+# }
+#
+# PathSegment = {
+#   "type": "root"              # root path: "."
+# } | {
+#   "type": "key",
+#   "key": string              # key name (can contain spaces if quoted)
+# } | {
+#   "type": "index",
+#   "index": number            # array index (can be negative)
 # }
 #
 # Element types (planned for MVP):
diff --git a/test/package/hemar/test/parser-interpolation.sh b/test/package/hemar/test/parser-interpolation.sh
index 9e78b56..0ceca09 100644
--- a/test/package/hemar/test/parser-interpolation.sh
+++ b/test/package/hemar/test/parser-interpolation.sh
@@ -5,37 +5,37 @@
 
 log notice "test case: ${WHITE}simple interpolation"
 answer="$(printf '%s' '{[hello]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"hello"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"hello"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}interpolation with text before and after"
 answer="$(printf '%s' 'foo {[bar]} baz' | hemar -c)"
-expected='[{"type":"text","value":"foo "},{"type":"interpolation","path":"bar"},{"type":"text","value":" baz"}]'
+expected='[{"type":"text","value":"foo "},{"type":"interpolation","path":[{"type":"key","key":"bar"}]},{"type":"text","value":" baz"}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}root path"
 answer="$(printf '%s' '{[.]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"."}]'
+expected='[{"type":"interpolation","path":[{"type":"root"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}simple path"
 answer="$(printf '%s' '{[key]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"key"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"key"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}dot-separated path"
 answer="$(printf '%s' '{[key.subkey]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"key.subkey"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"key"},{"type":"key","key":"subkey"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}long path"
 answer="$(printf '%s' '{[key.subkey.subsubkey]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"key.subkey.subsubkey"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"key"},{"type":"key","key":"subkey"},{"type":"key","key":"subsubkey"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}multiple interpolations"
 answer="$(printf '%s' '{[a]} {[b]} {[c]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"a"},{"type":"text","value":" "},{"type":"interpolation","path":"b"},{"type":"text","value":" "},{"type":"interpolation","path":"c"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"a"}]},{"type":"text","value":" "},{"type":"interpolation","path":[{"type":"key","key":"b"}]},{"type":"text","value":" "},{"type":"interpolation","path":[{"type":"key","key":"c"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test passed"
diff --git a/test/package/hemar/test/parser-paths.sh b/test/package/hemar/test/parser-paths.sh
index 566d2f9..177173c 100644
--- a/test/package/hemar/test/parser-paths.sh
+++ b/test/package/hemar/test/parser-paths.sh
@@ -5,42 +5,42 @@
 
 log notice "test case: ${WHITE}quoted string in path"
 answer="$(printf '%s' '{["key with spaces"]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"key with spaces"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"key with spaces"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}quoted dot in path"
 answer="$(printf '%s' '{[".key"]}' | hemar -c)"
-expected='[{"type":"interpolation","path":".key"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":".key"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}quoted vs unquoted dot"
 answer="$(printf '%s' '{["."]} {[.]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"."},{"type":"text","value":" "},{"type":"interpolation","path":"."}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"."}]},{"type":"text","value":" "},{"type":"interpolation","path":[{"type":"root"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}path with index"
 answer="$(printf '%s' '{[key[0]]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"key[0]"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"key"},{"type":"index","index":0}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}path with multiple indices"
 answer="$(printf '%s' '{[[0][1][2]]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"[0][1][2]"}]'
+expected='[{"type":"interpolation","path":[{"type":"index","index":0},{"type":"index","index":1},{"type":"index","index":2}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}path with negative index"
 answer="$(printf '%s' '{[key[-1]]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"key[-1]"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"key"},{"type":"index","index":-1}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}complex path with mixed segments"
 answer="$(printf '%s' '{["key".subkey[0]."subsubkey"]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"key.subkey[0].subsubkey"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"key"},{"type":"key","key":"subkey"},{"type":"index","index":0},{"type":"key","key":"subsubkey"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test case: ${WHITE}quoted string with escaped quote"
 answer="$(printf '%s' '{["key""with""quotes"]}' | hemar -c)"
-expected='[{"type":"interpolation","path":"key\"with\"quotes"}]'
+expected='[{"type":"interpolation","path":[{"type":"key","key":"key\"with\"quotes"}]}]'
 json_diff "$answer" "$expected"
 
 log notice "test passed"