diff --git a/agent/redact.py b/agent/redact.py
index 1beb10450fdf..1b08591d9daa 100644
--- a/agent/redact.py
+++ b/agent/redact.py
@@ -344,6 +344,15 @@ def redact_sensitive_text(text: str, *, force: bool = False, code_file: bool = F
     if _has_known_prefix_substring(text):
         text = _PREFIX_RE.sub(lambda m: _mask_token(m.group(1)), text)
 
+    # ENV assignments: OPENAI_API_KEY=sk-abc...
+    def _redact_env(m):
+        name, quote, value = m.group(1), m.group(2), m.group(3)
+        # Skip programmatic env lookups — these reference variable *names*,
+        # not actual secret values (fixes #2852).
+        if re.match(r"os\.(?:getenv|environ)", value):
+            return m.group(0)
+        return f"{name}={quote}{_mask_token(value)}{quote}"
+    text = _ENV_ASSIGN_RE.sub(_redact_env, text)
     # ENV assignments: OPENAI_API_KEY=***  (skip for code files — false positives)
     if not code_file:
         if "=" in text:
diff --git a/tests/agent/test_redact.py b/tests/agent/test_redact.py
index 928eb1ff357e..b05279d013cb 100644
--- a/tests/agent/test_redact.py
+++ b/tests/agent/test_redact.py
@@ -115,6 +115,51 @@ def test_export_whitespace_preserved(self):
         assert "mypassword" not in result
 
 
+class TestEnvLookupPreserved:
+    """Programmatic env var lookups must not be corrupted (issue #2852)."""
+
+    def test_os_getenv_single_quote(self):
+        text = "ha_token=os.getenv('HOMEASSISTANT_TOKEN')"
+        result = redact_sensitive_text(text)
+        assert result == text
+
+    def test_os_getenv_double_quote(self):
+        text = 'api_token=os.getenv("MY_API_TOKEN")'
+        result = redact_sensitive_text(text)
+        assert result == text
+
+    def test_os_environ_get(self):
+        text = "self.token=os.environ.get('HOMEASSISTANT_TOKEN')"
+        result = redact_sensitive_text(text)
+        assert result == text
+
+    def test_os_environ_bracket(self):
+        text = "secret=os.environ['MY_SECRET']"
+        result = redact_sensitive_text(text)
+        assert result == text
+
+    def test_spaced_assignment(self):
+        text = "ha_token = os.getenv('HOMEASSISTANT_TOKEN')"
+        result = redact_sensitive_text(text)
+        assert result == text
+
+    def test_real_env_value_still_redacted(self):
+        text = "HOMEASSISTANT_TOKEN=eyJhbGciOiJIUzI1NiJ9.abc123.xyz"
+        result = redact_sensitive_text(text)
+        assert "eyJhbGciOiJIUzI1NiJ9" not in result
+
+    def test_multiline_skill_file(self):
+        text = """def _get_credentials():
+    ha_url = os.getenv('HOMEASSISTANT_URL')
+    ha_token=os.getenv('HOMEASSISTANT_TOKEN')
+    if not ha_url or not ha_token:
+        raise ValueError('Missing credentials')
+    return ha_url, ha_token"""
+        result = redact_sensitive_text(text)
+        assert "os.getenv('HOMEASSISTANT_TOKEN')" in result
+        assert "os.getenv('HOMEASSISTANT_URL')" in result
+
+
 class TestJsonFields:
     def test_json_api_key(self):
         text = '{"apiKey": "sk-proj-abc123def456ghi789jkl012"}'