fix(redaction): gate ambiguous assignment values

agent/redact.py

@@ -270,6 +270,16 @@ _KEY_KEYWORD_RE = re.compile(
     re.IGNORECASE,
 )
 
+# Key names that are credential-specific even when their values are short or
+# human-readable. Bare ``token`` / ``key`` are intentionally absent: those
+# words also describe model limits, tensor names, cache keys, and other public
+# technical values. Their assignments are gated on value shape below.
+_STRONG_KEY_KEYWORD_RE = re.compile(
+    r"(?:api|auth|access|refresh|session|id|bearer)[ _.\\-]?(?:key|token)"
+    r"|key[ _.\\-]?material|secret|passwd|password|pass|pw|credential|auth|bearer",
+    re.IGNORECASE,
+)
+
 
 def _is_word_start(s: str, i: int) -> bool:
     """True if position ``i`` in ``s`` begins a word (not mid-word)."""
@@ -326,6 +336,42 @@ def _key_has_secret_keyword(key: str) -> bool:
             return True
     return False
 
+
+def _key_has_strong_secret_keyword(key: str) -> bool:
+    """Return whether ``key`` names an unambiguously credential-bearing field."""
+    for match in _STRONG_KEY_KEYWORD_RE.finditer(key):
+        if _is_word_start(key, match.start()) and _is_word_end(key, match.end()):
+            return True
+    return False
+
+
+def _looks_like_opaque_credential(value: str) -> bool:
+    """Return whether an ambiguous token/key value has credential-like shape.
+
+    Known vendor prefixes and JWTs have dedicated redactors. This catches the
+    remaining opaque family without treating short technical scalars such as
+    ``CPU``, ``local``, or training captions as secrets merely because their
+    key contains ``token`` or ``key``.
+    """
+    if value == "***" or value.startswith("«redacted:"):
+        return True
+    if len(value) >= 16 and re.fullmatch(r"[A-Fa-f0-9]+", value):
+        return True
+    if len(value) >= 20 and re.fullmatch(r"[A-Za-z0-9_./+=-]+", value):
+        return True
+    if len(value) < 12:
+        return False
+    classes = sum(
+        bool(re.search(pattern, value))
+        for pattern in (r"[a-z]", r"[A-Z]", r"[0-9]")
+    )
+    return classes >= 2
+
+
+def _assignment_value_requires_redaction(key: str, value: str) -> bool:
+    """Apply value-aware gating to key-name-only assignment matches."""
+    return _key_has_strong_secret_keyword(key) or _looks_like_opaque_credential(value)
+
 # JSON field patterns: "apiKey": "value", "token": "value", etc.
 _JSON_KEY_NAMES = r"(?:api_?[Kk]ey|token|secret|password|access_token|refresh_token|auth_token|bearer|secret_value|raw_secret|secret_input|key_material)"
 _JSON_FIELD_RE = re.compile(
@@ -870,6 +916,8 @@ def redact_sensitive_text(
                 # embedded matching inside the helper.
                 if not _key_has_secret_keyword(name):
                     return m.group(0)
+                if not _assignment_value_requires_redaction(name, value):
+                    return m.group(0)
                 return f"{name}={quote}{_mask_token(value)}{quote}"
             text = _ENV_ASSIGN_RE.sub(_redact_env, text)
             # Lowercase env names (``openai_key=…``). Skip URLs — the query
@@ -905,6 +953,8 @@ def redact_sensitive_text(
                 # not a leaked secret value.
                 if _ENV_LOOKUP_VALUE_RE.match(value):
                     return m.group(0)
+                if not _assignment_value_requires_redaction(key, value):
+                    return m.group(0)
                 return f'{key}: "{_mask_token(value)}"'
             text = _JSON_FIELD_RE.sub(_redact_json, text)
 
@@ -924,6 +974,8 @@ def redact_sensitive_text(
                 # document text, not credentials (nearai/ironclaw#6129).
                 if not _key_has_secret_keyword(key):
                     return m.group(0)
+                if not _assignment_value_requires_redaction(key, value):
+                    return m.group(0)
                 return f"{key}{sep}{_mask_token(value)}"
             text = _YAML_ASSIGN_RE.sub(_redact_yaml, text)
 

tests/agent/test_redact.py

@@ -100,6 +100,37 @@ class TestEnvAssignments:
         result = redact_sensitive_text(text)
         assert result == text
 
+    @pytest.mark.parametrize(
+        "text",
+        [
+            'IDENTITY_TOKEN="bailu"',
+            "--override-tensor per_layer_token_embd.weight=CPU",
+            'runtime.token="local"',
+            '{"token": "CPU"}',
+            "token: CPU",
+        ],
+    )
+    def test_ambiguous_key_preserves_obviously_noncredential_value(self, text):
+        assert redact_sensitive_text(text, force=True) == text
+
+    @pytest.mark.parametrize(
+        "text, cleartext",
+        [
+            ("PASSWORD=hunter2", "hunter2"),
+            ("SECRET_TOKEN=bailu", "bailu"),
+            ("id_token=local", "local"),
+            ("CUSTOM_TOKEN=opaqueValue123456789", "opaqueValue123456789"),
+            ('{"token": "opaqueValue123456789"}', "opaqueValue123456789"),
+            ('{"key_material": "CPU"}', "CPU"),
+            ('{"bearer": "local"}', "local"),
+            ("TOKEN=" + "sk-" + "a" * 30, "a" * 20),
+        ],
+    )
+    def test_strong_key_or_credential_shaped_value_still_redacts(
+        self, text, cleartext
+    ):
+        assert cleartext not in redact_sensitive_text(text, force=True)
+