error_classifier.py: Message-only auth errors ("invalid api key", "unauthorized",
etc.) were classified as retryable=True (line 707), inconsistent with the HTTP 401
path (line 432) which correctly uses retryable=False + should_fallback=True. The
mismatch causes 3 wasted retries with the same broken credential before fallback,
while 401 errors immediately attempt fallback. Align the message-based path to
match: retryable=False, should_fallback=True.
web_tools.py: The _PREFIX_RE secret-detection check in web_extract_tool() runs
against the raw URL string (line 1196). URL-encoded secrets like %73k-1234... (
sk-1234...) bypass the filter because the regex expects literal ASCII. Add
urllib.parse.unquote() before the check so percent-encoded variants are also caught.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
Auth errors matched by message pattern were incorrectly marked retryable=True, causing futile retry loops. Aligns with _classify_by_status() which already sets retryable=False for 401/403. Fixes#7026. Contributed by @kuishou68.
_classify_by_message had no handling for _USAGE_LIMIT_PATTERNS, so
messages like 'usage limit exceeded, try again in 5 minutes' arriving
without an HTTP status code fell through to FailoverReason.unknown
instead of rate_limit.
Apply the same billing/rate-limit disambiguation that _classify_402
already uses: USAGE_LIMIT_PATTERNS + transient signal → rate_limit,
USAGE_LIMIT_PATTERNS alone → billing.
Add 4 tests covering the no-status-code usage-limit path.
The error classifier's generic-400 heuristic only extracted err_body_msg from
the nested body structure (body['error']['message']), missing the flat body
format used by OpenAI's Responses API (body['message']). This caused
descriptive 400 errors like 'Invalid input[index].name: string does not match
pattern' to appear generic when the session was large, misclassifying them as
context overflow and triggering an infinite compression loop.
Added flat-body fallback in _classify_400() consistent with the parent
classify_api_error() function's existing handling at line 297-298.
