fix(agent): use /anthropic endpoint for MiniMax-CN auxiliary tasks

[alexzhu0]

Closes #17387.

Summary

auxiliary_client._to_openai_base_url() unconditionally rewrites /anthropic → /v1 so the OpenAI SDK can hit chat.completions. For most providers that's correct — MiniMax exposes both surfaces and the OpenAI-compatible one lives at /v1. But MiniMax-CN's /v1 endpoint does not support auxiliary tasks (title generation, context compression, summarization), so every aux request 404s.

MiniMax-CN only serves those endpoints via the /anthropic surface, and we already have an AnthropicAuxiliaryClient wrapper (_maybe_wrap_anthropic) ready to consume that shape.

Fix

Thread a provider= kwarg into _to_openai_base_url. When the provider is in _ANTHROPIC_COMPAT_PROVIDERS (currently {"minimax", "minimax-cn"}), skip the /anthropic → /v1 rewrite so _maybe_wrap_anthropic can detect and route through the Anthropic Messages API instead.

-def _to_openai_base_url(base_url: str) -> str:
+def _to_openai_base_url(base_url: str, *, provider: str = "") -> str:
     url = str(base_url or "").strip().rstrip("/")
+    if provider and provider in _ANTHROPIC_COMPAT_PROVIDERS:
+        return url  # preserve /anthropic — _maybe_wrap_anthropic will handle it
     if url.endswith("/anthropic"):
         rewritten = url[: -len("/anthropic")] + "/v1"
         …

All 6 call sites in agent/auxiliary_client.py updated to pass the provider they already have in local scope. Behavior unchanged for every non-MiniMax provider; the existing rewrite still fires when provider="", "openai", "custom", etc.

Tests

Added TestToOpenaiBaseUrl in tests/agent/test_auxiliary_client.py with 7 regression cases:

• default rewrite behavior (preserved)
• provider-gated preservation for minimax and minimax-cn
• empty-provider fallback (preserved)
• trailing-slash normalization
• unrelated provider (openai) still gets the rewrite

Local inline verification of the logic: 6/6 pass. (Full pytest run requires Python 3.10+; my local env is 3.9 so CI will cover the test suite.)

Verification path

With this PR, an aux request on MiniMax-CN ends up on /anthropic/messages via AnthropicAuxiliaryClient instead of /v1/chat/completions (404). Compression / title generation / summarization on minimax-cn should recover.

Files

• agent/auxiliary_client.py: +10 / -3 (function signature + 6 call sites)
• tests/agent/test_auxiliary_client.py: +87

[ar-nim]

Same issue happens with minimax global. Can you extend the fix to minimax global too?

[alexzhu0]

Thanks @ar-nim — just verified: the fix already covers both. _ANTHROPIC_COMPAT_PROVIDERS = frozenset({"minimax", "minimax-cn"}) includes the global slug.

minimax is the canonical provider id for MiniMax Global (see hermes_cli/auth.py:250-283, where "minimax" and "minimax-cn" are registered as separate ProviderConfig entries). So configuring with provider: minimax in your config.yaml already benefits from the /anthropic preservation in this PR.

If you're seeing the failure despite that — could you share the provider: value in your config.yaml and a sample log line? If it's a different slug (e.g. minimax-global, minimax-m2, mm), we can add a normalization alias. Otherwise I'd expect the fix to resolve the 404s as-is.

[teknium1]

Closing as duplicate — #17467 (merged as 4e296dc) fixes this more broadly. Your allowlist approach (_ANTHROPIC_COMPAT_PROVIDERS in _to_openai_base_url) is narrower: it only catches the two MiniMax providers in the set, while #17467's approach (split raw_base_url from rewritten base_url at the call sites) also fixes Kimi Coding, anthropic_messages custom proxies, and any future /anthropic-suffixed gateway via the shared _endpoint_speaks_anthropic_messages detector. Thanks for the diagnosis and the thorough test plan.