lmproto: add DeepSeek Anthropic client

src/plyngent/agent/types.py

@@ -3,10 +3,19 @@
 from __future__ import annotations
 
 from plyngent.lmproto.anthropic.client import AnthropicClient
-from plyngent.lmproto.deepseek import DeepseekOpenAIClient, DeepseekResponsesClient
+from plyngent.lmproto.deepseek import (
+    DeepseekAnthropicClient,
+    DeepseekOpenAIClient,
+    DeepseekResponsesClient,
+)
 from plyngent.lmproto.openai.client import OpenAIClient
 from plyngent.lmproto.openai_compatible.client import OpenAICompatibleClient
 
 type AnyLLMClient = (
-    OpenAICompatibleClient | DeepseekOpenAIClient | DeepseekResponsesClient | OpenAIClient | AnthropicClient
+    OpenAICompatibleClient
+    | DeepseekOpenAIClient
+    | DeepseekResponsesClient
+    | DeepseekAnthropicClient
+    | OpenAIClient
+    | AnthropicClient
 )

src/plyngent/lmproto/deepseek/__init__.py

@@ -1,3 +1,4 @@
+from .anthropic.client import DeepseekAnthropicClient as DeepseekAnthropicClient
 from .openai_compat.client import DeepseekOpenAIClient as DeepseekOpenAIClient
 from .openai_compat.model import AnyChatMessage as AnyChatMessage
 from .openai_compat.model import AssistantChatMessage as AssistantChatMessage

src/plyngent/lmproto/deepseek/anthropic/__init__.py

@@ -0,0 +1 @@
+from .client import DeepseekAnthropicClient as DeepseekAnthropicClient

src/plyngent/lmproto/deepseek/anthropic/client.py

@@ -0,0 +1,35 @@
+"""DeepSeek Anthropic Messages client (``POST /messages`` on the DeepSeek endpoint)."""
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, override
+
+from plyngent.lmproto.anthropic.client import AnthropicClient
+
+if TYPE_CHECKING:
+    from plyngent.lmproto.anthropic.config import AnthropicConfig
+
+
+class DeepseekAnthropicClient(AnthropicClient):
+    """Anthropic Messages client pointed at DeepSeek's Anthropic-compatible endpoint.
+
+    DeepSeek exposes the Anthropic API format at ``https://api.deepseek.com/anthropic``
+    (see https://api-docs.deepseek.com/guides/anthropic_api). ``x-api-key`` is fully
+    supported; ``anthropic-version`` / ``anthropic-beta`` headers are ignored by the
+    server but harmless. Model ids map server-side: ``claude-opus*`` → ``deepseek-v4-pro``,
+    ``claude-haiku*`` / ``claude-sonnet*`` → ``deepseek-v4-flash``, unknown names →
+    ``deepseek-v4-flash``; real DeepSeek ids pass through as-is.
+
+    ``GET /models`` is not documented on the ``/anthropic`` base, so ``models()``
+    returns an empty list and model selection stays config-driven.
+    """
+
+    kind: str = "messages"
+
+    def __init__(self, config: AnthropicConfig) -> None:
+        super().__init__(config)
+
+    @override
+    async def models(self) -> list[str]:
+        """No documented ``GET /models`` on DeepSeek's ``/anthropic`` base."""
+        return []