fix: sanitize unsupported image MIME types (e.g. GIF) in context cleaner

astrbot/core/agent/context/compressor.py

@@ -268,6 +268,7 @@ async def __call__(self, messages: list[Message]) -> list[Message]:
         sanitized_summary_contexts, sanitize_stats = sanitize_contexts_by_modalities(
             summary_contexts,
             self.provider.provider_config.get("modalities", None),
+            self.provider.provider_config.get("supported_image_mimes", None),
         )
         log_context_sanitize_stats(sanitize_stats)
 

astrbot/core/agent/runners/tool_loop_agent_runner.py

@@ -661,6 +661,7 @@ def _sanitize_contexts_for_provider(
         sanitized_contexts, stats = sanitize_contexts_by_modalities(
             contexts,
             self.provider.provider_config.get("modalities", None),
+            self.provider.provider_config.get("supported_image_mimes", None),
         )
         log_context_sanitize_stats(stats)
         return sanitized_contexts

astrbot/core/config/default.py

@@ -2207,6 +2207,23 @@
                         "render_type": "checkbox",
                         "hint": "模型支持的模态及能力。",
                     },
+                    "supported_image_mimes": {
+                        "description": "支持的图片 MIME 类型",
+                        "type": "list",
+                        "items": {"type": "string"},
+                        "options": [
+                            "image/jpeg",
+                            "image/png",
+                            "image/webp",
+                            "image/gif",
+                        ],
+                        "labels": ["JPEG", "PNG", "WebP", "GIF"],
+                        "render_type": "checkbox",
+                        "hint": (
+                            "模型支持的图片格式。不勾选时保留全部（仅过滤已知不安全格式如 GIF）。"
+                            "勾选后仅保留勾选的格式。"
+                        ),
+                    },
                     "custom_headers": {
                         "description": "自定义请求头",
                         "type": "dict",

astrbot/core/provider/modalities.py

@@ -4,6 +4,7 @@
 from collections.abc import Sequence
 from dataclasses import dataclass
 from typing import Any
+from urllib.parse import urlsplit
 
 from astrbot import logger
 from astrbot.core.agent.message import Message
@@ -34,10 +35,98 @@ def _message_to_dict(message: dict[str, Any] | Message) -> dict[str, Any] | None
     return None
 
 
+# Image MIME types that some OpenAI-compatible gateways reject even when the
+# model claims image support. Animated GIFs in particular are accepted by raw
+# Gemini (which wants image/heif/video/mp4 for animations) but rejected by
+# several Gemini-flavored OpenAI proxies with "mime type is not supported".
+# Keeping this list narrow avoids over-stripping providers that do accept GIF
+# (e.g. Anthropic Claude). See issue #9295.
+_UNSUPPORTED_IMAGE_MIMES = frozenset({"image/gif"})
+
+# Lazily-built extension → MIME mapping used only for http(s) URL fallback.
+_IMAGE_EXT_TO_MIME: dict[str, str] = {
+    ".gif": "image/gif",
+}
+
+
+def _extract_image_mime(part: dict[str, Any]) -> str | None:
+    """Best-effort extraction of an image MIME type from a multimodal part.
+
+    Handles the OpenAI-style ``{"image_url": {"url": ...}}`` and the Anthropic /
+    Gemini-style ``{"source": {"media_type": ...}}`` / ``{"mimeType": ...}``
+    layouts, as well as a bare ``{"url": ...}`` or ``{"image_url": "<url>"}``.
+
+    Returns:
+        The normalized MIME type (e.g. ``image/gif``) if it can be determined,
+        otherwise ``None``.
+    """
+    image_url = part.get("image_url")
+    if isinstance(image_url, dict):
+        url = image_url.get("url")
+    else:
+        url = image_url
+    if not isinstance(url, str):
+        url = part.get("url") if isinstance(part.get("url"), str) else None
+
+    if isinstance(url, str):
+        url = url.strip()
+        # data URLs look like "data:image/gif;base64,...."
+        if url.lower().startswith("data:"):
+            head = url[5:].split(",", 1)[0]
+            # head is e.g. "image/gif;base64"
+            mime = head.split(";", 1)[0].strip().lower()
+            if mime:
+                return mime
+        else:
+            # Fall back to the URL path extension for http(s) URLs. urlsplit
+            # robustly separates the path from query/fragment even when those
+            # delimiters appear percent-encoded inside the path itself.
+            path = urlsplit(url).path.lower()
+            for ext, mime in _IMAGE_EXT_TO_MIME.items():
+                if path.endswith(ext):
+                    return mime
+
+    source = part.get("source")
+    if isinstance(source, dict):
+        media_type = source.get("media_type")
+        if isinstance(media_type, str):
+            # Normalize by stripping parameters (e.g. "image/gif; charset=binary"
+            # -> "image/gif") so it matches _UNSUPPORTED_IMAGE_MIMES.
+            return media_type.split(";", 1)[0].strip().lower()
+
+    mime_type = part.get("mimeType") or part.get("mime_type")
+    if isinstance(mime_type, str):
+        # Strip parameters (e.g. "image/gif;codec=xyz" -> "image/gif") to align
+        # with the data-URL and source.media_type handling above.
+        return mime_type.split(";", 1)[0].strip().lower()
+
+    return None
+
+
+def _is_unsupported_image_mime(mime: str | None) -> bool:
+    """Return True when the MIME is known to be rejected by some providers."""
+    return bool(mime) and mime in _UNSUPPORTED_IMAGE_MIMES
+
+
 def sanitize_contexts_by_modalities(
     contexts: Sequence[dict[str, Any] | Message],
     modalities: list[str] | None,
+    supported_image_mimes: list[str] | None = None,
 ) -> tuple[list[dict[str, Any]], ContextSanitizeStats]:
+    """Sanitize message contexts based on provider capabilities.
+
+    Args:
+        contexts: The message contexts to sanitize.
+        modalities: List of modalities the provider supports (e.g. ["text", "image"]).
+        supported_image_mimes: Whitelist of image MIME types the provider accepts.
+            When None or empty, a fallback blocklist (_UNSUPPORTED_IMAGE_MIMES) is used
+            to filter known-problematic formats (e.g. image/gif for some Gemini gateways).
+            When provided, images with MIME types not in this list are replaced with
+            "[Image]" placeholders.
+
+    Returns:
+        Tuple of (sanitized contexts, statistics).
+    """
     if not contexts:
         return [], ContextSanitizeStats()
     if not modalities or not isinstance(modalities, list):
@@ -51,7 +140,13 @@ def sanitize_contexts_by_modalities(
     supports_image = "image" in modalities
     supports_audio = "audio" in modalities
     supports_tool_use = "tool_use" in modalities
-    if supports_image and supports_audio and supports_tool_use:
+    # Determine whether we need a MIME-filtering pass. When a whitelist is
+    # provided, we always filter; otherwise we fall back to the hardcoded
+    # blocklist for known-problematic MIME types (e.g. image/gif).
+    needs_mime_pass = supports_image and (
+        bool(supported_image_mimes) or bool(_UNSUPPORTED_IMAGE_MIMES)
+    )
+    if supports_image and supports_audio and supports_tool_use and not needs_mime_pass:
         copied_contexts = []
         for msg in contexts:
             copied_msg = _message_to_dict(msg)
@@ -83,15 +178,36 @@ def sanitize_contexts_by_modalities(
                 msg.pop("tool_calls", None)
                 msg.pop("tool_call_id", None)
 
-        if not supports_image or not supports_audio:
+        if not supports_image or not supports_audio or needs_mime_pass:
             content = msg.get("content")
             if isinstance(content, list):
                 filtered_parts: list[Any] = []
                 removed_any_multimodal = False
                 for part in content:
                     if isinstance(part, dict):
                         part_type = str(part.get("type", "")).lower()
-                        if not supports_image and part_type in {"image_url", "image"}:
+                        # Determine whether this image part should be dropped.
+                        should_drop_image = False
+                        if part_type in {"image_url", "image"}:
+                            if not supports_image:
+                                # Provider declares no image support at all.
+                                should_drop_image = True
+                            else:
+                                # Provider supports image, but may have MIME restrictions.
+                                mime = _extract_image_mime(part)
+                                if supported_image_mimes:
+                                    # Whitelist mode: drop if MIME not in the list.
+                                    if mime not in supported_image_mimes:
+                                        should_drop_image = True
+                                else:
+                                    # Fallback blocklist mode: drop if MIME is known
+                                    # to be rejected by some gateways (e.g. image/gif).
+                                    if _is_unsupported_image_mime(mime):
+                                        should_drop_image = True
+                        if should_drop_image:
+                            # Replacing the block with a placeholder prevents unsupported
+                            # bytes from being persisted into the session history and
+                            # poisoning all subsequent requests. See issue #9295.
                             removed_any_multimodal = True
                             stats.fixed_image_blocks += 1
                             filtered_parts.append({"type": "text", "text": "[Image]"})

dashboard/src/i18n/locales/en-US/features/config-metadata.json

@@ -1404,6 +1404,16 @@
           "Tool use"
         ]
       },
+      "supported_image_mimes": {
+        "description": "Supported image MIME types",
+        "hint": "Image formats the model accepts. When unchecked, all formats are kept (only known-unsafe formats like GIF are filtered on some gateways). When checked, only selected formats are preserved.",
+        "labels": [
+          "JPEG",
+          "PNG",
+          "WebP",
+          "GIF"
+        ]
+      },
       "custom_headers": {
         "description": "Custom request headers",
         "hint": "Key/value pairs added here are merged into the OpenAI SDK default_headers for custom HTTP headers. Values must be strings."

dashboard/src/i18n/locales/zh-CN/features/config-metadata.json

@@ -1427,6 +1427,16 @@
           "工具使用"
         ]
       },
+      "supported_image_mimes": {
+        "description": "支持的图片 MIME 类型",
+        "hint": "模型支持的图片格式。不勾选时保留全部（仅过滤已知不安全格式如 GIF）。勾选后仅保留勾选的格式。",
+        "labels": [
+          "JPEG",
+          "PNG",
+          "WebP",
+          "GIF"
+        ]
+      },
       "custom_headers": {
         "description": "自定义请求头",
         "hint": "此处添加的键值对将被合并到 OpenAI SDK 的 default_headers 中，用于自定义 HTTP 请求头。值必须为字符串。"