René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"LiteLLMIntegration stores a non-JSON-serializable Span in request metadata, breaking outbound LLM requests","articleBody":"### How do you use Sentry?\n\nSentry SaaS (sentry.io)\n\n### Version\n\n`sentry-sdk` 2.52.0 (also present on current `master`); `litellm` 1.81.9; Python 3.13\n\n### Steps to Reproduce\n\nWith the LiteLLM integration enabled, any call that passes caller `metadata` crashes during request serialization:\n\n```python\nimport asyncio, litellm, sentry_sdk\nfrom sentry_sdk.integrations.litellm import LiteLLMIntegration\n\nsentry_sdk.init(\n    dsn=\"\u003cyour-dsn\u003e\", traces_sample_rate=1.0,\n    send_default_pii=True, integrations=[LiteLLMIntegration()],\n)\n\nasync def main():\n    await litellm.anthropic.messages.acreate(\n        model=\"anthropic/claude-3-5-sonnet-latest\",\n        messages=[{\"role\": \"user\", \"content\": \"hi\"}],\n        max_tokens=16, stream=True, api_key=\"sk-ant-...\",\n        metadata={\"user_id\": \"my-org\"},   # Anthropic abuse-isolation id\n    )\n\nasyncio.run(main())\n```\n\n**Root cause:** `_input_callback` stores the live span via `_get_metadata_dict(kwargs)[\"_sentry_span\"] = span` (`sentry_sdk/integrations/litellm.py`). litellm's Anthropic `/v1/messages` passthrough forwards `metadata` into the request body, so the live `Span` lands at `request_body['metadata']['_sentry_span']` and `json.dumps(request_body)` fails — before the request is sent.\n\n### Expected Result\n\nEnabling the integration must not make outbound provider requests unserializable. The integration's bookkeeping span should be stashed off-band (e.g. a `WeakKeyDictionary` keyed on the logging object) rather than written into the caller's request `metadata` dict, which several providers (Anthropic here) forward into the wire payload.\n\n### Actual Result\n\n```\nTypeError: Object of type Span is not JSON serializable\n```\n\n(a `Transaction` when there is no active parent span). Separately, with `send_default_pii=True` + `include_prompts=True` (the default), that span's `gen_ai.request.messages` holds the **verbatim prompt** — so any sink that serializes this span object can leak prompt content.\n\n---\n\nRelated (defense-in-depth, downstream): litellm forwards/serializes this injected metadata into the provider body. Companion issue filed at BerriAI/litellm — see comment below. litellm has stripped such span objects in other logging paths: BerriAI/litellm#15728, BerriAI/litellm#12354.\n","author":{"url":"https://github.com/jgreer013","@type":"Person","name":"jgreer013"},"datePublished":"2026-06-17T16:41:36.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/6596/sentry-python/issues/6596"}