fix(ai): fail at setup when an AI integration's client lacks capture_ai

Author: eli-r-ph

.sampo/changesets/ai-integrations-require-capture-ai.md

@@ -0,0 +1,5 @@
+---
+pypi/posthog: major
+---
+
+The AI integrations no longer fall back to `capture` for a client object without `capture_ai`. Creating an OpenAI, Anthropic or Gemini wrapper, the LangChain `CallbackHandler`, or the OpenAI Agents or Claude Agent SDK processor with such a client now raises `TypeError`. The error shows up when you set the integration up, and not after a provider call. A `Client` or `AsyncPosthog` instance, and the default global client, work as before.

docs/migration-7.x-to-8.0.md

@@ -176,7 +176,7 @@ These changes follow from this order:
 
 - `capture_ai` and every built-in AI integration send to `/i/v1/ai/events`. The AI endpoint accepts events up to 8 MiB.
 - `enable_full_ai_capture` now controls only content: string truncation and media redaction. It no longer chooses the endpoint. `_use_ai_lane` and `_enable_multimodal_capture` still work as aliases.
-- The AI integrations call your client's `capture_ai`. A client object without `capture_ai` gets `capture` calls instead. A custom client must accept the `options` keyword argument.
+- The AI integrations call your client's `capture_ai`, and never `capture`. A custom client object must implement `capture_ai` and accept its `options` keyword argument. If the client has no `capture_ai`, the wrapper, callback handler or tracing processor raises `TypeError` when you create it. Before, such a client got `capture` calls.
 - Tests that pass a `Mock` client to an AI integration must assert on `mock.capture_ai`, not `mock.capture`.
 - When an AI integration or MCP falls back to a trace, run or session ID, it turns person processing off with a per-event option. This is the only option the integrations pass. It wins over `super_options`, context options and a `$process_person_profile: true` property. `before_send` can still change it.
 - The AI integrations have no `options` argument. To set options on their events, use `set_context_option`, `super_options`, or a legacy property such as `$cookieless_mode` in `posthog_properties`.

posthog/ai/anthropic/anthropic.py

@@ -17,6 +17,7 @@
     ToolInProgress as ToolInProgress,
 )
 from ..utils import (
+    _resolve_ai_client,
     call_llm_and_track_usage as call_llm_and_track_usage,
     merge_usage_stats as merge_usage_stats,
 )
@@ -29,7 +30,6 @@
     handle_anthropic_tool_delta as handle_anthropic_tool_delta,
 )
 from posthog.client import Client as PostHogClient
-from posthog import setup
 
 
 class Anthropic(anthropic.Anthropic):
@@ -46,7 +46,7 @@ def __init__(self, posthog_client: Optional[PostHogClient] = None, **kwargs):
             **kwargs: Additional arguments passed to the Anthropic client
         """
         super().__init__(**kwargs)
-        self._ph_client = posthog_client or setup()
+        self._ph_client = _resolve_ai_client(posthog_client)
         self.messages = WrappedMessages(self)
 
 

posthog/ai/anthropic/anthropic_async.py

@@ -10,14 +10,14 @@
 import uuid
 from typing import Any, Dict, List, Optional
 
-from posthog import setup
 from ..stream import AsyncStreamWrapper as AsyncStreamWrapper
 from ..types import (
     StreamingContentBlock as StreamingContentBlock,
     TokenUsage as TokenUsage,
     ToolInProgress as ToolInProgress,
 )
 from ..utils import (
+    _resolve_ai_client,
     call_llm_and_track_usage_async as call_llm_and_track_usage_async,
     merge_usage_stats as merge_usage_stats,
 )
@@ -46,7 +46,7 @@ def __init__(self, posthog_client: Optional[PostHogClient] = None, **kwargs):
             **kwargs: Additional arguments passed to the Anthropic client
         """
         super().__init__(**kwargs)
-        self._ph_client = posthog_client or setup()
+        self._ph_client = _resolve_ai_client(posthog_client)
         self.messages = AsyncWrappedMessages(self)
 
 

posthog/ai/anthropic/anthropic_providers.py

@@ -9,8 +9,8 @@
 
 from posthog.ai.anthropic.anthropic import WrappedMessages
 from posthog.ai.anthropic.anthropic_async import AsyncWrappedMessages
+from posthog.ai.utils import _resolve_ai_client
 from posthog.client import Client as PostHogClient
-from posthog import setup
 
 
 class AnthropicBedrock(anthropic.AnthropicBedrock):
@@ -28,7 +28,7 @@ def __init__(self, posthog_client: Optional[PostHogClient] = None, **kwargs):
             **kwargs: Arguments passed to ``anthropic.AnthropicBedrock``.
         """
         super().__init__(**kwargs)
-        self._ph_client = posthog_client or setup()
+        self._ph_client = _resolve_ai_client(posthog_client)
         self.messages = WrappedMessages(self)
 
 
@@ -47,7 +47,7 @@ def __init__(self, posthog_client: Optional[PostHogClient] = None, **kwargs):
             **kwargs: Arguments passed to ``anthropic.AsyncAnthropicBedrock``.
         """
         super().__init__(**kwargs)
-        self._ph_client = posthog_client or setup()
+        self._ph_client = _resolve_ai_client(posthog_client)
         self.messages = AsyncWrappedMessages(self)
 
 
@@ -66,7 +66,7 @@ def __init__(self, posthog_client: Optional[PostHogClient] = None, **kwargs):
             **kwargs: Arguments passed to ``anthropic.AnthropicVertex``.
         """
         super().__init__(**kwargs)
-        self._ph_client = posthog_client or setup()
+        self._ph_client = _resolve_ai_client(posthog_client)
         self.messages = WrappedMessages(self)
 
 
@@ -85,5 +85,5 @@ def __init__(self, posthog_client: Optional[PostHogClient] = None, **kwargs):
             **kwargs: Arguments passed to ``anthropic.AsyncAnthropicVertex``.
         """
         super().__init__(**kwargs)
-        self._ph_client = posthog_client or setup()
+        self._ph_client = _resolve_ai_client(posthog_client)
         self.messages = AsyncWrappedMessages(self)

posthog/ai/claude_agent_sdk/processor.py

@@ -24,14 +24,14 @@
         "Please install the Claude Agent SDK to use this feature: 'pip install claude-agent-sdk'"
     )
 
-from posthog import setup
 from posthog.ai.claude_agent_sdk.formatting import (
     format_assistant_blocks,
     format_tool_result_content,
 )
 from posthog.ai.media import ensure_serializable as _ensure_serializable
 from posthog.ai.utils import (
     _capture_processor_event,
+    _resolve_ai_client,
     finalize_ai_content,
     with_privacy_mode as _with_privacy_mode,
 )
@@ -167,7 +167,7 @@ def __init__(
             groups: Optional PostHog groups to associate with emitted events.
             properties: Additional properties included on emitted AI events.
         """
-        self._client = client or setup()
+        self._client = _resolve_ai_client(client)
         self._distinct_id = distinct_id
         self._privacy_mode = privacy_mode
         self._groups = groups or {}

posthog/ai/gemini/_shared.py

@@ -9,11 +9,11 @@
         "Please install the Google Gemini SDK to use this feature: 'pip install google-genai'"
     )
 
-from ... import setup
 from ...client import Client as PostHogClient
 from ..types import StreamingEventData, TokenUsage
 from ..utils import (
     _capture_ai_event,
+    _resolve_ai_client,
     capture_streaming_event,
     finalize_ai_content,
     merge_system_prompt,
@@ -27,15 +27,6 @@
 _GEMINI_BASE_URL = "https://generativelanguage.googleapis.com"
 
 
-def _resolve_posthog_client(
-    posthog_client: Optional[PostHogClient],
-) -> PostHogClient:
-    client = posthog_client or setup()
-    if client is None:
-        raise ValueError("posthog_client is required for PostHog tracking")
-    return client
-
-
 def _build_gemini_client_args(
     *,
     api_key: Optional[str],
@@ -138,7 +129,7 @@ def _initialize_policy(
         posthog_groups: Optional[Dict[str, Any]],
         provider_client: Optional[Any] = None,
     ) -> None:
-        self._ph_client = _resolve_posthog_client(posthog_client)
+        self._ph_client = _resolve_ai_client(posthog_client)
         self._default_distinct_id = posthog_distinct_id
         self._default_properties = posthog_properties or {}
         self._default_privacy_mode = posthog_privacy_mode

posthog/ai/gemini/gemini.py

@@ -6,6 +6,7 @@
 from ..types import StreamingEventData as StreamingEventData
 from ..types import TokenUsage
 from ..utils import (
+    _resolve_ai_client,
     call_llm_and_track_usage,
     capture_streaming_event as capture_streaming_event,
     finalize_ai_content as finalize_ai_content,
@@ -17,7 +18,6 @@
     _GeminiAioNamespace,
     _GeminiModelsPolicy,
     _build_gemini_client,
-    _resolve_posthog_client,
 )
 from .gemini_async import AsyncModels
 from .gemini_converter import (
@@ -92,7 +92,7 @@ def __init__(
             **kwargs: Additional arguments (for future compatibility)
         """
 
-        self._ph_client = _resolve_posthog_client(posthog_client)
+        self._ph_client = _resolve_ai_client(posthog_client)
 
         # Built once here and shared by every surface, so a client that uses both
         # `models` and `aio.models` still opens a single provider client.

posthog/ai/gemini/gemini_async.py

@@ -7,6 +7,7 @@
 from ..types import StreamingEventData as StreamingEventData
 from ..types import TokenUsage
 from ..utils import (
+    _resolve_ai_client,
     call_llm_and_track_usage_async,
     capture_streaming_event as capture_streaming_event,
     finalize_ai_content as finalize_ai_content,
@@ -18,7 +19,6 @@
     _GeminiAioNamespace,
     _GeminiModelsPolicy,
     _build_gemini_client,
-    _resolve_posthog_client,
 )
 from .gemini_converter import (
     extract_gemini_content_from_chunk,
@@ -87,7 +87,7 @@ def __init__(
             **kwargs: Additional arguments (for future compatibility)
         """
 
-        self._ph_client = _resolve_posthog_client(posthog_client)
+        self._ph_client = _resolve_ai_client(posthog_client)
 
         # Built once here and shared by every surface, so `models`, `aio.models`
         # and `files` all go through a single provider client.

posthog/ai/langchain/callbacks.py

@@ -41,11 +41,11 @@
 from langchain_core.outputs import ChatGeneration, LLMResult
 from pydantic import BaseModel
 
-from posthog import setup
 from posthog.ai.gateway import warn_if_posthog_ai_gateway
 from posthog.ai.utils import (
     _capture_ai_event,
     _extract_cache_creation_ttl_breakdown,
+    _resolve_ai_client,
     finalize_ai_content,
     get_model_params,
     _responses_stop_reason,
@@ -145,7 +145,7 @@ def __init__(
             privacy_mode: Whether to redact the input and output of the trace.
             groups: Optional additional PostHog groups to use for the trace.
         """
-        self._ph_client = client or setup()
+        self._ph_client = _resolve_ai_client(client)
         self._distinct_id = distinct_id
         self._trace_id = trace_id
         self._properties = properties or {}