> AI agents: this is one page from PostHog's docs. Full index of Markdown docs for LLMs: https://posthog.com/llms.txt

# Capturing large AI events - Docs

Copy page

# Capturing large AI events - Docs

**Public beta**

Large event capture is in public beta, available in [posthog-python](/docs/libraries/python.md#ai-observability) 7.39+ and [posthog-node](/docs/libraries/node.md#ai-observability) 5.49+ (with `@posthog/ai` 8.8+). We'd love to [hear your feedback](https://app.posthog.com/ai-observability#panel=support%3Afeedback%3Allm-analytics%3Alow%3Atrue) as we roll it out.

AI events can get big – a single generation can carry megabytes of prompt context or base64-encoded media, more than regular event capture accepts. To handle this, PostHog sends AI events like `$ai_generation` and `$ai_embedding` through a dedicated ingestion path that accepts events up to **8MB**.

During the beta, this path is opt-in. How you opt in depends on how you capture AI events today.

## Using the SDK integrations

By default, our [SDK integrations](/docs/ai-observability/installation.md) redact base64 media and may truncate very long strings before capture. To capture everything in full, pass a single flag when creating your PostHog client:

PostHog AI

### Python

```python
from posthog import Posthog
posthog = Posthog(
    "<ph_project_api_key>",
    host="https://us.i.posthog.com",
    enable_full_ai_capture=True
)
```

### TypeScript

```typescript
const posthog = new PostHog(
  '<ph_project_api_key>',
  {
    host: 'https://us.i.posthog.com',
    enableFullAiCapture: true
  }
)
```

With the flag on, nothing is truncated or redacted. The one exception is [privacy mode](/docs/ai-observability/privacy-mode.md): when it's enabled, input and output content is still stripped, flag or no flag.

## Calling capture\_ai directly

If you build AI events yourself instead of using the integrations, call `capture_ai` (Python) or `captureAi` (Node) instead of `capture`. It takes the same arguments as `capture` and returns the captured event's UUID.

PostHog AI

### Python

```python
from posthog import Posthog
posthog = Posthog("<ph_project_api_key>", host="https://us.i.posthog.com")
uuid = posthog.capture_ai(
    "$ai_generation",
    distinct_id="user_123",
    properties={
        "$ai_trace_id": trace_id,
        "$ai_model": "gpt-5",
        "$ai_input": messages,
        "$ai_output_choices": choices,
    },
)
```

### TypeScript

```typescript
import { PostHog } from 'posthog-node'
const posthog = new PostHog('<ph_project_api_key>', { host: 'https://us.i.posthog.com' })
const uuid = posthog.captureAi({
  distinctId: 'user_123',
  event: '$ai_generation',
  properties: {
    $ai_trace_id: traceId,
    $ai_model: 'gpt-5',
    $ai_input: messages,
    $ai_output_choices: choices,
  },
})
```

Send content as your provider produced it, including base64 and data URIs – there's no need to reshape payloads. `capture_ai` captures exactly what you pass it, without truncating or redacting anything. [Privacy mode](/docs/ai-observability/privacy-mode.md) doesn't apply here, so leave out any content you don't want stored.

In serverless and other short-lived environments, use the awaitable variant in Node so the event is delivered before the runtime exits:

TypeScript

PostHog AI

```typescript
await posthog.captureAiImmediate({ distinctId: 'user_123', event: '$ai_generation', properties })
```

In Python, call `posthog.flush()` before exit (or enable `sync_mode`), just like with `capture`.

## Other platforms

Not on Python or Node? Build events with [manual capture](/docs/ai-observability/installation/manual-capture.md) and point your capture requests at the dedicated AI endpoint instead of the regular one – same request format, different path:

Terminal

PostHog AI

```shell
POST https://us.i.posthog.com/i/v0/ai/batch/
```

## Limits

Events up to **8MB** are accepted for now. The SDKs drop larger events before sending and log an error instead. The limit will increase as the beta continues.

### Still have questions?

Ask PostHog AI

### Was this page useful?

HelpfulCould be better