> ## Documentation Index
> Fetch the complete documentation index at: https://docs.planasonix.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Error history

> Review and diagnose errors across all pipeline executions.

**Error history** aggregates failures across pipelines so you spot recurring patterns—bad credentials, schema drift, warehouse timeouts—without opening every run individually. Pair it with **run history** when you need full context for a single execution.

## Error aggregation

The error view groups incidents by dimensions you select:

* **Error type** or **canonical code** (for example connector timeout, permission denied)
* **Pipeline** and **environment**
* **Node** or **connector** family
* **Time window**

Counts show whether an issue is **spiking** or **steady noise** from retries.

<Tip>
  Sort by **affected runs** in the last 24 hours during incidents; switch to **30 days** for backlog hygiene.
</Tip>

## Error types

Planasonix classifies errors at multiple layers:

| Layer          | Examples                                               |
| -------------- | ------------------------------------------------------ |
| Orchestration  | Schedule skipped, concurrency cap, invalid parameter   |
| Connectivity   | DNS failure, TLS handshake, proxy reset                |
| Authentication | Expired OAuth, warehouse user locked, IAM deny         |
| Data           | Type coercion, constraint violation, missing partition |
| Resource       | OOM, disk spill, slot unavailable                      |

<Info>
  Some connectors wrap vendor codes; the UI maps them to stable categories for filtering even when the raw message changes between driver versions.
</Info>

## Stack traces

When the engine captures them, failed nodes include **stack traces** or **exception chains** in the error panel. Use traces to distinguish:

* **Your** transform code bugs
* **Platform** defects (open a support case with run id)
* **Upstream** instability masked as generic socket errors

<Warning>
  Traces may contain **file paths** or **query fragments**. Share externally only through approved support channels and scrub PII.
</Warning>

## From error to fix

<Steps>
  <Step title="Open the sample run">
    Use the **latest occurrence** link to jump into run history with the failing node pre-selected.
  </Step>

  <Step title="Compare with last success">
    Diff parameters, row counts, and warehouse warehouse from the previous green run.
  </Step>

  <Step title="Check dependencies">
    Verify **connections**, **secrets rotation**, and **schema** migrations in the source system.
  </Step>

  <Step title="Document the resolution">
    Add a runbook link in the pipeline description so the next on-call engineer follows the same steps.
  </Step>
</Steps>

## Troubleshooting guides

Use these docs when errors span multiple systems or you need platform-specific depth:

<CardGroup cols={2}>
  <Card title="Diagnostics" icon="stethoscope" href="/observability/diagnostics">
    System health, tracing, and support data collection.
  </Card>

  <Card title="Dead letter queue" icon="inbox" href="/observability/dead-letter-queue">
    Recover and replay failed events in streaming paths.
  </Card>

  <Card title="Alerts" icon="bell" href="/observability/alerts">
    Route failures to on-call before users notice dashboards.
  </Card>

  <Card title="AI Copilot chat" icon="comments" href="/ai-copilot/chat">
    Ask questions grounded in your workspace context where enabled.
  </Card>
</CardGroup>

## Related topics

<Card title="Run history" icon="clock-rotate-left" href="/platform/run-history">
  Full execution list, durations, and node-level logs.
</Card>