## TL;DR
Look for the run in the right namespace and pipeline: Kubeflow run lookups are scoped, so confirm the experiment name, the namespace, and the pipeline run id belong together before concluding the run is gone. A run id copied from another namespace, or an experiment name used where a run id belongs, returns not found even though the run exists and may still be executing.

```text
Kubeflow pipeline run failed error "Run is not found in experiment namespace"
```

## Use this when
- The check or run fails with this symptom: a Kubeflow pipeline run fails with Run is not found in experiment namespace.
- You are working on a Kubeflow Pipelines deployment where runs are organised by experiment and namespace and the failure repeats on the same data or configuration.
- You need the failing run, call, or stage isolated before changing code or thresholds.

## Not for this skill when
- A run that was deleted by retention, which is genuinely absent and needs its artifacts recovered from storage instead.
- The error text names a different tool, stage, or root cause. Match the verbatim error first and use that skill.

## Steps
1. List runs in the namespace without a name filter and find the run by its job or pipeline name. Verify: the run appears, or it truly is absent
2. Compare the experiment name and namespace in the failing call with the run actual location. Verify: the mismatch is identified
3. Correct the call to use the run id from the submission response for that namespace. Verify: the lookup returns the run
4. Store the submission response, including run id and namespace, with the pipeline record. Verify: later lookups use the stored pair
5. Rerun the status check. Verify: the run status returns normally

## Variant phrasings
### kubeflow run is not found in experiment namespace
The shorter phrasing focused on the named failure.
### kubeflow pipeline run failed not found error
The symptom phrasing a searcher tries next.
### kubeflow run namespace lookup fix
The variant naming the failing stage or tool directly.

Compatibility: Kubeflow Pipelines 2.x experiments, namespaces, and run APIs

## Why it happens
Kubeflow scopes runs under experiments inside namespaces, and multi-team deployments reuse pipeline names across both. Code that assumes the default namespace, or that treats an experiment name as a run identifier, produces not found errors for healthy runs.

## Edge cases / pitfalls
- Run names are display strings and are not unique; always address runs by id plus namespace.
- Retention policies delete old runs from the UI while their artifacts remain in object storage; check storage before reporting a run lost.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_kIKgH7-ow-rIg-0wkAL6-g