## TL;DR
Treat the 500 as a server side transient: retry the project fetch with backoff, verify the project name against the project list, and record the request id for the platform team if it persists, because the call shape is a plain project fetch and a 500 means the API failed the request, not that the agent sent an unparseable one. Start with the Hopsworks project fetch call and the request id in the 500 response, work on one affected call, record, or run first, and prove the fix there before running the full set. Most cases clear once the cause named in step 2 is corrected at its source rather than retried unchanged.

```text
agent failed calling Hopsworks feature store API failed 500 internal error on project fetch
```

## Use this when
- You see this exact message or symptom: agent failed calling Hopsworks feature store API failed 500 internal error on project fetch
- One run, record, call, or object is affected and you can name it
- A retry without changing anything reproduces the same result

## Not for this skill when
- The system fails with a different message and none of the signals here appear
- Nothing has failed yet and you are doing first time setup or general planning
- Every service from this vendor is down for all users, which is a vendor outage to wait out first

## Steps
1. Reproduce the failure once using the Hopsworks project fetch call and the request id in the 500 response, and record the time, the workspace or account, and the one item it names. Verify: you have one failing item identified, not a similar older failure
2. Inspect the project identifier used, whether the project list call succeeds, and whether other projects fetch cleanly in the same session. Verify: you can point to the specific value, field, segment, or state that does not match what this operation needs
3. Apply the fix at that source: Treat the 500 as a server side transient: retry the project fetch with backoff, verify the project name against the project list, and record the request id for the platform team if it persists, because the call shape is a plain project fetch and a 500 means the API failed the request, not that the agent sent an unparseable one. Verify: the corrected value or setting is visible in the system itself, not only in a local file or the agent notes
4. Re-run the original operation on the single affected item first. Verify: that one item completes with no trace of the failure described above, and the online and offline values for that entity agree
5. Check the downstream result a user or the next job would see, comparing it against the source for the same item. Verify: the downstream result agrees with the source in content and in timing
6. Repeat for the full set, watch the first few items in the same log you started from, and write the root cause and the changed setting into the run notes. Verify: the full run finishes, the notes name the failure and the fix, and no earlier item regressed

## Variant phrasings
### agent failed calling Hopsworks feature store API failed 500 internal error on project fetch
The subject-first phrasing of the same failure. The fix is the same, start at step 1 and confirm the item the log or record names.
### Tool-first phrasing of this failure
The phrasing searchers use once they know which system raised it. It is the same underlying problem, not a separate bug.
### Why does this keep happening after a retry
The repeat-occurrence phrasing. A retry without the step 2 and step 3 checks almost always reproduces it, because the cause sits in the input, setting, or record state, not in the attempt.

Compatibility: Hopsworks projects API, agent tooling that enumerates projects.

## Why it happens
A 500 on a read tempts agents to rewrite the request. The useful split is one project failing (data or permissions on that project) versus every project failing (an API incident), and only the retry tells you which.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_0mrNZM9Gi9NA35LcThqHKA