# starlette.exceptions.HTTPException: 404: Not Found

- **ID:** `python/starlette-http-exception`
- **Domain:** python
- **Category:** runtime_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

A route or resource is not found; raised by Starlette when no matching route exists.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 0.30.x | active | — | — |
| 0.40.x | active | — | — |

## Workarounds

1. **** (95% success)
   ```
   Check `app.routes` or the OpenAPI docs at /docs.
   ```
2. **** (90% success)
   ```
   app.include_router(router, prefix='/api/v1')
   ```

## Dead Ends

- **** — Masks the 404 but doesn't fix the missing route or typo. (70% fail)
- **** — Debug mode shows traceback but doesn't resolve missing route. (90% fail)