Radarr/Sonarr Tag Creation Fails with 400 Error Due to Invalid Tag Format

[rancur]

Description

Overseerr attempts to create requester tags in Radarr/Sonarr using the format "{userId} - {username}" (e.g., "10 - Ryan Y"), but Radarr and Sonarr now enforce strict validation rules that only allow lowercase letters (a-z), numbers (0-9), and hyphens (-). Tags containing spaces or uppercase letters are rejected with a 400 Bad Request error.

Version

1.34.0 (Linuxserver.io v1.34.0-ls154)

Steps to Reproduce

1. Configure Overseerr with Radarr/Sonarr integration
2. Enable "Tag Requests" in Overseerr settings
3. Have a user (e.g., user ID 10, username "Ryan Y") request content
4. Overseerr attempts to create tag "10 - Ryan Y" in Radarr
5. Radarr rejects the tag with 400 error: "Allowed characters a-z, 0-9 and -"

Expected Behavior

Overseerr should create tags that comply with Radarr/Sonarr's validation rules, or use existing tags that match the requester.

Actual Behavior

• Overseerr tries to create tags with format: "{userId} - {username}"
• Radarr/Sonarr reject tags containing spaces and uppercase letters
• Request processing fails or continues without proper tagging
• Error in logs: [Radarr] Failed to create tag: Request failed with status code 400

Screenshots

No response

Logs

### Overseerr Error Logs
2025-12-21T19:40:45.866Z [info][Media Request]: Requester has no active tag. Creating new {"requestId":531,"mediaId":1282,"userId":10,"newTag":"10 - Ryan Y"}
2025-12-21T19:40:45.911Z [error][Media Request]: Something went wrong sending request to Radarr {"errorMessage":"[Radarr] Failed to create tag: Request failed with status code 400","requestId":531,"mediaId":1282}

Radarr logs show:
[Warn] RadarrErrorPipeline: Invalid request Validation failed:
-- Label: Allowed characters a-z, 0-9 and -

Platform

desktop

Device

Docker container

Operating System

Linux - Docker (Linuxserver.io image)

Browser

Any

Additional Context

• Radarr Version: Latest (validation rule: ^[a-z0-9-]+$)

Workaround

Temporarily disabled automatic tagging by setting tagRequests: false in Overseerr settings. This allows requests to proceed but loses the tagging functionality.

Related Issues

• Similar issue in Jellyseerr (Overseerr fork): tags for sonarr/radarr no longer work with spaces seerr-team/seerr#1940

Suggested Solution

1. Modify tag format to comply with Radarr/Sonarr validation (e.g., "{userId}-{username-lowercase}" → "10-ryan-y")
2. Add configuration option to customize tag format
3. Check for existing tags before creating new ones
4. Handle tag creation failures more gracefully (fallback or skip tagging)

Additional Context

• Radarr's tag validation regex: ^[a-z0-9-]+$
• Existing tags in Radarr with spaces/uppercase were likely created before validation was enforced
• Manual tag creation with valid format (e.g., "10-ryan-y") works correctly

Code of Conduct

• I agree to follow Overseerr's Code of Conduct

[gianfelicevincenzo]

Same error...

[nico22nguyen]

Same issue here

[earywen]

Same issue here

[danaimone]

Also experiencing this issue.

[Knuspel]

Maybe, if possible, this is a good step to also just allow the selection of which tag is being used and what it is structured as. :)

[danaimone]

Maybe, if possible, this is a good step to also just allow the selection of which tag is being used and what it is structured as. :)

Agree, seems odd that this isn't customizable

[jnko266]

Same problem for me

[rjwinks]

I'm also having this issue

[mcagriardic]

I am currently using this workaround - https://www.reddit.com/r/radarr/comments/1ns9fiu/comment/nw8r42b/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button