Inconsistent thumbnail size handling across endpoints

[M_etrics]

Affected Service

Roblox Cloud Services – Thumbnails API

Endpoints

• /v1/assets
• /v1/game-passes
• /v1/developer-products/icons

---

Summary

Thumbnail size handling is inconsistent across endpoints.

• /v1/assets accepts 1440x456 and returns a valid image.
• /v1/game-passes and /v1/developer-products/icons reject the same size as invalid.

This inconsistency breaks uniformity across the API and forces developers to implement special-case logic for each endpoint.

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Steps to Reproduce

1. Working Request (Assets API)

   GET /v1/assets?assetIds= 1345315789&returnPolicy=PlaceHolder&size=1440x456&format=Png&isCircular=false
   

   Response: 200 OK
   Returns a valid thumbnail.
   *Screenshot:
   

   

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2. Failing Request (Game Passes API)

   GET /v1/game-passes?gamePassIds=1345315789&size=1440x456&format=Png&isCircular=false
   

   Response: 400 Bad Request

   {
     "errors": [
       {
         "code": 3,
         "message": "The requested size is invalid. Please see documentation for valid thumbnail size parameter name and format.",
         "field": "size"
       }
     ]
   }
   

---

3. Failing Request (Developer Products API)

   GET /v1/developer-products/icons?developerProductIds=1321074632&size=1440x456&format=Png&isCircular=false
   

   Response: 400 Bad Request

   {
     "errors": [
       {
         "code": 3,
         "message": "The requested size is invalid. Please see documentation for valid thumbnail size parameter name and format.",
         "field": "size"
       }
     ]
   }
   

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4. Successful Request (Game Passes API, Smaller Size)

   GET /v1/game-passes?gamePassIds=1345315789&size=150x150&format=Png&isCircular=false
   

   Response: 200 OK
   Returns a valid thumbnail (150x150).
   

   

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Actual Behavior

• /v1/assets → accepts 1440x456.
• /v1/game-passes → rejects 1440x456.
• /v1/developer-products/icons → rejects 1440x456.

---

Impact

• Developers cannot reuse the same thumbnail size logic across resources.
• Requires extra handling and conditional logic per endpoint.
• Causes confusion due to undocumented differences in valid sizes.

---

Suggested Fix

• Standardise valid thumbnail sizes across all endpoints (assets, game-passes, developer-products, etc.).

Expected behavior

• All thumbnail endpoints should support the same set of valid sizes (e.g., 1440x456).
• If endpoint-specific restrictions exist, documentation should clearly specify the valid sizes per endpoint.

[Hooksmith]

Hey, we don’t intend for sizes to work across endpoints like this, so this should not be reported as a bug. I also question whether it makes sense at all to request a non-square thumbnail for game passes and developer products. I would consider that more an unintended feature of the generic asset endpoint than anything else.

I recommend filing this as a feature request explaining what problem you are trying to solve. The problem statement here (asking for a rectangular thumbnail for assets that are normally circular/square) doesn’t seem warranted at a glance, without further information on what you’re trying to achieve.

When filing your feature request, please focus on problem rather than proposed solution. Your feature request should e.g. not be titled “allow various thumbnail sizes against all these endpoints”, it should be related to your actual problem that makes you believe you need this feature.

[M_etrics]

Thanks @Hooksmith

I will review the need for a feature request post