fix(frontend): treat undefined input as empty

[abcxff]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[railway-app]

🚅 Deployed to the rivet-pr-4536 environment in rivet-frontend

Service	Status	Web	Updated (UTC)
frontend-inspector	😴 Sleeping (View Logs)	Web	Mar 31, 2026 at 4:49 am
website	😴 Sleeping (View Logs)	Web	Mar 31, 2026 at 4:49 am
frontend-cloud	😴 Sleeping (View Logs)	Web	Mar 31, 2026 at 4:49 am
mcp-hub	✅ Success (View Logs)	Web	Mar 31, 2026 at 4:38 am
ladle	❌ Build Failed (View Logs)	Web	Mar 31, 2026 at 4:38 am
kitchen-sink	❌ Build Failed (View Logs)	Web	Mar 31, 2026 at 4:38 am

[abcxff]

• fix(frontend): treat undefined input as empty #4536 👈 (View in Graphite)
• main

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[claude]

PR Review: fix(frontend): treat undefined input as empty

Summary: This is a correct and minimal fix. When data.input is undefined/falsy, the previous code would call btoa(JSON.stringify(undefined)) which produces "dW5kZWZpbmVk" (base64 of the string "undefined"), sending unexpected data to the API instead of omitting the field.

The Fix is Correct

The change correctly leaves input as undefined when not provided, so the API call omits the field entirely rather than encoding a nonsensical value.

Minor Consideration

The falsy check (data.input ?) would also skip encoding for an empty string "", 0, or false. Since input here is actor initialization data (likely an object or null), this is fine in practice. If the type allows non-object falsy values as valid inputs, data.input != null would be marginally more precise — but given the domain context (actor input payload is a JSON-serializable object), this is a non-issue.

Verdict

LGTM. The change is correct and addresses a real bug where actors without explicit input would receive a garbled base64-encoded "undefined" string instead of omitting the field.

[pkg-pr-new]

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commit: 0bffbe5