fix(core): Validate non-empty prompts in AI vendor nodes before API calls (backport to release-candidate/2.21.x)#30820
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alexander-gekov merged 1 commit intoMay 20, 2026
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Bundle ReportChanges will decrease total bundle size by 8.44kB (-0.02%) ⬇️. This is within the configured threshold ✅ Detailed changes
Affected Assets, Files, and Routes:view changes for bundle: editor-ui-esmAssets Changed:
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1 issue found across 22 files
Architecture diagram
sequenceDiagram
participant WF as Workflow Engine
participant NV as AI Vendor Node
participant PV as Prompt Validator
participant API as Upstream AI API
Note over WF,API: NEW: Prompt validation before external API calls
WF->>NV: execute(i)
NV->>NV: Extract node parameters (modelId, prompt/text, options, etc.)
alt Text/Message Operations (Anthropic, Gemini, OpenAI v1/v2)
NV->>PV: validateMessages(messages, addAttachments)
PV->>PV: Filter out empty/whitespace-only messages
alt No non-empty messages AND no attachments
PV-->>NV: throw NodeOperationError("A non-empty prompt is required.")
else Has valid content
PV-->>NV: Return filtered messages
end
else Image/Video Generate Operations (all vendors)
NV->>PV: validatePrompt(prompt)
PV->>PV: Check prompt.trim() is non-empty
alt Prompt empty or whitespace-only
PV-->>NV: throw NodeOperationError("A non-empty prompt is required.")
else Valid prompt
PV-->>NV: Continue
end
else Analyze Operations (all vendors via baseAnalyze.ts)
NV->>PV: validateText(text)
PV->>PV: Check text.trim() is non-empty
alt Text empty or whitespace-only
PV-->>NV: throw NodeOperationError("A non-empty prompt is required.")
else Valid text
PV-->>NV: Continue
end
end
alt Validation PASSED
NV->>API: Make AI provider request (HTTP/HTTPS)
API-->>NV: Return AI response (success/error)
NV-->>WF: Return execution data
else Validation FAILED
NV-->>WF: NodeOperationError with itemIndex
Note over WF: Workflow fails fast at node level<br/>No API call made, no resource waste
end
Note over NV,PV: Special case: Anthropic allows empty messages when attachments are present
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Fix all with cubic | Re-trigger cubic
Codecov Report✅ All modified and coverable lines are covered by tests. 📢 Thoughts on this report? Let us know! |
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Performance ComparisonComparing current → latest master → 14-day baseline docker-stats
Idle baseline with Instance AI module loaded
Memory consumption baseline with starter plan resources
How to read this table
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Description
Backport of #30795 to
release-candidate/2.21.x.Checklist for the author (@alexander-gekov) to go through.
After this PR has been merged, it will be picked up in the next patch release for release track.
Original description
Summary
AI vendor nodes (Google Gemini, OpenAI, Anthropic) did not validate that user prompts are non-empty before sending requests to upstream APIs. Empty or whitespace-only prompts result in wasted API round-trips (400 errors from providers) and, when routed through the AI Gateway, waste proxy resources without any budget deduction.
This PR adds
trim() + empty checkwithNodeOperationErrorin each operation'sexecute()before the API call, ensuring workflows fail fast at the node level with a clear error message.Changes
Text message operations (Priority 1):
Generation operations (Priority 2):
Analyze operations (Priority 3):
baseAnalyze.tsbaseAnalyze.tsHow to test
NodeOperationErrorwith message "A non-empty prompt is required." instead of making an API callRelated Linear tickets, Github issues, and Community forum posts
https://linear.app/n8n/issue/NODE-5096
Review / Merge checklist
Backport to Beta,Backport to Stable, orBackport to v1(if the PR is an urgent fix that needs to be backported)🤖 PR Summary generated by AI
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