n8n-connections
n8n Connections
n8n's SDK has a small connection grammar. Two of its shapes silently produce broken workflows that pass validation. This skill is mostly about not falling into those traps.
The non-negotiable: the .to() trap
.to() must go inside .add(), not after.
.add(node.output(0)).to(target) // ❌ connection silently dropped
.add(node.output(0).to(target)) // ✅
validate_workflow does not catch this. The workflow validates, publishes, and runs without the wire. The bug looks identical to a misconfigured or "not firing" node.
If you've written .add(...).to(...) outside the parens, you have a bug. No exceptions.
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4n8n-debugging
Use when an n8n workflow isn't working, errors appear, results don't match what was expected, or the user says "this isn't working." Triggers on errors, unexpected output, "it's not working", "why is this happening", "the workflow stopped", failure investigation, or any debugging context.
4n8n-code-nodes
Use when the user reaches for a Code node, mentions writing JavaScript or Python in n8n, or any custom logic comes up in workflow design. Triggers on "Code node", "Code", "JavaScript", "Python", "custom logic", "transform data", "$input", "$json transformation", "loop in code", "write a function", or any time the obvious answer seems to be "just put it in code.
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Use when working with n8n's built-in Data Tables, designing schemas, inserting/updating/upserting rows, deduping, or querying. Triggers on "Data Table", "data table", `n8n-nodes-base.dataTable`, "dedup", "idempotency", "lookup", "persistent state", "store across executions", or any schema design discussion inside n8n.
4n8n-binary-and-data
Use when handling files, images, attachments, or binary data in n8n, OR when an AI agent needs to take a user-uploaded file as tool input or return a generated file. For Data Tables (schemas, dedup, persistent state), see the separate n8n-data-tables skill. Triggers on "file", "image", "PDF", "attachment", "binary", "upload", "download", chat trigger with files, agent tool that needs a file, vision/multimodal, or any handling of non-JSON file data.
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