n8n-node-configuration

n8n Node Configuration

Each n8n node has its own parameter shape, often with conditional fields (parameter X only matters when parameter Y has value Z). Shapes evolve between versions. Guessing produces cryptic validation errors.

Don't guess, use the get_node_types tool.

Non-negotiable

Call get_node_types with discriminators (resource, operation, mode) before configuring a node. Without discriminators you get the generic shape, missing operation-specific parameters and required fields. Build against the exact shape. Don't guess from memory.

The live get_node_types output is the canonical parameter shape. The references in this skill cover patterns, gotchas, security rules, and decision-making (when to use which operation, why credentials over text fields, engine retry caps, etc.) not parameter names or field structures. If a reference example conflicts with what get_node_types returns, trust the tool. Markdown drifts; the type def is generated from the live source.

Strong defaults

• Configure operation-first. Set resource and operation first, and conditional parameters become visible. Most "field doesn't exist" errors are really "you haven't set the parent operation yet."
• Don't carry parameters across operations. When changing operation, re-derive from the new shape. Stale parameters from the previous operation trip validation.

The flow for any new node

1. search_nodes(['<capability keyword>'])
   → returns matching node IDs + discriminators
2. Pick the right (resource, operation) for the task.
3. get_node_types([{ name: '...', resource: '...', operation: '...' }])
   → returns exact parameter shape including conditional fields
4. Build the node config from that shape.
5. validate_workflow → fix errors.
6. get_workflow_details → inspect the saved config; confirm parameters landed.
7. test_workflow with pinned data → confirm runtime behavior.

Skipping any step compounds the next. The most common skip is step 3, leading to "Cannot read property X" errors that are really "you didn't pass the discriminators."

Operation-aware configuration

Most nodes have a top-level shape like:

{
  resource: '<thing being operated on>',   // 'message', 'spreadsheet', 'user', etc.
  operation: '<verb>',                      // 'send', 'append', 'lookup', etc.
  // ...operation-specific parameters
}

The (resource, operation) pair determines what other parameters exist (e.g., Slack (message, send) differs from (user, info)).

Pattern:

1. Set resource and operation first.
2. Re-fetch get_node_types with those discriminators if you didn't initially.
3. Configure the rest from the operation-specific shape.

Property dependencies: the subtle trap

Some parameters depend on others in non-obvious ways:

• A field is required only when another field has a specific value.
• A field accepts different types depending on a mode.
• A field's options come from another field's value.

Examples:

• HTTP Request authentication: 'genericCredentialType' requires genericAuthType and credentials, but 'predefinedCredentialType' requires a different shape.
• Postgres operation: 'executeQuery' requires query, while operation: 'select' requires table and columns.
• Slack messageType: 'block' enables block-builder fields absent from messageType: 'text'.

Always inspect via get_node_types for the specific operation. Don't reuse a config from a different operation and expect it to validate.

Reference files

Per-category gotchas. Read the file for the node type you're configuring:

File	When to read
references/HTTP_NODES.md	Configuring HTTP Request: auth, pagination, query/body parameters, retries
references/WEBHOOK_NODES.md	Configuring Webhook trigger or Respond to Webhook: body parsing, response shape, async patterns
references/COMMS_NODES.md	Slack, Gmail, Discord, email: credential types, message shapes, attachments
references/DATABASE_NODES.md	Postgres, MySQL, Mongo, Supabase: query vs operation, parameter binding, error handling
references/AI_NODES.md	AI Agent node config knobs: streaming, vision, maxIterations, retries on the model sub-node. Defers design (prompts, tools, memory, structured output) to n8n-agents
references/TRIGGER_NODES.md	Webhook, Schedule, Manual, Execute Workflow Trigger: input schemas, polling vs realtime
references/SWITCH_FALLBACK.md	Configuring a Switch node: unnamed outputs / missing fallback silently drop unmatched items

Anti-patterns

Anti-pattern	What goes wrong	Fix
Building node config from memory of how the node looked last year	Parameter shape has drifted, validation fails with cryptic errors	Always get_node_types per session per node
Skipping discriminators in get_node_types	Get generic shape, miss operation-specific required fields	Always pass resource + operation (and mode where present)
Copying a node config from one operation to another and tweaking	Stale parameters trip validation, and conditional fields don't apply	Re-derive from the new operation's shape
Hardcoding tokens / credentials in node text fields	Leaks on export. See n8n-credentials-and-security	Always credentials
Not testing the node with test_workflow after configuring	Runtime errors only surface on real data	Always test with pinned data before publish