4 min readUpdated Mar 2, 2026

API Builder — Troubleshooting & Glossary

Common issues you may encounter when building or using custom API integrations, plus a quick-reference glossary of technical terms.


Troubleshooting

IssueWhy It HappensSolution
"Invalid JSON" when analyzingThe pasted JSON has syntax errors — trailing commas, missing quotes, or single quotes instead of double.Validate your JSON at jsonlint.com before pasting.
Endpoint returns empty dataThe Root Accessor doesn't match the response, or JSON paths are wrong.Test the API manually first. Compare the actual response structure to your configured paths.
Auth errors at runtimeCredentials are incorrect, expired, or the auth type doesn't match what the API expects.Verify credentials in the API provider's dashboard. Confirm the auth method matches the docs.
Can't find the integration in workflowsThe definition is saved, but no credentials have been added.Go to Integrations, find your integration, and add credentials.
Parameter not recognized by APIThe parameter name doesn't match the API's expected name exactly (casing matters).Check the API docs for exact parameter names. userIduser_id.
"Unauthorized" errorThe API key or token doesn't have permission for this endpoint, or the wrong header is being used.Check that your key has the required permissions/scopes. Verify the auth header name matches the API docs.
Array data comes back as single itemThe response path uses [0] instead of [*].Edit the output field's Source JSON Path and replace [0] with [*].
Fields have confusing auto-generated namesMultiple fields have similar names, causing prepended prefixes.Edit the Node Output Label to any name that makes sense for your workflow.

Glossary

TermDefinition
API (Application Programming Interface)A set of rules that lets two systems communicate. In this context, a web API that accepts HTTP requests and returns data.
REST (Representational State Transfer)An architectural style for APIs that uses standard HTTP methods and URLs to access resources.
EndpointA specific URL path + HTTP method combination that performs one operation (e.g., GET /users).
Base URLThe root address of an API, shared by all its endpoints (e.g., https://api.example.com/v1).
HTTP MethodThe action type of a request: GET (read), POST (create), PUT (update), DELETE (remove).
JSON (JavaScript Object Notation)A text-based data format using key-value pairs, objects {}, and arrays []. The standard response format for REST APIs.
Path ParameterA variable embedded in the URL path, wrapped in curly braces: /users/{id}.
Query ParameterA key-value pair appended to the URL after ?: /users?limit=10.
Bearer TokenAn access token sent in the Authorization: Bearer <token> header. Common in OAuth 2.0 flows.
API KeyA unique string that identifies and authorizes your application when calling an API.
Root AccessorA JSON path that tells the system where the actual data starts inside a wrapper object.
Leaf FieldA JSON value that is not an object or array — a string, number, or boolean. The actual data you extract.
Group FieldA JSON object or array that contains other fields.
Wildcard [*]In JSON path notation, means "every item in this array" — used to extract a field from every element.
Credential SchemaThe template that determines what fields are shown when a user adds credentials (API key, token, or username/password).

GoalGuide
See all built-in integrationsIntegrations
Learn about workflow nodesWorkflow Nodes
Understand AI workflow nodesAI Platform Features
Manage token costs for AIUsage & Tokens
Security & data handlingSecurity & Privacy
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