> For the complete documentation index, see [llms.txt](https://lamatic.ai/llms.txt).

# Error Reference

Use this page to diagnose failed requests and Flow runs. When the API or a Flow returns an error, check the HTTP status code and the error message in the response body or in [Logs](/docs/logs), then find the matching entry below.

## HTTP status codes

| Code | Meaning | What to do |
|------|--------|------------|
| **200** | Success (check `data` / `errors` in body) | GraphQL can return 200 with errors in the body, such as `Workflow not found!`. Inspect `response.data` and `response.errors`. |
| **400** | Bad Request — invalid JSON, invalid GraphQL query, or a payload that doesn't match the trigger schema | See [GraphQL request errors](#graphql-request-errors) and check your payload against the Flow's trigger input schema. |
| **403** | Access Denied — missing or invalid API key | The API never returns 401. A missing or invalid key returns `{"errors":[{"message":"Access Denied"}]}`. Verify `Authorization: Bearer <YOUR_API_KEY>` and that the key is active in Studio → Settings → API Keys. |
| **404** | Not found — returned for credential errors | A missing Flow doesn't return 404. See [Flow not found](#flow-not-found) and [Credential errors](#credential-errors). |
| **429** | Plan quota exceeded for the last 24 hours or 30 days | Upgrade your plan or wait for the window to reset. See [Limits & Quotas](/docs/limits). |
| **500** | Server error | Retry; if it persists, check [Platform Status](https://status.lamatic.ai) and contact support. |

## Common errors and fixes

### Authentication (403)

- **Cause:** Missing or invalid API key. The API returns 403 with `{"errors":[{"message":"Access Denied"}]}`, not 401.
- **Fix:** Use the exact key from Studio → Settings → API Keys. Format: `Authorization: Bearer <YOUR_API_KEY>`. Confirm `x-project-id` matches the project that owns the Flow.

### Flow not found

A missing or invalid Flow doesn't produce an HTTP 404. The error comes back in the response body as one of:

- `Workflow not found!`
- `Invalid workflow id - <id>`

**Cause:** Wrong endpoint, project ID, or workflow/Flow ID; or the Flow isn't deployed.

**Fix:** Get the project URL and project ID from project settings. Get the workflow/Flow ID from the Flow's Connect or API panel. Deploy the Flow and use the ID of the deployed Flow.

### Payload / variable mismatch (400)

- **Cause:** The `payload` doesn't match the input schema on the GraphQL trigger (field names or types). The message starts with `Invalid trigger payload:`.
- **Fix:** Open the Flow in the Editor and check the trigger node's input schema. Align your request payload with that schema.

### Plan quota exceeded (429)

This is a plan quota, not short-term rate limiting. The message is one of:

- `Project exceeded max requests for last 30 days, max requests: X, current requests: Y. Please upgrade your plan or contact support.`
- `Project exceeded max requests for last 24 hours, max requests: X, current requests: Y. Please upgrade your plan or contact support.`

**Fix:** Upgrade your plan, or wait for the 24-hour or 30-day window to reset. Retrying with backoff won't help while the quota is exhausted. See [Limits & Quotas](/docs/limits) for plan limits.

## GraphQL request errors

Request-level errors come back in the `errors` array of the response body:

```json
{
  "errors": [
    {
      "message": "Access Denied"
    }
  ]
}
```

| Message | Status | Cause and fix |
|---------|--------|---------------|
| `Invalid JSON in request body` | 400 | The request body isn't valid JSON. Check quoting and escaping in your client. |
| `Invalid GraphQL query` | — | The query can't be parsed or validated. Check the syntax against the [GraphQL reference](/docs/interface/graphql). |
| `Query exceeds maximum allowed aliases (N)` | — | The query uses more aliases than allowed. Reduce the aliases to N or fewer. |
| `Query exceeds maximum allowed depth (N)` | — | The query nests deeper than allowed. Flatten the query to N levels or fewer. |
| `GraphQL introspection is disabled` | — | Introspection queries aren't accepted. Use the documented schema instead. |
| `Access Denied` | 403 | Missing or invalid API key. See [Authentication (403)](#authentication-403). |
| `Internal server error` | 500 | Retry. If it persists, check [Platform Status](https://status.lamatic.ai) and contact support. |

## Flow execution and log status codes

The status codes you see in Studio [Logs](/docs/logs) show what happened to a node or a Flow run. Some codes don't have their standard HTTP meaning.

| Code | Meaning in logs |
|------|-----------------|
| **200** | Node or Flow succeeded. |
| **500** | Node or Flow failed (default error code). |
| **400** | Trigger payload didn't match the GraphQL trigger's input schema. The message starts with `Invalid trigger payload: ...`. |
| **408** | Primary config timed out and the fallback config ran (fallback logic step with a timeout). |
| **509** | Node attempt failed and will be retried (Flow-level retries enabled). Also the error code for runs started via "retry flow". |
| **204** | Success on a retry attempt or a retried run. |
| **304** | Node skipped (branch not taken). |
| **208** | Node skipped during a retried run. |

Flow-level retries go up to 5, with a delay of up to 30 seconds between attempts. Each failed attempt is logged separately.

## Flow execution errors

| Message | Cause and fix |
|---------|---------------|
| `No trigger node found!` | The Flow has no trigger node. Add one and redeploy. |
| `Workflow not found!` / `Invalid workflow id - <id>` | Wrong Flow ID, or the Flow isn't deployed. See [Flow not found](#flow-not-found). |
| `Invalid trigger payload: <details>` | The request payload doesn't match the advanced schema on the GraphQL trigger. Status 400. |
| `Max retries reached for node <nodeId>` | The node failed every Flow-level retry. Check that node's own error in the logs. |
| `Timeout after <n>ms` | The primary config exceeded the fallback timeout, so the fallback config ran. |
| `All parallel requests failed` | Every config in a parallel logic step failed. |
| `All logic steps failed` | Every configured logic step (retry, fallback, parallel, A/B) failed for the node. |
| `Unsupported step type: <type>` / `Invalid step` | A logic step is misconfigured on the node. Review the node's [logic configuration](/docs/nodes/node-logic). |
| `Previous request id is required` | You used "retry from failed node" without the original request ID. Provide the request ID of the failed run. |
| `Cache not found, please reach out to lamatic support` | Platform-side error. Contact support. |

## Credential errors

| Message | Status | Cause and fix |
|---------|--------|---------------|
| `credentialId is required` / `Invalid credentialId` | 400 | The request is missing a credential ID, or the ID is malformed. Provide a valid `credentialId`. |
| `Credential not found or not accessible` | 404 | The credential doesn't exist or belongs to another project. These two cases are deliberately indistinguishable. Confirm the ID and that the credential is in the same project as the Flow. |
| `Credential resolution is not available for this project, please contact support` | 500 | Platform-side. Contact support. |

## Reading an error in the logs

When a Flow run fails, open the run in [Logs](/docs/logs) and check these fields:

- **`errorMsg`**: The error message.
- **`failedNode`**: The node that failed. It includes `nodeId`, `nodeName`, `nodeSlug`, and `loopBatchId` if the node ran inside a loop or batch.
- **`logicStep`** (on node logs): Which logic step produced the failure. For example:
  - `retry (attempt 2/3 with Config B)`
  - `parallel (Config A)`
  - `abTest (selected Config B)`
  - `fallback (Config A timed out)`

## Node-specific errors

Most errors in logs come from individual nodes, such as integration, LLM, code, and API nodes. They're shown verbatim in `errorMsg` together with `failedNode`. Common categories are:

- Integration authentication or credential failures
- Upstream HTTP errors, shown as `HTTP <status>: <body>`
- [Code node](/docs/nodes/logic/code-node) runtime errors

For node configuration and requirements, see the per-node docs, such as the [API node](/docs/nodes/data/api-node), [Generate Text node](/docs/nodes/ai/generate-text-node), and the full [Nodes](/docs/nodes) list.

## Flow failures: next steps

If the request succeeds but the Flow run fails:

- Check **Logs** in Studio for the run's trace and the failing node.
- Use the **Feedback API** or **Reports** if you're capturing run outcomes.
- See the node's documentation for required config (e.g. model credentials, input shape).

---

*If you hit an error not listed here, check [Limits & Quotas](/docs/limits) and [Support](https://support.lamatic.ai) or community Slack.*