Error Tracking

Send errors from a custom SDK with the error ingestion endpoint. Error tracking must be enabled for the project under Settings → Features before the collector accepts reports.

EndpointCopy Anchor Link

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POST https://metrics.faststats.dev/v1/error
Authorization: Bearer <PROJECT_TOKEN>
Content-Type: application/json

The request body contains one or more errors and metadata shared by the batch:

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{
	"language": "javascript",
	"identifier": "worker-01",
	"sessionId": "session-7d3f",
	"windowId": "request-42",
	"buildId": "2026.08.16",
	"sdkName": "acme-node",
	"sdkVersion": "1.4.0",
	"context": {
		"environment": "production",
		"region": "eu-central-1"
	},
	"errors": [
		{
			"error": "TypeError",
			"message": "Cannot read properties of undefined",
			"stack": [
				"TypeError: Cannot read properties of undefined",
				"    at handleRequest (/app/server.js:42:17)"
			],
			"handled": false,
			"count": 1,
			"context": {
				"route": "/checkout"
			}
		}
	]
}

Request fieldsCopy Anchor Link

Batch fieldsCopy Anchor Link

Error fieldsCopy Anchor Link

Keep stack frames as separate array entries. The collector joins them with newlines before grouping and applying source mappings.

Supported languagesCopy Anchor Link

The language controls stack-trace normalization, grouping, and mapping. Values are case-insensitive and surrounding whitespace is ignored.

If you need support for a language not listed here, please contact us.

If language is omitted or empty, the collector uses java for backward compatibility. Any other value returns 400 Bad Request:

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{
	"error": "Unsupported language. Expected java, javascript, php, or rust"
}

ResponsesCopy Anchor Link

A report accepted into the ingestion queue returns 200 OK:

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{
	"status": "success"
}

The collector can also return:

Error responses have the shape { "error": "message" }.