Record and query browser_performance_observed
Document what each browser_performance_observed row represents and which service sends it. Send test events to check the fields, then verify that the query answers your question.
- 1
Outcome becomes final
Browser instrumentation after a performance measurement settles emits only when a reviewed web vital or application navigation measurement becomes final.
- 2
Choose the fields
8 required fields preserve the declared grain: One sampled browser metric observation.
- 3
Check the test event
Check types, UTC time, alternate outcomes, idempotency, and every pseudonymous or review-classified field.
- 4
Query the result
Which routes, releases, and device classes have degraded user-visible performance?
Grain
One sampled browser metric observation.
Owner
Browser instrumentation after a performance measurement settles
Emit when
When a reviewed Web Vital or application navigation measurement becomes final.
Field contract
Field types and data to exclude
Keep field names and types stable once production queries depend on them. Document optional fields and add them only when they answer a specific question.
| Field | Type | Required | Privacy | Meaning |
|---|---|---|---|---|
| timestamp_utc | timestamp | yes | non-sensitive | UTC time when the operation finishes. |
| event_id | string | yes | non-sensitive | Stable unique identifier used for deduplication. |
| release | string | yes | non-sensitive | Application or service version that emitted the event. |
| session_id | string | yes | pseudonymous | Rotating, privacy-reviewed browser session identifier. |
| route_template | string | yes | non-sensitive | Normalized route without query strings or identifiers. |
| metric_name | string | yes | non-sensitive | Bounded metric such as LCP, INP, CLS, or navigation_ms. |
| metric_value | number | yes | non-sensitive | Numeric value in the unit defined by metric_name. |
| sample_rate | number | yes | non-sensitive | Selection probability used for this observation. |
Synthetic JSON event
{
"timestamp_utc": "2026-07-29T09:18:11Z",
"event_id": "evt_browser_01",
"release": "2026.07.3",
"session_id": "browser_session_71a2",
"route_template": "/team/:team/dashboard/:dashboard",
"metric_name": "LCP",
"metric_value": 2180,
"sample_rate": 0.1
}Privacy review
Review identifiers before ingestion
This example uses synthetic identifiers. Pseudonymous values can still be personal data, and review fields can expose business or provider context. Apply your own consent, retention, access, residency, and deletion requirements.
session_id: pseudonymous
Validation checklist
Test the schema before building a dashboard
- Send one known browser_performance_observed fixture after the documented outcome boundary.
- Verify all 8 required fields arrive with the documented types.
- Retry the same event identifier and confirm the chosen deduplication behavior.
- Send a controlled failure or alternate outcome when the workflow supports one.
- Run the related SQL over a fixed window and reconcile the result to the fixture.
Common mistakes
Record one result per row
- Emitting browser_performance_observed before browser instrumentation after a performance measurement settles knows the final outcome.
- Mixing different kinds of results in one table, which makes counts and rates ambiguous.
- Replacing controlled categories with raw URLs, payloads, prompts, or error text.
- Changing a field type in place after saved queries and dashboards depend on it.
- Adding identifiers without a documented investigation, access, and retention need.
Use the contract
Query the event and set up monitoring
Related contracts
Send a test event before production traffic
Create a free API key, send the synthetic event, and inspect the inferred table before connecting a live workflow.