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web_assertNetworkEvent

Assert that a specific event name appeared in the network traffic captured during this session.

Use this to verify that instrumentation signals, analytics events, or user-journey tracking calls actually fired when a flow was completed. The check scans request URLs and request bodies (both inlined text and on-disk blobs) for the given event name string.

Only outgoing requests (REQUEST_START phase) are checked so each network exchange is counted once regardless of how many response events accompany it.

The tool polls up to the configured timeout so it is safe to call immediately after a UI action without waiting for the browser to flush the analytics beacon. At least one scan always runs regardless of timeoutMs so passing timeoutMs=0 performs a single immediate check.

This is a test assertion — it will fail the trail if the event is not found in the network log.

Example uses: - Verify a user-journey signal fired: eventName=”adjust-stock” - Verify an analytics call was made: eventName=”checkout-started”

Source

  • Kind: class-backed
  • Class: xyz.block.trailblaze.playwright.tools.PlaywrightNativeAssertNetworkEventTool

Contract

  • Visible to LLM: yes (surface_to_llm: true)
  • Recordable: yes (is_recordable: true)
  • Host-only: no (requires_host: false)

Input schema

Required parameters

  • eventName — String The event name to search for in captured network traffic. Matched against request URLs and request body text (case-insensitive). Must not be blank.

Optional parameters

  • timeoutMs — Integer Maximum milliseconds to wait for the event to appear in captured traffic. Defaults to 5000. Increase for slow analytics pipelines. One complete scan always runs before the timeout is enforced.
  • reasoning — String

Output

Returns: string (opaque text content)

Typed result schemas (kind: query | action, MCP structuredContent) are not yet carried by the resolved manifest — this section will gain detail when that lands.