fix: don't misroute telemetry/events to the browser VM#126
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The direct-to-VM routing allowlist matched on the subresource SEGMENT
("telemetry"), so the new historical GET /browsers/{id}/telemetry/events
endpoint (served by the control plane from S2) was routed to the session VM —
which only serves the live telemetry/stream SSE — once a session was route-cached,
yielding failures / wrong data.
Fix the granularity:
- Allowlist entries are now full path-prefixes ("curl", "telemetry/stream")
instead of bare subresources.
- Matching is segment-boundary aware: "telemetry/stream" matches
"telemetry/stream[/...]" but NOT "telemetry/events" or "telemetry/streamfoo".
- Safe by default: any path not in the allowlist (including future browser
sub-endpoints) goes to the control plane — slower, never misrouted.
All in lib/ (Stainless-preserved custom code), so durable across regens. Adds a
regression vector pinning stream->VM, events->control-plane, the boundary guard,
curl->VM, and non-allowlisted->control-plane.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
CI 'test' failed because two root-package assertions still referenced the old "telemetry" segment after the default allowlist changed to ["curl","telemetry/stream"]: - TestBrowserRoutingSubresourcesFromEnvDefaultsToCurl: default assertion - TestBrowserRoutingRewritesTelemetryStreamToVM: env override aligned to the full-path value it now exercises go test ./... passes. The lib/browserrouting matcher test already covers telemetry/events -> control plane. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
archandatta
approved these changes
Jun 24, 2026
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The direct-to-VM routing allowlist matched on the subresource segment (
telemetry), so the new historicalGET /browsers/{id}/telemetry/events(served by the control plane from S2) was routed to the session VM (which only serves the livetelemetry/streamSSE) once a session was route-cached → failures/wrong data.Fix (in
lib/, Stainless-preserved → durable across regens):curl,telemetry/stream), not bare subresources.telemetry/streammatchestelemetry/stream[/...]but NOTtelemetry/eventsortelemetry/streamfoo.Should land in 0.70.0, which introduces
telemetry/events. Companion PRs in kernel-node-sdk + kernel-python-sdk apply the same change.🤖 Generated with Claude Code
Note
Medium Risk
Changes request routing for all browser subresources when route cache is warm; wrong matching would break telemetry/events or SSE, but behavior is narrowly scoped with strong test coverage.
Overview
Fixes misrouting of historical telemetry reads when a browser session route is cached. Allowlisting the bare
telemetrysegment sentGET .../telemetry/events(control plane / S2) to the VM, which only serves live SSE attelemetry/stream.Direct-to-VM routing now uses path-prefix allowlist entries (
curl,telemetry/streamby default) with segment-boundary matching viamatchesDirectVMPrefix:telemetry/streamand subpaths route to the VM;telemetry/events, baretelemetry, and similar paths stay on the control plane. Env overrideKERNEL_BROWSER_ROUTING_SUBRESOURCESfollows the same prefix semantics.Regression tests pin stream→VM, events→control plane, boundary cases, and updated defaults.
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