Self-hosted: agentOS inspector tabs (Filesystem/Processes/Terminal/System) fail; wrong gateway token, plus Safari stream bodies #2042

Environment

• Self-hosted control plane rivetdev/engine:2.3.27 (file-system storage, single node)
• agentOS worker rivetdev/services:0.2.0 on pool services (also reproduced on 0.2.1); the actor's /metadata reports {"runtime":"rivetkit","version":"2.3.16"}
• Dashboard served by the engine at /ui, signed in with the admin token
• Chrome and Safari on macOS

Steps

1. Create a VM: PUT /actors?namespace=default with {"name":"agentOS","key":"smoke-vm","runner_name_selector":"services","crash_policy":"sleep"}. v1.process.run through the gateway works.
2. Open the actor in the dashboard.

Actual

The Metadata tab works. The Filesystem, Processes, Terminal and System tabs all show:

• Chrome: Runtime error · Authentication token is invalid. · See the actor logs for the underlying error.
• Safari: Runtime error · HTTP request error: Request failed: NotSupportedError: ReadableStream uploading is not supported

Engine logs for the Chrome case:

level=warn message="Request failed" err="invalid_token: Authentication token is invalid." uri=/gateway/<actorId>@REDACTED/action/v1.vm.status
level=warn message="websocket failed" err="invalid_token: Authentication token is invalid." uri=/gateway/<actorId>@REDACTED/connect

Cause 1 (every browser): the tab uses the inspector token as the gateway token

The dashboard posts the custom tab init message as { authToken: inspectorToken, rivetToken }. This matches the contract in rivetkit/src/inspector-tab/mod.ts, where authToken is the per-actor inspector bearer token and rivetToken is the outer Rivet token.

The agentOS tab bundle served at /inspector/custom-tabs/filesystem/ builds its client from authToken (minified excerpt):

createClient({ poolName: "services", endpoint: window.location.origin, token: authToken, encoding: "bare", disableMetadataLookup: true })
  .getForId("agentOS", actorId).connect()

The engine then validates the inspector token as a gateway token and rejects it. In the same position, the admin token and a JWT from POST /auth/tokens both work:

• /gateway/<id>@<adminToken>/metadata returns 200
• /gateway/<id>@<jwt>/metadata returns 200

Suggested fix: use rivetToken for the RivetKit client, and keep authToken for Authorization: Bearer on inspector HTTP routes.

Cause 2 (Safari only): RivetKit 2.3.16 streams request bodies

rivetkit@2.3.16 engine-client/actor-http-client.ts forwards actorRequest.body (a ReadableStream) with duplex: "half". WebKit does not support streaming uploads, so every action POST throws NotSupportedError. rivet-dev/rivet 4e3fe3a16 ("send request bodies as bytes for browser clients", first released in v2.3.24) fixes this.

Suggested fix: rebuild rivetdev/services on rivetkit >= 2.3.24.

Chrome is unaffected by cause 2 only because it allows streaming uploads over HTTP/2. Firefox likely fails the same way as Safari.