This proof signs a Browserbase MCP shaped browser session through @atrib/mcp-wrap.
start -> navigate -> observe -> act -> extract -> end
- Upstream surface: Browserbase hosted Streamable HTTP MCP endpoint.
- atrib path:
@atrib/mcp-wraparound a hosted Streamable HTTP MCP upstream. - Control path:
browserbase-action-gate-v0signs theactdecision and outcome before the Browserbase action runs. - Record policy: public records keep tool names plus
args_hashandresult_hash. - Verification:
@atrib/mcpverifies each Ed25519 record signature after the wrapper writes its mirror. - Log proof: accepted records were submitted to
https://log.atrib.dev/v1/entriesafter full-flow verification; inclusion was verified. - Publish policy:
accepted-run-after-verification
| Tool | Record hash | Public log index |
|---|---|---|
| start | sha256:3fec4c4fe89b52120116e10df30738e735305622a5d11b5e6a58044bd79c8a35 | 69802 |
| navigate | sha256:310c9186053fc9aca97c18535634862e1698d29e94f10e611ededca406a349fd | 69803 |
| observe | sha256:afb2d48ba555b06efd1ea7feaf052a0e630f8bb57167990782d0ade5c383030a | 69804 |
| act | sha256:3afb35ced45576a91d7b870520adfeab16a8e20503eef8527c0b313cd2eea5c3 | 69805 |
| extract | sha256:4dd3490d3eaed99cd2abc4ea112cf8d87970d9f591e5c73c0366c5cf270ccb85 | 69806 |
| end | sha256:9a9a4833f9df89deb95742d8a61781695fe2435e514b688fd7b9efcc033dbf8c | 69807 |
Representative public links:
- Explorer: https://explore.atrib.dev/action/sha256:3fec4c4fe89b52120116e10df30738e735305622a5d11b5e6a58044bd79c8a35
- Log proof: https://log.atrib.dev/v1/proof/3fec4c4fe89b52120116e10df30738e735305622a5d11b5e6a58044bd79c8a35
The runner evaluates browserbase-action-gate-v0 before act. The decision
record is signed before the Browserbase tool call. If the decision is block
or escalate, the runner stops before act and closes the session with
end when possible.
| Tool | Decision | Decision record | Decision index | Outcome record | Outcome index |
|---|---|---|---|---|---|
| act | allow | sha256:f69c1470d23ffc99eff13b53b9b623770db6671a72596683dfe925e1af16c113 | 69808 | sha256:d5ea20d9ef67977ba3d37dc1c1579fbc2c121d8ee160e9fa8a17b3bfd0874c0a | 69809 |
- Policy event type:
https://browserbase-action-gate.atrib.dev/v1/decision - Stopped before: none
- Blocked tool executed: false
The wrapper saw private Browserbase-shaped payloads: session id, replay URL,
page snapshot, selector, form value, and extracted page text. The action policy
also saw target, action, and observed-state inputs. The public artifact stores
only hashes or public fixed instructions for those fields. See
redaction-manifest.json.
This proof run signs the wrapper path, record chain, hash-only disclosure, public log inclusion, verifier path, real Browserbase MCP command path, and signed action-policy records. It still keeps Browserbase Live View and replay material private. Hosted Browserbase MCP can return temporary model-capacity errors; public publication starts only after the full six-step flow verifies.
This is a fixed proof artifact plus a rerunnable local command. The resettable
demo server lives in
packages/integration/examples/browserbase-stagehand/live-demo/ and is deployed
at https://atrib-browserbase-stagehand-demo.fly.dev/. The demo page shows the
agent-ready WebMCP target app that Browserbase controls, Stagehand observe,
act, and extract workflow, cursor/click playback, and atrib action-gate
receipts side by side. Fixture playback is deterministic. Live Browserbase
inspection refs, when present, are shown only as UI links and stay out of the
public proof artifact.
ATRIB_BROWSERBASE_STAGEHAND_LIVE=1 \
ATRIB_BROWSERBASE_UPSTREAM=hosted \
ATRIB_PACKET_PUBLIC_LOG=1 \
BROWSERBASE_API_KEY=... \
ATRIB_PACKET_WRITE_ARTIFACTS=1 \
pnpm --filter @atrib/integration browserbase-stagehand-packetATRIB_BROWSERBASE_STAGEHAND_LIVE=1 \
ATRIB_PACKET_PUBLIC_LOG=1 \
BROWSERBASE_API_KEY=... \
BROWSERBASE_PROJECT_ID=... \
GEMINI_API_KEY=... \
ATRIB_PACKET_WRITE_ARTIFACTS=1 \
pnpm --filter @atrib/integration browserbase-stagehand-packet