Browser capability · first usable slice

WebMCP, inside SYNAL.

This is a working test page, not another browser-agent product. It exposes a safe read-only tool, checks whether the browser can discover and execute it, verifies the result against the actual page, and keeps a DOM fallback when WebMCP is unavailable.

Test boundaries: local demo data only. No account credentials, network calls, analytics or persistence. This lab does not claim that an external agent will automatically consume WebMCP tools; that depends on the agent/browser integration.

01 · Provider

Tool exposed by this page

The page registers synal_get_lab_status through the current document.modelContext API where available.

Fixture record
READY
SYNAL WebMCP test fixture is ready for read-only inspection.

Checking browser API…Tool not registered

Initialising provider…

02 · Consumer / verification

Discover, call, verify

The in-page harness uses getTools() and executeTool() when the browser exposes them. It compares the tool response with the rendered DOM state.

Not runNot verified

No test has run yet.

03 · Evidence

Execution receipt

Each run records the method, discovered tool names (if available), returned value, observed DOM value, and whether they matched. The receipt exists in this page session only.

No receipt yet.

Next compatibility tests

What this lab enables

First-party tool provider: this page publishes its own test tool.
Consumer contract: discover and execute locally where the API permits.
Fallback: read the visible DOM without WebMCP.
Verification: compare returned data with the page's actual state.
Next slice: extension-side integration and a separate-origin test page to validate cross-origin constraints.

WebMCP is experimental and the API can change. This lab intentionally checks capability at runtime instead of assuming support.