#1103 fix(mcp): point a role name that matches nothing at the node's text

What and why

• observe names a status, an alert, or a list item from its text, so an unlabelled <p role="status">Saved.</p> reads status "Saved.". A role query's name matches only the accessible name, which is empty here, so locate {role: "status", name: "Saved."} correctly finds nothing.
• The zero-match advice then sent the agent back to the observation for the accessible name, or to exact: false. Neither can work for this node, and the exact: false hint repeated even on a query that already had it.
• Each locate query now carries its own zero-match advice (packages/e2e/src/mcp/catalog.ts). A role query with a name says that observe can show a node's text in place of its name and prints the getByRole(role).filter({ hasText }) and getByText calls that match that text. The exact: false hint only shows while the query is still exact.
• Docs: the locate row in docs/reference/mcp.mdx and workflow step 2 in skills/e2e/references/mcp.md. A real accessible name still matches as before, and the content-name policy from #583 is unchanged.

Verified

Ran it locally: yes - unit level, not the MCP server against a browser (no Chromium in my environment)

• vitest run tests/unit/mcp-session.test.ts: the two new tests fail on main and pass here

main

this branch

0 nodes match getByRole("status", name: "Saved."). A test using this locator would fail with LOCATOR_NOT_FOUND. Check the accessible name in the observation (observe), or loosen the match with exact: false.

0 nodes match getByRole("status", name: "Saved."). A test using this locator would fail with LOCATOR_NOT_FOUND. A role query matches the accessible name only, and observe can show a node's text in its place (a status or alert message, a list item). If "Saved." is that text, use screen.getByRole("status").filter({ hasText: "Saved." }) or screen.getByText("Saved."). Otherwise loosen the match with exact: false.

With exact: false the last sentence is left out.

Checklist

• Changeset added (pnpm changeset) for any change to a published package, or the change is testbed, docs, or CI only.
• Breaking change: title carries !, the changeset body names what breaks and what replaces it, and the deprecation warning landed a window earlier (stability policy in CONTRIBUTING.md).
• Docs updated in the same PR: the docs/**/*.mdx page for the behavior, and skills/e2e/ if the skill describes it.
• Contract change: emitted .d.ts reviewed, tests/types/sdk-types.ts updated; wire change edits the schema and both fixtures.
• Engine contract change (e2e/engine): changesets for e2e, @e2e-dev/web, and @e2e-dev/mobile.

Fixes #1090