feat(mcp): add --allowed-tools and --blocked-tools options

[Yury Semikhatsky (yury-s)]

Summary

• Add --allowed-tools / --blocked-tools (PLAYWRIGHT_MCP_ALLOWED_TOOLS / PLAYWRIGHT_MCP_BLOCKED_TOOLS, allowedTools / blockedTools in config) to adjust the MCP tool set by exact name.
• --allowed-tools enables tools on top of the enabled capabilities (e.g. browser_pdf_save without --caps=pdf); --blocked-tools removes tools (e.g. browser_run_code_unsafe) and takes precedence.
• Blocked tools are hidden from tools/list and rejected on tools/call; unknown tool names fail at startup.

Fixes microsoft/playwright-mcp#1770

[github-actions]

Hi, I'm the Playwright bot and I took a first look at the CI failures.

🟢 The failures look like pre-existing flakes, not caused by this PR

All three failing tests have also failed on other PRs recently, and none of them use the new --allowed-tools / --blocked-tools filtering. Note that the MCP run was cancelled, so the report may be incomplete.

Details

This PR adds tool allow/block lists in filteredTools() and new config/CLI/env plumbing. With neither option set, the filter behaves the same as before: only core and capability-enabled tools, with skill-only tools excluded. None of the failing tests pass these options.

Pre-existing flake / infra

• [firefox] › mcp/sse.spec.ts:196 › sse transport browser lifecycle (persistent) (ubuntu): in the test-results DB it failed 2 of 348 runs on this project, on fix(tracing): do not hang on unresponsive page when capturing snapshots #42919 and fix(route): do not drop requests matching case-insensitive URLPattern #42920. The same test also fails occasionally on webkit (8/728) and chromium (5/727). It tests SSE transport and browser lifecycle, which don't depend on tool filtering.
• [msedge] › mcp/annotate.spec.ts:291 › should enter annotate mode on fresh dashboard.tsx mount with -s --annotate (windows): failed 4 of 716 runs, on chore(coverage): istanbul instrumentation for the trace viewer and html reporter #42785, chore(deps): bump the github-actions group with 2 updates #42824 and fix(net): apply socketTimeout from socket creation in httpRequest #42660, and once on a push build of main.
• [msedge] › mcp/annotate.spec.ts:316 › should annotate via direct browser_annotate MCP call (windows): failed 4 of 716 runs, on chore(coverage): istanbul instrumentation for the trace viewer and html reporter #42785, fix(har): do not hang when response extra info never arrives #42450, fix(test): unflake MCP cli-core 'click link' on Firefox #42306 and cherry-pick(#42566): feat(test): add subtitle option to test.step #42567. annotate.spec.ts flakes on Windows across every browser (for example, firefox failed 19 of 1410 runs). browser_annotate is still listed as usual, since no block list is configured.

_{Triaged by the Playwright bot - agent run}

[github-actions]

Test results for "MCP"

8809 passed, 1500 skipped

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Merge workflow run.