Chrome DevTools MCP vs Kernel

Chrome DevTools MCP 83

Scored as a local stdio package. Official npm package, 1.12.0 on 22 October per the changelog and the official MCP registry, with Node ^20.19, ^22.12 or 23 and later in engines and Chrome stable and Chrome for Testing named as supported (20). Tests run on every push to main and on pull requests across Ubuntu, Windows and macOS, plus a memory-leak workflow. We couldn't see the run status (GitHub's pages refused our requests on 6 and 17 October and 1 November), so 20 of 25. 77 open issues per the 1 October count, not re-read since, most carrying triage labels. Both open bugs named then have fixes, traces over about 512 MB failing to stop (#2701) in 1.10.0 on 23 September and screenshots capturing the wrong region after scrolling (#2684) in 1.11.0 on 15 October (#2685), and 1.12.0 lists 51 fixes (18). release-please writes the changelog from conventional commits, but 1.8.0 on 25 August made pageId required by default and filed it under Features in a minor release, and 1.11.0 turned the screencast tools on by default, also as a feature (10). 1.0.0 shipped on 18 May 2026 (15). 20+20+18+10+15 = 83.

Kernel 53

Hosted reading. status.kernel.sh on incident.io with a public incident feed (20). In the 90 days from 8 August it lists browser connection failures on 10 September (54 minutes, major), frozen popups on 1 October (71 minutes, major), elevated API errors on 19 October (4 minutes, critical), proxy failures on 23 October (65 minutes, major) and browser creation errors on 4 November (29 minutes, major), plus minor ones. Several majors, two of them an hour or more (0). Rate limits are per organisation with headers on every response, and concurrency is published per plan, but the create-rate numbers aren't (8). 429 with Retry-After, SDK retries with a typed error, safe retry with the same MPP credential and 409 on concurrent pool changes (15). The terms mention service levels in an order form but no public SLA was found (0). The API and MCP server carry no beta label (10). 20 + 0 + 8 + 15 + 0 + 10 = 53.

Chrome DevTools MCP 82

Apache-2.0 (30). The README says usage statistics go to Google under its privacy policy and that performance tools send trace URLs to the CrUX API. No retention figures for either (20). No deprecation policy. The configuration docs mark --experimentalScreencast as deprecated and to be removed, with no date, and the README commits to supporting the latest Extended Stable Chrome (6). Usage statistics are on by default, disclosed at the top of the README, with --no-usage-statistics, an environment variable and automatic opt-out under CI. CrUX lookups switch off with --no-performance-crux (20).

Kernel 61

The platform is closed under a published master services agreement; the MCP server is MIT (20). The privacy policy names Stripe and Google Analytics and an advertising cookie, and states retention as long as needed, with replay retention per plan and zero data retention on Enterprise (18). Deprecated MCP inputs stay as aliases and the changelog notes removals, but no deprecation policy (10). No sub-processor list found; compliance reports sit behind the trust centre (10). 20 + 18 + 10 + 10 = 58.

Chrome DevTools MCP 63

No credentials to leak and nothing to scope, so the middle band (20). --javascript-evaluation false disables script tools and javascript:, data: and vbscript: URLs, --allowed-url-pattern and --blocked-url-pattern restrict the browser (now enforced across redirects), MCP roots confine file access, and --isolated uses a throwaway profile. 1.11.0 on 15 October released the --file-navigations flag that rejects file: URLs. No confirmation step for writes, and --isolated, header redaction and the file-navigation block are all off by default (14). SECURITY.md says page content comes back as-is and tells users to prefer trusted content or have the client guard against prompt injection, and since 1.11.0 also says the server trusts its working directory, environment and npm configuration, so it shouldn't be started in an untrusted workspace (8). A --log-file debug log only, no per-call audit (3). Reports go through Google's open-source vulnerability reward programme, and the two moderate advisories of 2026 (CVE-2026-53765 and CVE-2026-53766, both fixed in 1.1.0) are still the only ones in OSV for the package on 1 November. 1.12.0 also fixes filesystem paths that parse as http or ws URLs escaping path validation, with no advisory (18).

Kernel 81

Scoped API keys with resource and action policies, project scoping and expiry, and OAuth 2.1 for MCP with project-limited tokens (30). Least privilege through scoped keys, a payment cap for cards through the MCP server and vault writes that need their own action (16). Pages an agent browses are untrusted, and we found no prompt-injection guidance in the docs read (4). Audit log search and export on Start-Up and above (13). SOC 2 Type II, HIPAA, PCI DSS and ISO 27001 on the security page and a HackerOne bounty (18). 30 + 16 + 4 + 13 + 18 = 81, before the deduction for the November 2026 incident.

Chrome DevTools MCP 73

59 tools in the full reference across 11 categories. 1.11.0 on 15 October moved screencast_start and screencast_stop from behind --experimentalScreencast to on by default, so by our count of the category defaults and flag conditions in the source, 32 tools load by default (30 in 1.10.1), unchanged in 1.12.0 on 22 October. Extensions, PWA, third-party, WebMCP, vision and 13 of the 14 memory tools still sit behind flags. More than 30 tools (5, was 15 at about 30). Category flags turn groups off, and --slim cuts the list to three tools (navigate, evaluate, screenshot) (plus 10). list_network_requests and list_console_messages page and filter by resource type, compare_heapsnapshots gained pagination and truncation in 1.11.0, the heap snapshot tools paginate by default since 1.12.0, and large outputs can go to a file path instead of inline (20). Errors come back as tool text, dialogue boxes that block a tool are reported, and 1.11.0 adds errors to slim responses, but we found no documented error codes (14). Every tool sets readOnlyHint (28 true, 39 false in the 1.12.0 source), with no destructiveHint (14). Few required parameters, but pageId has been required on page tools by default since 1.8.0. npm only (10).

Kernel 84

Graded mainly on the API, with the MCP server noted. Responses are scoped per resource and the MCP server groups actions into about 32 tools (18). List endpoints page with limit and offset and filter by status (18). Typed SDK errors and documented 409 on concurrent changes, 204 on a pool timeout and 429 (17). Retrying an MPP purchase with the same credential returns the same browser, and the MCP tools carry readOnlyHint where read-only (16). SDKs in TypeScript, Python and Go plus a CLI, with defaults such as a 60-second timeout (15). 18 + 18 + 17 + 16 + 15 = 84.

Chrome DevTools MCP 87

Every tool has a Zod input schema with types, required fields and enums (25). Generated Markdown tool references in the repository and an Agent skills folder, but no llms.txt (7). Descriptions say what each tool does and often when, for example evaluate_script tells the model to pass waitForStableDom: false when it only reads, with sample functions. Few say when not to use a tool (16). Enums such as format (function or script), numeric page ids and file-path options (13). Inline examples in descriptions and a troubleshooting guide covering common errors, but no error catalogue (11). CHANGELOG.md for every release since 0.x (15).

Kernel 93

OpenAPI at kernel.sh/openapi.json and per-endpoint Markdown reference (25). llms.txt with 423 entries and a Markdown twin for each page (10). Endpoint descriptions say when to use alternatives ("For interactive browsing, use GET /audit-logs", pools for bursty traffic) (17). Typed parameters with enums and limits such as memory sizes and timeout maximums (13). Code samples in TypeScript, Python and Go, and documented status codes such as 409 and 204 on pool acquire (13). A dated public changelog and SDK changelogs (15). 25 + 10 + 17 + 13 + 13 + 15 = 93.

Chrome DevTools MCP 60

Free, self-hosted, nothing to buy, so 20 + 20 + 20. No payment protocol (0).

Kernel 65

MPP on POST /mpp/browsers, a 402 challenge paid with a Stripe shared payment token through Link, covering one browser product only, not the API or MCP server (20). Per-second prices public without a login (20). The Developer plan is free with $5 of monthly credit, but whether signup needs a card wasn't stated on the pages read (10). Through MPP an agent gets a browser with no account or key, though a person approves each Link payment (15). 20 + 20 + 10 + 15 = 65.