Browserbase vs Kernel

Browserbase 43

A project API key in the X-BB-API-Key header. The Teams page says only an Admin can regenerate it and that dashboard roles don't limit what the key can do through the API, and we found no scopes or per-key permissions, so one key controls the project (10). The hosted MCP setup page still shows the key in the URL as ?browserbaseApiKey= on 1 November, a secret in a query string (minus 10). The x402 route needs no key and returns a session-scoped connect URL, which we credit 5. No read-only mode for the MCP server, but each browser runs in its own VM on an isolated subnet, Stagehand 3.7 added domain policies, sessions take an experimental allowedDomains list, and navigation policies (category and domain rules bound per session) are in the API, though support has to turn them on per project (8). Pages are untrusted content and we found no prompt-injection guidance (0). Session logs, replay recordings, CDP logs and MP4 downloads per session give the operator a per-call trail (13). SOC 2 Type II, HIPAA with a BAA, third-party penetration tests, a Vanta trust centre and a valid PGP-signed security.txt expiring 2027-06-01, unchanged on 1 November. No bug bounty found (17). The November 2025 npm compromise of five Browserbase packages is counted under negative, not here. 10-10+5+8+0+13+17 = 43.

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.

Browserbase 90

status.browserbase.com runs on incident.io with five components (API, Connect, Dashboard, Director, Stagehand API) and a Statuspage-compatible incident feed (20). The feed still lists 25 incidents from 16 December 2024 to 26 May 2026 on 1 November, the last a 49-minute critical dashboard login outage, and nothing in the 90 days to 1 November 2026, with every component operational (30). Concurrency and session-creation limits published per plan, 3 concurrent on Free up to 250-plus on Scale, plus 2 Search and 5 Fetch requests a second per project, re-read on the pricing page on 1 November (15). 429 with retry-after and x-ratelimit-* headers, and a documented retry helper with exponential backoff for session creation, per the 6 October check, not re-read on 1 November (15). No SLA on the pricing page or in anything else we read (0). The sessions API is GA (10). 20+30+15+15+0+10 = 90.

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.

Browserbase 90

x402 on x402.browserbase.com for browser sessions (create, status, extend, terminate) at $0.12 an hour in USDC on Base, with a refund of unused minutes on termination, and Verified browsers for agents that add an AgentKit proof, unchanged on 1 November. Fetch, Search and the main api.browserbase.com host aren't covered. Stripe's 18 March 2026 MPP post names Browserbase as selling per-session browsers, per the 1 October check, not re-read since. So partial (30). Per-hour and per-1,000-call prices published without login. Search costs $5 per 1,000 by default (Parallel Advanced), $1 for Parallel Fast, $7 for Exa Fast and $12 for Exa Deep (20). Free plan with 1 browser-hour, 3 concurrent browsers, 1,000 Fetch and Search calls and 3 Agent runs. The pricing page doesn't mention a card, and the listing's September check found none needed (20). An agent with a wallet gets a browser with no account (20). 30+20+20+20 = 90.

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.

Browserbase 80

OpenAPI 3.0.0 at docs.browserbase.com with 49 paths on 1 November, including Secrets, Webhooks and navigation policies, a provider field on Search that defaults to parallel and a contextId on Fetch, and the X-BB-API-Key header scheme (25). llms.txt and Markdown twins of the docs (10). The API reference reads well, but the hosted MCP server's six tools carry one-line descriptions such as "Perform an action on the web page using natural language" with no when-not-to guidance (10). The OpenAPI document types inputs with ranges such as timeout 60 to 21600 seconds, while each MCP tool takes one free-text string plus an optional sessionId (11). Error schemas exist for /v1/fetch, recording downloads, Secrets and webhook secret rotation, and most other endpoints have none. Code samples are plentiful (9). /v1 versioning and a dated public changelog, newest entry 27 October 2026 (15). 25+10+10+11+9+15 = 80.

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.

Browserbase 72

The platform is closed with published terms, and Stagehand is MIT (20). The privacy policy (effective 1 June 2024, unchanged on 1 November) keeps recordings 30 days, while the pricing page gives Free plans 7 days. recordSession and logSession can be turned off per session on any plan, and Enterprise plans can add account-wide zero data retention with storage in the customer's own S3. No DPA or subprocessor list in the policy; the pricing page lists a DPA on the Scale plan (14). No deprecation policy. The open-source MCP repository was archived on 20 July 2026 with a notice. The MCP setup page no longer mentions local STDIO on 1 November (5). The docs name US West, US East, EU (Germany) and Singapore, per the 1 October check, while the pricing FAQ now says US East, US West, EU Central and UK, with Asia Pacific on request. Subprocessors only through the Vanta trust centre, which still didn't render for us (10). 20+14+5+10 = 49.

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.

Browserbase 75

The hosted MCP server has six compact tools, and the API lists take limit, so context cost is low. Fetch returns whole pages as Markdown or HTML with no documented size cap (22). Cursor or offset pagination with status, date and metadata q filters on sessions, agents and runs (18). Error bodies are documented for Fetch, downloads and Secrets only (12). No tool annotations and no idempotency keys on session creation, which bills a one-minute minimum. Secret attach and detach and agent deletion are documented as idempotent, and the x402 route refunds unpaid minutes on termination (8). Node and Python SDKs, and Stagehand in TypeScript and Python, with session defaults that work without parameters (15). 22+18+12+8+15 = 75.

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.