Both paths are documented. Usually OAuth for a hosted server and a key for the self hosted or legacy endpoint. The bucket is a keyword match over the mcp_auth field, run at build time, and the verbatim field ships in the row beside it so you can check the parse yourself. Where the two disagree, the verbatim field is the fact and the bucket is the convenience.
| Tool | MCP status | Server URL | mcp_auth, verbatim | Gate |
|---|---|---|---|---|
| Airbyte airbyte.com | Official MCP | https://docs.airbyte.com/ai-agents/interfaces/mcp | Two-layer OAuth 2.0 - OAuth into the Airbyte account/org for the MCP server itself, plus separate OAuth or API-key auth per connected third-party... | Free to start |
| Anymail Finder anymailfinder.com | Official MCP | https://api.anymailfinder.com/mcp +1 more | Browser-based OAuth-style sign-in and approval for Claude, ChatGPT and Cursor, with an API key fallback for clients that cannot do browser sign-in. | Free to start |
| Apideck apideck.com | Official MCP | https://github.com/apideck-libraries/mcp +1 more | Managed OAuth via Apideck Vault on the hosted endpoint, or x-apideck-api-key plus x-apideck-app-id plus x-apideck-consumer-id headers for direct use. | Free to start |
| Cal.com cal.com | Official MCP | https://github.com/calcom/cal-mcp +1 more | Two paths. Hosted server (mcp.cal.com) uses OAuth 2.1 - "your client handles the authorization flow automatically," no API key needed.... | Free to start |
| Calendly calendly.com | Official MCP | https://developer.calendly.com/calendly-mcp-server +3 more | OAuth 2.1 Authorization Code + PKCE (S256) with Dynamic Client Registration (RFC 7591). Personal access tokens are not supported. Fully hosted by... | Free to start |
| Composio composio.dev | Official MCP | https://docs.composio.dev/mcp/overview | Composio brokers OAuth for each connected toolkit (HubSpot, Gmail, Slack, etc.) on the user's behalf, then gates the MCP endpoint itself with an... | Free to start |
| Fireflies.ai fireflies.ai | Official MCP | https://guide.fireflies.ai/articles/8272956938-learn... +1 more | OAuth (Google/Microsoft, recommended) or manual API key for Claude Desktop and other MCP clients. | Free to start |
| LeadMagic leadmagic.io | Official MCP | https://github.com/LeadMagic/leadmagic-mcp +1 more | api key for local/self-hosted install (LEADMAGIC_API_KEY env var); OAuth Bearer token (Clerk-issued) for the hosted remote MCP - hosted version does... | Free to start |
| MeetGeek meetgeek.ai | Official MCP | https://mcp.meetgeek.ai/mcp +2 more | Two paths. The cloud server uses OAuth 2.0 with Google or Microsoft sign-in and no API key. The self-hosted server runs locally on Node.js and... | Free to start |
| Prospeo prospeo.io | Official MCP | https://github.com/prospeo-v2/prospeo-mcp-server | OAuth 2.0 for the hosted server (auto-handled by Claude.ai/Desktop via the MCP directory); local/self-hosted setup uses an API key via... | Free to start |
| Tavus tavus.io | Official MCP | https://mcp.tavus.io/mcp +3 more | OAuth 2.0 browser-based flow; the exchange mints a per-user API key server-side, nothing stored in client config. | Free to start |
| Warmly warmly.ai | Official MCP | https://www.warmly.ai/launches/warmly-mcp-and-api-ar... | OAuth for the MCP connector; API key for the REST API | Free to start |
| Warmly (Warmly.ai) warmly.ai | Official MCP | https://www.warmly.ai/launches/warmly-mcp-and-api-ar... | MCP uses OAuth-based login (no manual key management); the separate REST API (opps-api.getwarmly.com) uses a per-organization API key. | Free to start |
| Zapier zapier.com | Official MCP | https://zapier.com/mcp +1 more | Reuses Zapier's existing 13+ year credential infrastructure - connect an AI client (Claude, ChatGPT, Cursor) through a guided ~5-minute flow that... | Free to start |
| Affinity affinity.co | Official MCP | https://mcp.affinity.co/mcp +1 more | OAuth where the client supports it, otherwise an API key. Local deployment is API key only. All MCP queries inherit the connecting user's existing... | Paid, self-serve |
| Chili Piper chilipiper.com | Official MCP | https://www.chilipiper.com/products/mcp +3 more | Two supported paths, both vendor-documented. Option A (vendor-recommended): a Chili Piper Edge API key, generated by an admin in Command Center and... | Paid, self-serve |
| Chili Piper chilipiper.com | Official MCP | https://www.chilipiper.com/products/mcp +3 more | Two supported paths, both vendor-documented. Option A (vendor-recommended): a Chili Piper Edge API key, generated by an admin in Command Center and... | Paid, self-serve |
| Close (Close CRM) close.com | Official MCP | https://help.close.com/docs/mcp-server +1 more | Dual - OAuth 2.0 with Dynamic Client Registration (recommended; used by Claude, ChatGPT, Cursor) or API-key auth via custom headers (Close-API-Key,... | Paid, self-serve |
| Dropcontact dropcontact.com | Official MCP | https://www.dropcontact.com/mcp-dropcontact | Hosted server at mcp.dropcontact.com/mcp/, supporting OAuth (recommended, browser-based) or a Dropcontact API token/key passed via headers; also... | Paid, self-serve |
| Fiber AI fiber.ai | Official MCP | https://mcp.fiber.ai/mcp/v3 +2 more | OAuth via Clerk on the v3 endpoint; x-api-key header on the v2 and legacy endpoints. | Paid, self-serve |
| HeyReach heyreach.io | Official MCP | https://www.heyreach.io/mcp +1 more | workspace-scoped "MCP key" + connection URL (API-key-style, not OAuth) | Paid, self-serve |
| Intercom (Fin) intercom.com | Official MCP | https://mcp.intercom.com/mcp +2 more | OAuth (browser-based, recommended) or a Bearer token using an Intercom API token; Streamable HTTP transport, 13 exposed tools covering conversations,... | Paid, self-serve |
| lemlist lemlist.com | Official MCP | https://developer.lemlist.com/mcp/setup +1 more | OAuth (browser-based PKCE flow, recommended) or API key via X-API-Key header | Paid, self-serve |
| Make make.com | Official MCP | https://developers.make.com/mcp-server | Two supported methods - OAuth via Make's cloud (endpoint mcp.make.com) or an MCP Token generated from the user's Make profile, sent as a Bearer... | Paid, self-serve |
| Metorial metorial.com | Official MCP | https://metorial.com | Fully custodial - Metorial stores and centrally manages OAuth tokens for every connected integration ("no tokens to manage" for the end user), with... | Paid, self-serve |
| Octave octavehq.com | Official MCP | https://docs.octavehq.com/mcp/overview +3 more | Browser OAuth. Per the vendor's Claude Code setup doc you add the server with "claude mcp add octave-myWorkspace --transport http... | Paid, self-serve |
| Pipedream MCP pipedream.com | Official MCP | https://mcp.pipedream.com | OAuth/API-key credentials for each underlying app are stored by Pipedream and isolated per end user; Pipedream states credentials are "never exposed... | Paid, self-serve |
| The Swarm theswarm.com | Official MCP | https://bee.theswarm.com/mcp +1 more | OAuth via personal Swarm login (native Claude and ChatGPT app connectors) or team API key via x-api-key header for any MCP client supporting custom... | Paid, self-serve |
| Waalaxy waalaxy.com | Official MCP | https://docs.waalaxy.com/mcp-server +1 more | user-based OAuth 2.1 via magic-link sign-in; vendor docs explicitly state bearer API keys are NOT supported by the MCP server (differs from the... | Paid, self-serve |
| Wiza wiza.co | Official MCP | https://mcp.wiza.co/mcp +2 more | OAuth 2.1 with PKCE for clients that support it, otherwise a static bearer token in the Authorization header using a Wiza API key. Streamable HTTP... | Paid, self-serve |
| Woodpecker woodpecker.co | Official MCP | https://developers.woodpecker.co/docs/mcp/ +1 more | hosted OAuth-style flow (Claude-specific) or self-hosted Docker setup using a Woodpecker API key | Paid, self-serve |
| Seamless.AI seamless.ai | Official MCP | https://docs.seamless.ai/mcp-docs +1 more | OAuth 2.1 or API key; docs state "MCP access must be enabled on your account" - i.e. gated per-account, contact admin/support to turn on | Enterprise only |
| Seismic seismic.com | Official MCP | https://developer.seismic.com/seismicsoftware/docs/s... | Streamable HTTP transport per Seismic's MCP documentation; the specific credential type (API key vs. OAuth) was not confirmed in the sources reviewed. | Enterprise only |
| Similarweb similarweb.com | Official MCP | https://mcp.similarweb.com +3 more | CONFLICTING VENDOR STATEMENTS, flagged rather than resolved. Both Similarweb developer docs pages state an active Similarweb API key from Account... | Enterprise only |
| Syncari syncari.com | Official MCP | https://syncari.com/mcp-server/ | unknown - the MCP server page describes real-time, entity/field-level access control and audit logging but does not state whether connection auth is... | Enterprise only |
| UserGems usergems.com | Official MCP | https://www.usergems.com/product/mcp | unknown - connects inside Claude/ChatGPT per the product page, but the exact auth mechanism (OAuth vs. API key) isn't disclosed publicly. | Enterprise only |
| Anaplan (PlanIQ / Anaplan Forecaster) anaplan.com | Official MCP | https://www.anaplan.com/platform/intelligence/ | unknown - described only as a "governed MCP connection" with permission/audit controls; the specific credential mechanism (API key vs. OAuth) is not... | Gate unknown |
| Default default.com | Official MCP | https://www.default.com/product/platform | unknown - not specified on the public page (plausibly API key or OAuth given CRM-grade data access, but unconfirmed) | Gate unknown |
| Endgame endgame.io | Official MCP | https://docs.endgame.io/features/mcp-server +1 more | OAuth (browser-based) for individual users via Claude/ChatGPT/Claude Code/Codex connectors; Bearer-token service-account API keys (issued at... | Gate unknown |
| Reclaim.ai reclaim.ai | Official MCP | https://mcp.reclaim.ai | OAuth (official hosted server). A separate unofficial/community server also exists (github.com/universalamateur/reclaim-mcp-server, explicitly marked... | Gate unknown |
| Zoom Revenue Accelerator zoom.com | Official MCP | https://news.zoom.com/zoom-revenue-accelerator-mcp-c... +1 more | OAuth - Zoom user-level OAuth access token (env var ZOOM_REVENUE_ACCELERATOR_MCP_ACCESS_TOKEN), plus an OpenAI Codex plugin variant. | Gate unknown |
| Clari Copilot clari.com | Community MCP | https://www.scalekit.com/connectors/claricopilot +1 more | Scalekit-hosted connector uses per-user delegated OAuth-style authorization in Scalekit's own token vault. The underlying Clari Copilot REST API... | Paid, self-serve |
| UpLead uplead.com | Community MCP | https://zapier.com/mcp/uplead +1 more | Handled through the Zapier/Pipedream platform's own connector auth (API key entered into that third-party platform), not a UpLead-native OAuth or... | Paid, self-serve |
| BombBomb bombbomb.com | Community MCP | https://zapier.com/mcp/bombbombcom | Rides Zapier's own OAuth/API-key connection to BombBomb; not a native BombBomb MCP auth flow. | Enterprise only |
| Jiminny jiminny.com | Community MCP | https://glama.ai/mcp/servers/@fzheng0222/jiminny-mcp +1 more | Community server: JIMINNY_TOKEN API token. Zapier's hosted connector uses Zapier's own OAuth layer. | Gate unknown |
Counted 2026-08-25 from directory.json and reconciled against tools_recount.py. Nothing on this page is hand maintained: it is a filter over the same 293 entries the rest of the site is built from. Ordered by the published rule: official MCP first, then community, then unknown, then n/a, then none-found; within each band gate order is free, paid, enterprise-leaning, enterprise-only, unknown; then alphabetical by name. Computed, never curated, never purchasable.