MCP Server Ecosystem Reference 2026

First Published: 2026-05-16
Last Updated: 2026-05-16

* The contents of this article reflect the state as of the Last Updated date shown above. The MCP ecosystem moves quickly; rows are revised in place as servers ship, are archived, or change transports.

The Model Context Protocol (MCP) crossed the boundary from "interesting open standard" to "default integration layer for agent runtimes" during 2025 and 2026. As of 2026, every major LLM host - Claude Desktop, Claude Code, Cursor, Codex CLI, the ChatGPT desktop app, the OpenAI Agents SDK, and Amazon Bedrock AgentCore Gateway - speaks MCP natively, and the catalog of public MCP servers has grown from a single GitHub README into a tiered ecosystem of reference implementations, vendor-operated remote servers, and a long tail of community packages.

This article is a Reference Aggregation Page that answers two operational questions in one place: "what MCP servers actually exist as of 2026?" and "which transports and authentication modes do they support?" It is refreshed in place as needed within the publication year; each row is a self-contained pointer to its upstream source of truth rather than a usage tutorial. For the deeper end-to-end pattern of building and shipping an MCP server on AWS Lambda, see the companion article MCP Server on AWS Lambda Complete Guide. For the runtimes that consume these servers in production, see Amazon Bedrock AgentCore Implementation Guide Part 1: Runtime, Memory, and Code Interpreter Patterns and Amazon Bedrock AgentCore Implementation Guide Part 4: Multi-Agent Orchestration. For the host side, see Claude Code Getting Started Guide and Claude Code Harness and Environment Engineering Guide.

This snapshot is refreshed as needed within the publication year. Last reviewed: 2026-05. Any value in a row that depends on upstream vendor pages can drift between refreshes; entries flagged with a footnote directly beneath the relevant table are the ones whose upstream is most likely to have changed since this revision was compiled.

1. How This Reference Was Compiled

A snapshot is only useful if the reader can audit how it was built. This section documents the upstream sources, the inclusion bar, the refresh cadence, and what this article deliberately does not cover.

1.1 Sources of Truth

Three classes of upstream were treated as authoritative. Anything else - blog roundups, awesome-lists, social posts - was treated as derivative and not used as a primary source.

Protocol: modelcontextprotocol.io/specification for the current revision (2025-11-25, the first-anniversary release) and the dated revision pages for historical context (2024-11-05, 2025-03-26, 2025-06-18).
Reference servers: the modelcontextprotocol/servers GitHub repository for what counts as a reference implementation, including the archive notices and pointers to maintained forks.
Vendor-operated servers: each vendor's own product page or repository - AWS (awslabs.github.io/mcp), Anthropic (docs.claude.com/en/docs/agents-and-tools/mcp), GitHub (github/github-mcp-server), Cloudflare, Stripe, Atlassian, Notion, Linear, Asana, Sentry, Microsoft (Azure MCP), Vercel, Supabase, and others - as the source of truth for transports, license, authentication, and supported spec revision.

For community servers a single canonical repository was used; abandoned forks and republished mirrors were ignored.

1.2 Inclusion Criteria

A server was included in this reference if at least one of the following held:

It is one of the reference implementations under modelcontextprotocol/servers (active or archived).
It is operated or maintained by a recognized vendor whose primary product the MCP server exposes (the list in §1.1).
It is a community-maintained server with sustained activity in 2026 (commits within the last 90 days), at least one transport that matches the 2025-03-26, 2025-06-18, or 2025-11-25 spec, and clear practical coverage of a category that is not already represented by a reference or vendor entry.

This is deliberately not a complete index of every public MCP server. The long tail of single-purpose community packages is intentionally omitted so the page stays useful as a reference instead of decaying into a directory listing. When a category contains more than a few credible community servers, the most actively maintained one was chosen and the rest are linked from its repository's README, not duplicated here.

1.3 Refresh Cadence

This article is refreshed in place as needed within the publication year. The URL slug is stable - mcp_server_ecosystem_reference_2026 - but the content evolves. Sections most prone to drift are concentrated in two places to make diffs against the prior refresh easy to read:

Recent Additions (§7) - servers that became generally available, joined the reference set, or moved from preview to stable in the last 90 days.
Recent Deprecations (§8) - servers archived, marked end-of-life, or absorbed into a successor since the last refresh.

Refreshes within the publication year overwrite this page in place. The first review of this 2026 edition was completed on 2026-05; subsequent refreshes carry the same URL.

1.4 What This Reference Is Not

Three things are deliberately out of scope to keep this page tractable:

Not a performance benchmark. Tool-call latency, cold start figures, JSON-RPC framing overhead, and Streamable HTTP throughput belong in a separate dedicated benchmark article.
Not a per-server usage guide. Each server has at most one official docs link in its row. Setup instructions, CLI commands, and config snippets are intentionally not duplicated here - the upstream README is authoritative and any duplication here would rot between refreshes.
Not a pricing comparison. Vendor-operated remote MCP servers may have free and paid tiers, but pricing is published on vendor pricing pages and changes more often than this snapshot refreshes.

2. MCP Protocol Quick Reference

Before reading the catalog tables, a short refresher on the protocol shape is useful. MCP is JSON-RPC 2.0 over a configurable transport, with a small set of primitives that hosts and servers negotiate at connect time. This section is a Quick Reference; for the end-to-end mechanics of building a server against the current spec, see the companion article MCP Server on AWS Lambda Complete Guide, and the companion MCP Server Implementation Reference for a vendor-by-vendor comparison pinned to 2025-11-25.

2.1 Spec Revisions Timeline

Four spec revisions are relevant in 2026. The current revision is 2025-11-25, the first-anniversary release. Most production servers still target 2025-06-18 or 2025-03-26 while migrations to 2025-11-25 roll out; hosts negotiate downward gracefully but reject the original pre-2025-03-26 transports for new connections.
* You can sort the table by clicking on the column name.

Revision	Released	Key Additions
2024-11-05	2024-11-05	Initial public spec. JSON-RPC 2.0 base; HTTP+SSE transport; `tools/list`, `resources/list`, `prompts/list` primitives.
2025-03-26	2025-03-26	Streamable HTTP transport (supersedes HTTP+SSE); tool annotations including `readOnlyHint` and `destructiveHint`; resource subscriptions.
2025-06-18	2025-06-18	OAuth 2.1 hardening: RFC 9728 Protected Resource Metadata; RFC 8707 audience binding (Resource Indicators); elicitation primitive; structured tool output schemas and resource links in tool results; `MCP-Protocol-Version` header required on subsequent HTTP requests; JSON-RPC batching support removed.
2025-11-25	2025-11-25	First-anniversary release and current spec. Schema split into a dedicated `schema.ts` per revision under the `modelcontextprotocol/specification` repository; documentation reorganized at `modelcontextprotocol.io/specification/2025-11-25/`. Hosts and servers continue to negotiate the wire version via the `MCP-Protocol-Version` header; servers that do not understand a client's requested version must return HTTP 400.

2.2 Primitives

MCP exposes three core primitives plus four optional capabilities that hosts can advertise to participating servers.

Core primitives
- Tools - functions the model can invoke (tools/list, tools/call).
- Resources - read-only data the host can fetch or subscribe to (resources/list, resources/read, resources/subscribe).
- Prompts - reusable, server-provided prompt templates (prompts/list, prompts/get).
Optional capabilities
- Sampling - the server asks the host to run a model completion on its behalf.
- Roots - the host advertises trusted filesystem roots and notifies the server of changes.
- Elicitation - the server requests user-side structured input (introduced in 2025-06-18).
- Logging - the server emits structured log notifications that surface in the host's UI.

The majority of community servers implement Tools only. Reference and vendor servers increasingly implement Tools + Resources, with Prompts and the optional capabilities still uncommon.

2.3 Transports

Three transports are recognized as of 2026, with one (WebSocket) still outside the core spec.

stdio - the host launches the server as a subprocess and exchanges JSON-RPC frames over its standard streams. The default for local servers in Claude Desktop, Claude Code, and Cursor.
Streamable HTTP - a single HTTPS endpoint accepts POST for JSON-RPC requests and GET for an optional Server-Sent Events stream. The default for remote and multi-tenant servers as of 2025-03-26; it replaced the older HTTP+SSE transport. An Mcp-Session-Id response header lets the server opt into stateful sessions; stateless servers (the recommended default on AWS Lambda) simply omit it.
WebSocket - bidirectional frames. Not yet covered by the official spec but used by a small number of community servers for long-lived agent sessions. Marked [Preview] throughout this reference.

MCP Transport Comparison As of 2026: MCP Host connects to a Local MCP Server via stdio (process trust), to a Remote MCP Server via Streamable HTTP over HTTPS with OAuth 2.1, and to a Streaming MCP Server via WebSocket (experimental) over wss with bearer or OAuth authentication — MCP Transport Comparison As of 2026

2.4 OAuth 2.1 and Protected Resource Metadata

Remote MCP servers in 2026 are expected to publish RFC 9728 Protected Resource Metadata at a discoverable URL and to enforce RFC 8707 audience binding so that an access token issued for one MCP server cannot be replayed at another. Servers that comply fully are flagged Auth: OAuth 2.1 in the catalog tables. Older servers that authenticate with a long-lived bearer token are flagged Auth: API Key. Locally launched stdio servers that rely on the host's process trust are flagged Auth: None (local). AWS-native servers that authenticate via the caller's IAM identity (SigV4) are flagged Auth: IAM SigV4.
The Cloudflare-hosted "remote MCP" pattern - Workers-backed servers exposed through a public OAuth-protected endpoint - has become the de facto reference for vendor-operated multi-tenant servers in 2026, with Stripe, Linear, Asana, and Sentry all converging on a similar shape.

3. Reference Servers by Category

The catalog is organized into four buckets - reference (§4), vendor-operated (§5), community (§6), and refresh-over-refresh delta (§7 and §8). Every table in those sections shares the same column layout, defined in §3.2.

3.1 Index

Jump to a bucket:

§4 Official Reference Implementations
§5 Vendor-Operated Servers - AWS, Anthropic and First-Party, GitHub / Cloudflare / Stripe, Atlassian / Notion / Linear / Asana / Sentry, Microsoft / Google, Supabase / Vercel and other infra
§6 Community Servers by Category - Developer Tools, Search and Knowledge, Database and Data, Observability, Productivity and Communication
§7 Recent Additions
§8 Recent Deprecations
§9 Frequently Asked Questions
§10 References

3.2 Reading the Tables

Every catalog table in this reference uses the same eight columns.

Column	Meaning
Server	Server name, linked to the source of truth (upstream repo or vendor docs).
Maintainer	The org or individual that operates the server and accepts issues.
Language	Primary implementation language.
License	SPDX-style license identifier or `Proprietary` for vendor-only services.
Transports	`stdio` / `Streamable HTTP` / `stdio+HTTP` / `WebSocket`.
Auth	`None (local)` / `None (public)` / `OAuth 2.1` / `API Key` / `IAM SigV4` / `DB credentials` / `kubeconfig` (definitions below).
Status	Stability badge (legend below).
Spec Rev	MCP spec revision the server targets.

Status badge legend:

[Stable] - production-grade. No breaking changes in the last 90 days; vendor or maintainer commits to a deprecation window.
[Beta] - feature-complete but evolving. Expect minor breaking changes between releases.
[Preview] - early access. May not implement all primitives or all transports.
[Deprecating YYYY] or [Deprecating YYYY-MM] - announced end-of-life. The month is included when the vendor has published a specific cut-off date; year-only is used when only the year is publicly announced. Successor (if any) is noted in §8.

Auth value legend:

None (local) - the server runs as a stdio subprocess and inherits the host user's privileges; no transport-level authentication.
None (public) - a Streamable HTTP server intentionally exposed without authentication because it serves only public read-only data (e.g. aws-knowledge-mcp-server).
OAuth 2.1 - RFC 9728 Protected Resource Metadata published, RFC 8707 audience binding enforced. See §2.4.
API Key - a long-lived bearer token (vendor-issued or user-issued) passed as an HTTP header or environment variable.
IAM SigV4 - the caller's AWS credentials sign each request; permissions are governed by the caller's IAM identity rather than by the server.
DB credentials - a database connection string (username/password or a DSN) is supplied at server start time; the MCP server itself is unauthenticated and trusts whoever can reach it on stdio.
kubeconfig - the server reads a local kubeconfig file at start time and inherits its cluster credentials; no MCP-level authentication.

Cells whose upstream value the author could not verify against vendor docs at the time of this snapshot are flagged with a footnote directly beneath the table. These are the ones to double-check before depending on the value in production.

3.3 Category Buckets

The catalog uses twelve practical categories. Each category appears in exactly one of §4 (reference), §5 (vendor-operated), or §6 (community), depending on where the most authoritative current implementation lives - so the same product domain (e.g. Database) shows up under aurora-postgres-mcp-server in §5.1 and under postgres-mcp in §6.3 without being split across both.

Filesystem and Local IO — covered in §4 (reference filesystem).
Web / Fetch / Browser — covered in §4 (reference fetch) and §6.1 (playwright-mcp).
Database — covered in §5.1 (AWS Labs Aurora / DynamoDB) and §6.3 (Postgres, MongoDB, ClickHouse, Redis, Elasticsearch, Snowflake).
Search and Knowledge — covered in §5.1 (aws-knowledge-mcp-server) and §6.2 (Exa, Tavily, Perplexity, Brave).
Developer Tools (Git, CI, Build, Containers, Kubernetes, Terraform) — covered in §4 (reference git), §5.3 (GitHub) and §6.1 (Playwright, Kubernetes, Docker, Terraform, shell, Jupyter).
Productivity (Calendar, Mail, Docs, Notes) — covered in §5.4 (Notion) and §6.5 (Todoist, Gmail, Google Calendar).
Communication (Chat, Notification) — covered in §6.5 (Slack, Discord).
AWS-native — covered in §5.1.
GCP-native — covered in §5.5 (community google_workspace_mcp after Google's first-party repos were archived).
Azure-native — covered in §5.5 (consolidated microsoft/mcp catalog).
Observability and Security — covered in §5.4 (Sentry) and §6.4 (Grafana, Loki, Prometheus).
Payments and Commerce — covered in §5.3 (Stripe).

MCP Server Ecosystem Map As of 2026: MCP Spec 2025-06-18 anchors the buckets of Reference implementations (sec 4), AWS Labs servers (sec 5.1), Anthropic and partner connectors (sec 5.2-5.4), Hyperscaler vendor servers (sec 5.5: Microsoft / Google), Infrastructure platforms (sec 5.6: Supabase / Vercel), and Community-maintained servers (sec 6) — MCP Server Ecosystem Map As of 2026

4. Official Reference Implementations

The modelcontextprotocol/servers repository is the canonical answer to "what should an MCP server look like?" As of 2026 most of the original first-party reference servers were archived during 2025 and migrated to vendor or community ownership, leaving a smaller curated set in the upstream repo plus explicit pointers to maintained forks. The archived rows live in §8 Recent Deprecations together with their successor links.
* You can sort the table by clicking on the column name.

Server	Maintainer	Language	License	Transports	Auth	Status	Spec Rev
filesystem	MCP Project	TypeScript	MIT	stdio	None (local)	[Stable]	2025-06-18
fetch	MCP Project	Python	MIT	stdio	None (local)	[Stable]	2025-06-18
git	MCP Project	Python	MIT	stdio	None (local)	[Stable]	2025-06-18
memory	MCP Project	TypeScript	MIT	stdio	None (local)	[Stable]	2025-06-18
time	MCP Project	Python	MIT	stdio	None (local)	[Stable]	2025-06-18
sequentialthinking	MCP Project	TypeScript	MIT	stdio	None (local)	[Stable]	2025-06-18
everything	MCP Project	TypeScript	MIT	stdio+HTTP	None (local)	[Stable]	2025-06-18

The everything server is intentionally not for production use - it is a test server that exercises every primitive and capability the spec defines, used by host implementers to validate their client. The memory server provides a minimal in-memory key/value store and a knowledge-graph variant; production agents that need persistence usually pair MCP with a host-managed store (Bedrock AgentCore Memory, OpenAI Memory) instead of relying on this reference implementation.

5. Vendor-Operated Servers

This is the section that has grown the fastest between 2025 and 2026. Vendor-operated servers - servers that the product vendor itself runs (or publishes as a first-party install) - have a noticeably different operational shape from the reference set: most are Streamable HTTP, most use OAuth 2.1, and most map one-to-one onto an existing product's API surface.

5.1 AWS

AWS Labs publishes a coordinated catalog of MCP servers at awslabs.github.io/mcp. The list below is the most operationally relevant subset as of 2026; the upstream catalog page is authoritative for the complete inventory. All AWS Labs servers can run as stdio local servers and most also expose a Streamable HTTP variant suitable for hosting in AWS Lambda (see MCP Server on AWS Lambda Complete Guide) or as an AgentCore Gateway target.
* You can sort the table by clicking on the column name.

Server	Maintainer	Language	License	Transports	Auth	Status	Spec Rev
aws-api-mcp-server	AWS Labs	Python	Apache-2.0	stdio+HTTP	IAM SigV4	[Stable]	2025-06-18
aws-knowledge-mcp-server	AWS Labs	Python	Apache-2.0	Streamable HTTP	None (public)	[Stable]	2025-06-18
cost-analysis-mcp-server	AWS Labs	Python	Apache-2.0	stdio+HTTP	IAM SigV4	[Stable]	2025-06-18
cdk-mcp-server	AWS Labs	Python	Apache-2.0	stdio	IAM SigV4	[Stable]	2025-06-18
cloudformation-mcp-server	AWS Labs	Python	Apache-2.0	stdio+HTTP	IAM SigV4	[Stable]	2025-06-18
eks-mcp-server	AWS Labs	Python	Apache-2.0	stdio	IAM SigV4	[Stable]	2025-06-18
lambda-tool-mcp-server	AWS Labs	Python	Apache-2.0	stdio+HTTP	IAM SigV4	[Stable]	2025-06-18
bedrock-kb-retrieval-mcp-server	AWS Labs	Python	Apache-2.0	stdio+HTTP	IAM SigV4	[Stable]	2025-06-18
aurora-postgres-mcp-server	AWS Labs	Python	Apache-2.0	stdio	IAM SigV4	[Stable]	2025-06-18
dynamodb-mcp-server	AWS Labs	Python	Apache-2.0	stdio	IAM SigV4	[Stable]	2025-06-18
Amazon Bedrock AgentCore Gateway	AWS	(managed)	Proprietary	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18

AgentCore Gateway is a special case. It is not itself a server in the sense of a Tools provider - it is a translation layer that fans existing MCP servers (or REST APIs, Lambda functions, Smithy models, OpenAPI specs) out to any number of agents over a single Streamable HTTP endpoint with OAuth 2.1 authorization on the front and IAM-scoped access on the back. The Gateway pattern is the recommended way to expose internal AWS workloads to AgentCore Runtime agents, and is covered end-to-end in AgentCore Implementation Guide Part 4.

5.2 Anthropic and First-Party Integrations

Anthropic's role in the ecosystem is twofold: they author the spec, and they ship a set of first-party connectors that Claude Desktop's "Connectors" UI installs with one click. The list below is the catalog state as of 2026; Claude Desktop's settings UI is authoritative for the current shipping set.
* You can sort the table by clicking on the column name.

Server	Maintainer	Language	License	Transports	Auth	Status	Spec Rev
Claude Desktop bundled MCP servers	Anthropic	(various)	(various)	stdio	None (local)	[Stable]	2025-06-18
Claude Desktop Custom Connectors (OAuth)	Anthropic	(host feature)	Proprietary	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18
Anthropic Messages API MCP support	Anthropic	(API feature)	Proprietary	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18

The Messages API MCP feature lets a client call an external Streamable HTTP MCP server inline with a Messages request, with Anthropic acting as the MCP client on behalf of the application. This is the canonical way to add MCP-mediated tools to a Claude API integration without running an in-process MCP client.

5.3 GitHub / Cloudflare / Stripe

Three platforms whose MCP servers are the most cited examples of "remote OAuth-protected MCP done right" in 2026.
* You can sort the table by clicking on the column name.

Server	Maintainer	Language	License	Transports	Auth	Status	Spec Rev
GitHub MCP Server	GitHub	Go	MIT	stdio+HTTP	OAuth 2.1	[Stable]	2025-06-18
Cloudflare MCP Server	Cloudflare	TypeScript	Apache-2.0	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18
Cloudflare Workers Remote MCP	Cloudflare	(framework)	BSD-3-Clause	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18
Stripe Agent Toolkit MCP	Stripe	TypeScript	MIT	stdio+HTTP	API Key	[Stable]	2025-06-18
Stripe Hosted MCP	Stripe	(managed)	Proprietary	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18

The GitHub MCP Server replaced the original community modelcontextprotocol/servers/github reference in late 2025 and is now the canonical way to access repositories, issues, pull requests, Actions, and Code Search from Claude Code, Cursor, and AgentCore. The Cloudflare Workers Remote MCP pattern is a framework rather than a single server - it gives developers a one-file template for shipping their own OAuth-protected MCP server on Workers, and is what powers many of the SaaS-vendor servers listed in §5.4.

5.4 Atlassian / Notion / Linear / Asana / Sentry

The SaaS-vendor cluster. All five converged on the Cloudflare-style remote OAuth pattern during 2025-2026.
* You can sort the table by clicking on the column name.

Server	Maintainer	Language	License	Transports	Auth	Status	Spec Rev
Atlassian Remote MCP Server	Atlassian	(managed)	Proprietary	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18
Notion MCP Server	Notion	(managed)	Proprietary	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18
Linear MCP Server	Linear	(managed)	Proprietary	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18
Asana MCP Server	Asana	(managed)	Proprietary	Streamable HTTP	OAuth 2.1	[Beta]	2025-06-18
Sentry MCP Server	Sentry	TypeScript	FSL-1.1-Apache-2.0	stdio+HTTP	OAuth 2.1	[Stable]	2025-06-18

What makes this cluster useful as a reference is its uniformity. All five vendors converged on the same shape - Streamable HTTP transport, OAuth 2.1 with audience binding, managed hosting on either Cloudflare Workers or an equivalent edge runtime, and a one-click install path in Claude Desktop's Custom Connectors UI. If you are designing an MCP server for a SaaS product in 2026, this cluster is the canonical reference architecture to copy from before deviating.

5.5 Microsoft / Google

The two hyperscalers that are not AWS. Microsoft consolidated its servers into a single broad catalog repository during 2025-2026 (the earlier Azure/azure-mcp repository was archived in 2026-02 and migrated into microsoft/mcp under Azure.Mcp.Server; see §8). Google does not currently publish a first-party Workspace MCP server - Google's own googleworkspace/dev-assist and googleworkspace/developer-mcp repositories were archived in late 2025, so the community-maintained taylorwilsdon/google_workspace_mcp is the canonical entry that covers Drive, Calendar, Gmail, Docs, Sheets, Slides, Chat, Forms, Tasks, and Search behind a single OAuth flow.
* You can sort the table by clicking on the column name.

Server	Maintainer	Language	License	Transports	Auth	Status	Spec Rev
Microsoft MCP catalog	Microsoft	(various)	MIT	stdio+HTTP	OAuth 2.1	[Stable]	2025-06-18
Microsoft Dev Box MCP (@microsoft/devbox-mcp)	Microsoft	TypeScript	MIT	stdio	OAuth 2.1	[Beta]	2025-06-18
Google Workspace MCP (community)	Community (taylorwilsdon)	Python	MIT	stdio+HTTP	OAuth 2.1	[Beta]	2025-06-18

The community google_workspace_mcp package exposes Google's product-specific surfaces (Drive, Calendar, Gmail, Docs, Sheets, Slides, Chat, Forms, Tasks, Search) behind a single OAuth flow rather than as separate one-product servers. The canonical non-Anthropic, non-AWS MCP host on the Google side - Gemini CLI - is excluded from this server catalog because it consumes MCP servers rather than exposing tools; treat it as a Google-side analog to Claude Code and Cursor.

5.6 Supabase / Vercel and Other Infrastructure

Application infrastructure vendors that ship MCP servers for their own developer surfaces.
* You can sort the table by clicking on the column name.

Server	Maintainer	Language	License	Transports	Auth	Status	Spec Rev
Supabase MCP Server	Supabase	TypeScript	Apache-2.0	stdio+HTTP	API Key	[Stable]	2025-06-18
Vercel MCP Server	Vercel	(managed)	Proprietary	Streamable HTTP	OAuth 2.1	[Stable]	2025-06-18
Neon MCP Server	Neon	TypeScript	Apache-2.0	stdio+HTTP	API Key	[Stable]	2025-06-18
Upstash MCP Server	Upstash	TypeScript	Apache-2.0	stdio+HTTP	API Key	[Stable]	2025-06-18
PostHog MCP Server	PostHog	TypeScript	MIT	stdio+HTTP	API Key	[Beta]	2025-06-18

The split between API-Key and OAuth 2.1 in this cluster tracks the underlying product surface. Vendors whose primary surface is already a developer-issued API key (Supabase, Neon, Upstash, PostHog) ship MCP servers that reuse the same key. Vendors whose surface is account-scoped end-user data (Vercel deployments tied to a Vercel account) layer OAuth 2.1 on top. Pick the auth mode that matches the underlying product rather than treating it as a free-floating MCP design choice.

6. Community Servers by Category

Community servers fill the gaps the reference and vendor sets leave open. The selection below is the actively maintained, category-representative top of each bucket as of 2026; the long tail (single-use forks, archived projects, hobbyist experiments) is intentionally not included.