There are 764 curated MCP servers in the AgentNDX directory right now. But which ones actually get attention? Not all categories pull equal weight. Some draw steady developer interest. Others sit quietly with strong tooling that nobody thinks to look for.
We looked at the distribution of servers, tags, and capabilities across the directory to map where developer demand concentrates — and where the gaps are.
Where the Servers Are
The directory breaks into 10 categories. The split is not even close to balanced.
| Category | Servers | Share |
|---|---|---|
| Data | 225 | 29.5% |
| Infrastructure | 130 | 17.0% |
| Productivity | 108 | 14.1% |
| Code | 79 | 10.3% |
| AI | 48 | 6.3% |
| Payments | 41 | 5.4% |
| Communication | 37 | 4.8% |
| Media | 37 | 4.8% |
| Web | 36 | 4.7% |
| Identity | 23 | 3.0% |
Data dominates. Nearly a third of all curated servers handle databases, analytics, search, or data pipelines. This matches what we see in developer workflows: AI agents spend most of their time pulling, transforming, and querying structured data.
Infrastructure takes second place at 17%. These are the cloud, DevOps, and deployment servers — the kind developers need once they move past local prototypes and start running agents in production.
What Tags Tell Us About Demand
Tags reveal more granular intent than categories. When a server ships with enterprise, open-source, or analytics as tags, those signal what developers are actually filtering for.
The top 15 tags across the directory:
| Tag | Count |
|---|---|
| enterprise | 134 |
| open-source | 116 |
| security | 59 |
| analytics | 54 |
| compliance | 47 |
| automation | 37 |
| database | 32 |
| governance | 31 |
| marketing | 29 |
| observability | 28 |
| managed | 28 |
| devops | 25 |
| sql | 24 |
| finance | 24 |
| monitoring | 23 |
Two patterns stand out. First, enterprise and open-source are the two most common tags, and they often appear on the same servers. Developers want enterprise-grade tooling they can self-host and inspect. Second, security, compliance, and governance together account for 137 tag appearances. That is not a niche concern — it reflects the real friction organizations face when they hand data access to AI agents.
The analytics and sql tags point to the same story the category data tells: most agent work is data work. Developers are not searching for novelty. They are searching for reliable pipes to their databases.
How Servers Connect
Transport protocol is a practical choice that shapes how developers integrate MCP servers into their stacks.
| Transport | Servers | Share |
|---|---|---|
| stdio | 468 | 61.3% |
| HTTP | 292 | 38.2% |
| SSE | 3 | 0.4% |
stdio still leads by a wide margin. It is the simplest transport to set up — run a local process, pipe JSON, done. For developers building with Claude Desktop or local coding agents, stdio is the path of least resistance.
HTTP is gaining ground. At 38%, it already handles more than a third of all servers. This makes sense: production deployments, hosted services, and multi-user setups all need HTTP. As more teams move agents beyond local dev environments, expect this number to keep climbing.
SSE is essentially dead as a transport option. The shift to HTTP streaming made SSE redundant, and the numbers confirm it.
Authentication Patterns
How servers handle auth says a lot about who they are built for.
| Auth Type | Servers | Share |
|---|---|---|
| API Key | 487 | 63.7% |
| OAuth | 155 | 20.3% |
| None | 119 | 15.6% |
| x402 | 2 | 0.3% |
API keys dominate because they work. They are easy to provision, simple to rotate, and every developer understands them. For most MCP integrations, an API key is all the auth you need.
OAuth at 20% reflects the growing number of servers that connect to platforms with existing user accounts — Slack, GitHub, Google Workspace, Salesforce. These servers need to act on behalf of a user, not just access an API.
The 119 servers with no auth are mostly open-source tools and local utilities. They run on your machine, access your files, and do not need credentials because they inherit your permissions.
x402 payment auth is still early. Only 2 servers use it as their primary auth method. But with 5 servers listing x402 capabilities in some form, the infrastructure is being laid. Agent-to-agent payments will grow as autonomous workflows become more common.
Health and Reliability
Of the 764 curated servers, 682 (89.3%) show active health status. That is a strong number for an ecosystem this young. The remaining 81 servers report unknown health, usually because they run on stdio and do not expose a public endpoint for health checks.
This matters for developers evaluating which server to adopt. An active health status on AgentNDX means the server was reachable and responsive at last check — not that it will stay that way forever, but it is a signal worth filtering on.
What Developers Actually Want
Pull these threads together and a clear picture forms:
Data access is the top job. Nearly 30% of servers, plus dominant tags like analytics, sql, and database, all point to the same need. Developers want their agents to read from and write to structured data stores. If you are building an MCP server and wondering what use case to target, start with data.
Enterprise readiness matters more than you think. The enterprise tag shows up on 134 servers — more than any other tag. Developers are not just experimenting. They are evaluating MCP servers for production use inside organizations with security, compliance, and governance requirements.
Local-first is still the default. stdio at 61% and API key auth at 64% tell the same story: most developers start local. They want to run a process, point their agent at it, and get to work. The shift to hosted HTTP servers is real but has not overtaken the convenience of local tooling.
The ecosystem has gaps. Identity (23 servers, 3%) and Web (36 servers, 4.7%) are undersized relative to developer need. Web scraping, browser automation, and identity verification are common agent tasks with surprisingly thin server coverage.
FAQ
Q: How does AgentNDX decide which servers to list? A: Every server goes through a review process before it appears in the directory. We verify the endpoint, check documentation quality, and confirm the server follows MCP protocol conventions. Raw count in the wild is much higher — over 25,000 listings exist across aggregators — but curation is what makes a directory useful.
Q: What is the best category for a new MCP server? A: Build where the demand is and the supply is thin. Identity, Web, and Communication all have strong developer need relative to their server count. Data has the most demand but also the most competition.
Q: Will HTTP overtake stdio as the primary transport? A: For production use, yes. stdio will stay popular for local development and single-user setups, but any server that needs to handle multiple users, run remotely, or integrate with a hosted platform will use HTTP. The trend is already visible in the numbers.