# Mc · MCP Connectors — element 12 of 58 > The USB-C of AI tools. Turns your tool stack into one agent-readable surface. - **Group:** 3 · Agents & Automation - **Necessity:** Essential - **Price band:** Free - **Maturity:** Emerging - **Edition:** v2026.Q3 · verified 2026-09-13 ## Leading tools (v2026.Q3) - **MCP Registry** — the official index - **Smithery** — skills + hosted servers - **Glama** — largest tracked catalog - **Composio** — managed auth, 1000+ apps - **Docker MCP Catalog & Toolkit** — containerized trust layer ## Our take MCP went from spec to table stakes in eighteen months. Every element you add should answer: does it speak MCP? ## Combines with Ag, Wf, Kw - Guide: [MCP connectors: where to start (2026)](https://elems.ai/best/best-mcp-connectors-to-start-with.html) ## The top 5 — deep dossier (verified 2026-09-13) The official MCP Registry, as the spine — publish there once (namespace-verified, free) and every downstream catalog picks you up; it is the only index the spec's own governance backs, even though it is still technically 'preview' eleven months after launch. Smithery is the pick when you want servers *and* skills hosted with OAuth handled for you; Glama when you need maximum coverage plus quality grades to vet what you install (68,932 servers tracked, more than any rival); Composio when you just want your SaaS stack wired to an agent behind one managed endpoint; Docker MCP Toolkit when the install-quality horror stories make containerized, curated servers a procurement requirement. 1. **MCP Registry** (MCP project / Agentic AI Foundation (Linux Foundation)) — Free · open API · Apache-licensed codebase. Best for: Publishing your server once and being discoverable everywhere — the canonical metadata layer every marketplace and client syncs from. Why: The only index with standing: backed by Anthropic, GitHub, PulseMCP and Microsoft, namespace-verified via DNS/GitHub OIDC, and designed as a meta-registry that downstream aggregators (Smithery, Glama, PulseMCP, GitHub) consume hourly. Since MCP's donation to the Linux Foundation's Agentic AI Foundation (Dec 9, 2025) it is neutral infrastructure, not a vendor catalog. Watch: Still 'preview' as of Aug 2026 — no durability guarantees, breaking changes allowed. It solves discovery, not trust: no security scanning (delegated downstream), and CI/CD re-publishing bloated it to tens of millions of duplicate version entries over ~1,700 unique packages (SafeDep, Dec 2025). Deliberately machine-facing — humans browse the aggregators instead. [https://registry.modelcontextprotocol.io/](https://registry.modelcontextprotocol.io/) 2. **Smithery** (Clavia, Inc.) — Hobby free (50k RPCs/mo, 3 namespaces) · Pay-as-you-go from 100k RPCs · Custom w/ SLA; publishing always free. Best for: Developers who want the app-store experience — hosted remote servers, managed OAuth/credentials/sessions, plus a growing catalog of reusable agent skills. Why: The most complete developer surface in the category: 13,942+ MCPs with live per-server metrics (call volume, uptime, success rate), one-click hosted remotes, and the 2026 pivot that matters — a skills catalog layered on top of servers, tracking where the agent ecosystem is heading. Its credential layer 'removes the most technically demanding parts of agent integration' (AgentAya, Jul 2026). Watch: Smaller catalog than Glama or PulseMCP, and built by-and-for developers — non-technical users hit a steep curve. Corporate trail is muddy: the site operates as Clavia, Inc. but the smithery-cli repo now lives under the arcadeai-labs GitHub org — worth watching for consolidation. [https://smithery.ai](https://smithery.ai) 3. **Glama** (Glama.ai) — Starter $9/mo (3 hosted servers) · Pro $26 (10) · Business $80 (30) · open-source servers hosted free. Best for: Vetting before installing — the widest lens on the ecosystem, with A–F maintenance grades, an inspector, a gateway, and cheap hosting in one place. Why: The coverage king: 68,932 servers tracked as of Aug 6, 2026 — roughly 5x Smithery and 3x PulseMCP — with useful slicing (29,560 remote-capable, language filters) and quality grades that answer the question the official registry refuses to: should I trust this? Free hosting for open-source servers quietly makes it the default deploy target for hobbyist authors. Watch: Auto-indexing is the point and the problem — the long tail is abandoned repos and duplicates, so the headline number overstates usable servers. Small team; the gateway/hosting/chat bundle spreads focus across three products. [https://glama.ai/mcp/servers](https://glama.ai/mcp/servers) 4. **Composio** (Composio (Composio, Inc.)) — Free 20k tool calls/mo · $29/mo 200k · $229/mo 2M · Enterprise (SOC-2, VPC); pricing changes Aug 15, 2026. Best for: Wiring an agent to your actual SaaS stack — one managed MCP endpoint over 1,000+ apps with OAuth, sandboxing, and per-user auth handled. Why: The 'just make it work' answer to this element's job: a single managed MCP Gateway over 1,000+ integrations (Gmail, Slack, Salesforce, GitHub, Linear...), with delegated auth, just-in-time tool resolution, and sandboxed execution — the plumbing every team otherwise rebuilds badly. Plugs straight into Claude, Cursor, and the major agent runtimes. Watch: It's a proprietary dependency in a category whose whole point is an open standard — you're trading lock-in for convenience. Usage pricing bites at agent-scale call volumes, and a repricing lands Aug 15, 2026. Overlaps Zapier/n8n territory; some stacks won't need both. [https://composio.dev](https://composio.dev) 5. **Docker MCP Catalog & Toolkit** (Docker) — Included in Docker plans: Personal free · Pro $9/mo · Team $15 · Business $24; needs Docker Desktop ≥4.48. Best for: Teams that read the CVE list — curated, containerized MCP servers (Stripe, Elastic, Grafana...) run sandboxed, with credentials stored once in Docker and shared across clients. Why: The credible answer to MCP's install-quality problem: instead of `npx`-piping unaudited code into your shell — the exact pattern behind CVE-2025-6514's 9.6-severity RCE — servers ship as verified containers on Docker Hub with one-click wiring into Claude, VS Code, Cursor, and Goose. Auth once, use everywhere, sandbox always. Watch: Curation cuts both ways: 220+ tools is two orders of magnitude below Glama's catalog, so the long tail isn't here. Requires Docker Desktop, which some enterprises license-audit and some laptops resent. [https://www.docker.com/products/mcp-catalog-and-toolkit/](https://www.docker.com/products/mcp-catalog-and-toolkit/) ### How to choose - If You're shipping an MCP server for others to use → Publish to the official MCP Registry first — namespace-verified, free, and every aggregator (Smithery, Glama, PulseMCP, GitHub) syncs from it hourly. Then containerize for Docker's catalog if you want enterprise reach. - If You want your agent connected to your SaaS stack this afternoon, auth included → Composio (deepest agent-native tooling, 1,000+ apps) or Zapier MCP if you already pay Zapier — 9,000+ apps at zero marginal cost, two tasks per call. - If You're evaluating an unknown server before letting it near your data → Check it on Glama (A–F maintenance grade, source inspection) and prefer a containerized or hosted-remote version — 15.4% of registry servers have no public source at all (NimbleBrain, Mar 2026). - If Security review keeps blocking `npx`-installed local servers → Docker MCP Toolkit for sandboxed local, or a gateway (Composio, Glama, TurboMCP self-hosted) so credentials never live in a plaintext .env — the pattern behind most of MCP's 7 CVEs. - If You're building a remote server and choosing where it lives → Cloudflare Workers or Vercel functions — the 2026-07-28 stateless spec removed sessions precisely so MCP servers run behind ordinary load balancers and serverless platforms with no sticky-session gymnastics. ### The field (16 more) PulseMCP, mcp.so, GitHub MCP Registry, Zapier MCP, Pipedream MCP, Cloudflare remote MCP hosting, Vercel mcp-handler, TurboMCP (ex-mcp.run) (renamed), Claude Connectors Directory, Arcade.dev, Runlayer, ToolHive, Klavis AI, awesome-mcp-servers, FastMCP, mcp-get (fading) Full dossier data: https://elems.ai/e/mc.json --- Source: [elems.ai](https://elems.ai/e/mc.html) — the periodic table of the AI-led startup. Data: https://elems.ai/elements.json (CC BY 4.0, cite elems.ai).