How to build a local MCP registry your security team will actually approve

AI agents are connecting to your production systems right now. The question is whether you know which ones, what they accessed, and who authorized them.

Here’s what you’ll learn in this post:

• Why an ungoverned MCP deployment is an audit and breach risk, not just a developer convenience problem
• The six decisions every platform team must make before deploying a registry
• How Stacklok turns MCP from an enterprise liability into a governed capability
• How to get a registry running in your environment today

The control plane you don’t have yet

Model Context Protocol (MCP) is the open protocol that standardizes how AI applications connect to external tools and data. Developers are already using it to wire Claude Code and Cursor into internal systems. Knowledge workers are using it to give AI assistants access to databases, ticketing platforms, and file systems.

Without a registry, each of these connections is uncontrolled. Credentials leak into local config files. Teams pull MCP servers from GitHub repositories, npm packages, and Docker Hub images with no attestation of where that code came from or what it does. And when something goes wrong, no one can answer the question that every security team will ask: “Which AI agent accessed our production database, and when?”

An MCP registry is the control plane that makes that question answerable. With a well-governed registry, MCP becomes an enterprise capability. Without one, it’s an enterprise liability.

We put together a detailed guide covering the key architectural decisions and concrete steps: Building a local MCP registry.

Six questions to answer before you build

1. Who is the registry for?

Developers and knowledge workers have different needs. Engineers want MCP servers connected to code repositories, CI/CD systems, and cloud APIs, and they’re comfortable with CLI configuration. Product managers, analysts, and finance teams interact through AI chat interfaces and need servers connected to documentation systems and communication tools. Most enterprises need to serve both groups through a single governance layer.

2. Where does the registry live?

For regulated industries, financial services, healthcare, and defense contractors, the entire MCP platform should run inside your VPC or on-premises environment. No tool call data or credential material should leave your perimeter. A hybrid model works for teams with lower regulatory overhead. SaaS-managed options are out of scope for most enterprises.

3. Who can use what?

The MCP specification doesn’t fully define backend authentication. Your registry must answer three identity questions for every tool call: who is the user (not just the service account), which servers is that user authorized to invoke, and what credential should reach the downstream resource? If you can’t answer all three before deploying, you’re creating audit exposure.

4. Do you trust the servers you’re running?

An MCP server is code that runs in your environment and makes outbound network calls on behalf of your users. A governed registry requires source attestation, image signing, vulnerability scanning, and change control. Any server that bypasses this approval process is a governance gap.

5. Can you answer what happened?

MCP tool calls have consequences. A complete observability picture requires per-request audit logs, metrics on request rate and token consumption per server and per user, end-to-end traces correlating MCP calls with downstream API calls, and alerting on anomalous usage patterns.

6. What can each server access?

An MCP server should have access to exactly the resources it needs, nothing more. Without a governance layer, a server running on a developer’s laptop has access to the local filesystem, network interfaces, and environment variables, all of which may contain credentials for other systems.

How Stacklok solves this

The Stacklok MCP platform addresses each of these questions as first-class platform capabilities, not afterthoughts.

Stacklok deploys as a Kubernetes Operator, integrating with your existing infrastructure rather than introducing a new SaaS dependency. An embedded authorization server supports OIDC and OAuth 2.0 SSO with native integrations for Okta, Microsoft Entra ID, and Google Workspace. Per-request identity tokens replace locally stored credentials, so when an analyst queries a data warehouse, that request arrives with a credential scoped to that analyst, not a shared service account.

Every MCP server runs in an isolated container with configurable network and filesystem permissions defined in JSON profiles. A server for a documentation system gets access to the documentation API. That’s it. Even a compromised server package has a bounded blast radius.

For observability, Stacklok implements the OpenTelemetry MCP semantic conventions and exposes Prometheus metrics, with out-of-box integration for Grafana, Datadog, Honeycomb, Splunk, and New Relic.

The curated registry workflow requires explicit admin approval before any server reaches users. Server definitions are Kubernetes CRDs in a version-controlled repository, so adding, updating, or removing a server is a code change with a full audit trail, reviewer sign-off, and rollback capability.

What to do in your first 90 days

Start with your identity layer. Connect Stacklok to your identity provider before onboarding a single server. Every other control depends on knowing who the user is.

Then map your catalog. Large enterprises typically need 20 to 60 MCP servers in their initial deployment. Document each server’s source, the backend systems it accesses, which teams need it, the data classification of what it can return, and any applicable compliance requirements. Commit that manifest to version control. It becomes the input to your GitOps pipeline.

Start small. Onboard three to five high-demand, low-sensitivity servers first. Build operational confidence before expanding.

The full six-step guide, including Helm installation commands, CRD examples, and day-two operations processes, is in Building a local MCP registry.

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Want to see what Stacklok can do for your organization? Book a demo or get started right away with ToolHive, our open source project. The registry quickstart will have you up and running in minutes. Join the conversation and engage directly with our team on Discord.