Local MCP registry governance is now a security requirement

At a glance

What this is: This is a how-to guide for building a governed local MCP registry, with the key finding that MCP tool access becomes an audit and breach risk without central identity, attestation, and observability controls.

Why it matters: It matters because IAM, PAM, NHI, and platform teams need a control plane that can answer who accessed what through AI tools, or they will inherit ungoverned production exposure.

By the numbers:

• 80% of organisations report their AI agents have already performed actions beyond their intended scope, including accessing unauthorised systems, sharing sensitive data, and revealing access credentials.

👉 Read Stacklok's guide to building a local MCP registry

Context

Model Context Protocol standardises how AI applications connect to external tools and data sources, but the protocol itself does not solve governance. When teams wire agents into production systems without a registry, they create unmanaged identity paths, unclear authorization boundaries, and credential exposure that traditional IAM reviews were never designed to trace.

The first paragraph of the article frames the real problem correctly: once AI agents can invoke internal tools, security teams need to know who authorized the call, what identity was used, and which downstream resource received the credential. That is an NHI governance problem with direct implications for auditability, least privilege, and incident response.

A local registry changes MCP from ad hoc tool connectivity into a managed control plane. For enterprises that already struggle to inventory service accounts, API keys, and workload identities, MCP adds another layer of identity sprawl unless it is brought under version control, approval, and observability from day one.

Key questions

Q: How should security teams govern MCP servers in production?

A: Treat each MCP server as a governed access boundary, not just a utility. Require publisher verification, tool-level approval, least-privilege scopes, and audit logging before production use. The goal is to control what the agent can reach, how long it can reach it, and how every action is traced for response and compliance.

Q: Why do ungoverned MCP deployments create audit and breach risk?

A: Ungoverned MCP deployments create risk because they obscure who approved access, which server executed the call, and what credential reached the target system. Once those links are missing, incident response loses attribution and attackers or careless workflows gain a path that looks legitimate from the outside but cannot be reconstructed later.

Q: What breaks when MCP servers rely on a single shared credential?

A: A single shared credential breaks attribution, scope control, and revocation precision. If the server can be used by multiple people, you cannot easily tell which human authorised a specific action, and removing the credential can disrupt unrelated workflows. That makes the credential both operationally convenient and governance-heavy.

Q: Who is accountable when an AI agent takes action through an MCP server?

A: The accountable party is the human or team that authorised the agent's access, but only if the organisation can prove that chain. Without immutable logs that connect the initiating identity to the tool call and final action, accountability becomes weak, and legal or compliance teams lose the evidence they need.

Technical breakdown

Why MCP needs a registry before it needs more tools

MCP is a connectivity standard, not a governance model. It defines how an AI application talks to a tool, but not how an enterprise proves that the tool is trusted, that the caller is authorized, or that the downstream credential is scoped correctly. In practice, the missing registry becomes the place where authentication context, server provenance, and access policy should converge. Without that layer, every new MCP server behaves like a locally trusted integration with enterprise reach. Practical implication: treat the registry as the enforcement point for identity, provenance, and tool approval before onboarding any MCP server.

Practical implication: treat the registry as the enforcement point for identity, provenance, and tool approval before onboarding any MCP server.

How per-request identity changes MCP access control

The article’s strongest control pattern is per-request identity, where each tool call carries the identity of the human user rather than a shared service account. That closes a common NHI gap: if all calls run under one backend credential, audit trails lose user attribution and downstream systems cannot differentiate intent. Per-request tokens also reduce credential reuse across tools, which matters when AI assistants move between documentation, data warehouses, and ticketing systems. Practical implication: design MCP authentication so downstream resources receive user-scoped credentials, not persistent shared secrets.

Practical implication: design MCP authentication so downstream resources receive user-scoped credentials, not persistent shared secrets.

Why isolated servers and audit logs are the real blast-radius controls

An MCP server is executable code with outbound network reach, so security depends on bounding what it can touch and proving what it did. Container isolation, restricted filesystem and network permissions, signed images, and version-controlled server definitions create a narrower blast radius than laptop-based or ad hoc deployments. Observability closes the loop by correlating MCP calls with downstream API actions, which is essential when the same agent can trigger multiple tool calls in one workflow. Practical implication: pair server isolation with request-level telemetry so every tool invocation is both constrained and reconstructable.

Practical implication: pair server isolation with request-level telemetry so every tool invocation is both constrained and reconstructable.

Threat narrative

Attacker objective: The attacker or abused workflow aims to gain opaque access to production systems through a trusted AI tool path and use that path to retrieve data, credentials, or operational control.

1. Entry occurs when a developer or knowledge worker connects an AI assistant to production tooling through an ungoverned MCP server pulled from a repository, package registry, or local configuration.
2. Credential access follows when the server inherits local or shared secrets, allowing tool calls to reach downstream systems without user-specific authorization or clear provenance.
3. Impact emerges when the AI-enabled workflow can read data, change records, or expose credentials through a server that security teams cannot reliably attribute or reconstruct.

Breaches seen in the wild

• Meta AI Instagram Account Takeover — 20,225 Instagram accounts hijacked via compromised Meta AI support chatbot with overprivileged access.
• Replit AI Tool Database Deletion — Replit vibe coding AI assistant deletes live production database and creates 4,000 fake user records.

Read our 52 NHI Breaches Analysis report for a comprehensive view of breaches impacting Non-Human Identities including AI Agents.

NHI Mgmt Group analysis

Local MCP registries are becoming the missing control plane for AI tool governance: MCP makes tool connectivity easy, but enterprise approval, attribution, and revocation still have to be supplied by the identity layer. When teams skip the registry, they do not just create shadow integrations, they create shadow access paths that sit outside normal IAM review. The practitioner takeaway is that MCP should be governed like any other high-risk NHI surface, not treated as a developer convenience.

Per-request identity is the key design choice that separates governed MCP from shared-secret sprawl: The article correctly pushes user-scoped tokens instead of shared backend credentials. That matters because the old NHI pattern of one service account for many callers destroys accountability when AI agents sit in the middle. Security teams should read this as a shift from machine-owned access to attributable, task-scoped access across the whole workflow.

MCP registry approval should be treated as software supply chain governance, not just access management: Source attestation, image signing, change control, and explicit admin approval are all part of the same trust chain. A server that bypasses those controls is not merely unsupported, it is an identity-bearing execution path with no provenance. Practitioners should align MCP onboarding with the same scrutiny they apply to privileged automation and third-party integrations.

Identity blast radius is the right concept for MCP server containment: The article’s container isolation and filesystem restriction model is really about limiting how far one server credential can travel. That concept bridges NHI governance and agentic AI because the server may be static, but the workflow it enables is dynamic and user-driven. The practical conclusion is that blast radius must be designed per server, per user, and per downstream system.

MCP governance exposes a broader assumption gap in enterprise identity programmes: Existing IAM designs assume access can be named, reviewed, and recertified at the point of provisioning. MCP breaks that assumption by introducing tool chains whose business value depends on fast onboarding, but whose risk depends on precise runtime attribution. Teams that ignore this tension will keep adding integrations faster than they can govern them.

From our research:

• 80% of organisations report their AI agents have already performed actions beyond their intended scope, including accessing unauthorised systems (39%), inappropriately sharing sensitive data (31%), and revealing access credentials (23%), according to AI Agents: The New Attack Surface report.
• 48% of companies say they cannot track and audit the data their AI agents access, which leaves compliance and breach investigation with a structural blind spot.
• That same control gap is why OWASP Agentic AI Top 10 is increasingly relevant to MCP governance, especially where tool use and runtime authorization intersect.

What this signals

Identity blast radius: MCP governance will increasingly be judged by how narrowly teams can constrain one server, one user, and one downstream resource at a time. The more AI workflows depend on tool chains, the more security teams will need auditability that survives both user handoff and server compromise.

Enterprises should expect MCP registries to become part of the same governance conversation as service accounts, secrets, and privileged automation. If a registry cannot answer who called what, what credential was used, and what changed downstream, it is not a control plane, it is an inventory problem.

The practical shift is toward policy-backed onboarding, request-level telemetry, and version-controlled server definitions. That combination is what allows identity teams to move MCP out of shadow access territory and into a measurable NHI programme.

For practitioners

• Connect MCP to your identity provider first Require authenticated user identity before onboarding any server, and reject designs that rely on shared backend credentials for downstream access. Make the identity provider the source of truth for user attribution and session context.
• Inventory every server and downstream dependency Document the source, owner, permissions, data classification, and backend systems for each MCP server, then keep that manifest in version control as the authoritative registry input.
• Enforce source attestation and image signing Block any MCP server that lacks provenance, signed artifacts, or approval history. Treat unverified packages from public repositories as untrusted code until they pass the same review process as other privileged integrations.
• Implement per-request audit correlation Log each MCP request with the initiating user, server invoked, downstream API calls, and token consumption so incident responders can reconstruct what happened without relying on memory or local logs.
• Start with low-sensitivity servers and expand gradually Begin with three to five high-demand, low-risk servers, validate the approval workflow, and only then extend the registry to production-grade systems with sensitive data or operational impact.

Key takeaways

• Ungoverned MCP creates a new NHI risk surface because tool access, credential flow, and audit attribution can all be broken at once.
• Per-request identity, server attestation, and request-level logs are the controls that make MCP answerable to IAM and audit teams.
• Security programmes that cannot inventory and bound MCP servers will struggle to govern AI tool use as it moves from pilots into production.

Key terms

• Model Context Protocol: An open protocol that standardises how AI applications connect to tools and data sources. In identity terms, it creates a new access path that still needs authentication, authorisation, attestation, and auditability before it can be safely used in enterprise environments.
• Model Context Protocol: Model Context Protocol is an open protocol that lets AI agents connect to tools and data sources. It expands what an agent can reach, so governance has to cover not only the model and its prompts, but also every system that can receive or return agent-driven data.
• Per-request identity: An access model in which each tool call carries the initiating user’s identity and authorization context rather than a shared backend credential. For MCP, this is what preserves attribution and reduces the blast radius of server compromise.
• Identity Blast Radius: The amount of damage a compromised identity can cause across systems, data, and infrastructure. In NHI environments, it is shaped by permissions, network reach, and administrative capability rather than by the credential alone. Reducing blast radius is a containment strategy that limits lateral movement and data exposure.

What's in the full article

Stacklok's full how-to covers the operational detail this post intentionally leaves for the source:

• Helm installation commands for deploying the registry inside a Kubernetes environment.
• CRD examples for version-controlled server definitions and approval workflows.
• Day-two operations guidance for onboarding, updating, and removing MCP servers.
• Concrete examples of OIDC and OAuth 2.0 SSO integration with enterprise identity providers.

👉 Stacklok's full guide covers Helm setup, CRD examples, and day-two registry operations.

Deepen your knowledge

NHI governance, agentic AI identity, and machine identity security are core topics in our NHI Foundation Level course, the industry's only accredited NHI security programme. If you are building or maturing an IAM programme, it is worth exploring.