New
The Zilla MCP Gateway is available — governed agent access to your APIs, services, and real-time data.
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Zilla MCP Gateway

Every API you run, served as MCP tools

One governed MCP endpoint for every internal API and remote MCP server. Tools generated from the OpenAPI specs you already maintain. Per-user identity on every call. Deployed inside your perimeter, so prompts, payloads, and credentials never leave it.

Install: docker pull ghcr.io/aklivity/zilla
zilla.yaml 17 lines · no tool code

The Production gap

MCP works in a demo. Production asks harder questions.

The Solution

A transparent proxy, not an execution engine.

Agents connect once. The gateway validates identity, applies authorization, and returns a unified catalog of tools, resources, and prompts across every MCP server and API —namespaced to prevent collisions.

Calls go straight to the real backend. Every MCP method is forwarded end to end. The gateway never terminates the protocol or runs tool logic.

MCP CLIENTSClaude · Claude Codestreamable http + jwtCursor · VS Codestreamable http + jwtYour custom agentany mcp clientZilla MCP Gatewayhttps://…/mcp1validatejwt on every request2federateone namespaced catalog3authorizeper user, per tool4forwardevery mcp method, end to endBACKENDSInternal APIsopenapi → toolsRemote MCP serversfederated, namespacedKafka topicsnative protocol

Core Capabilities

Six things most MCP gateways can't do.

URL-mode elicitation · SEP-1036

First-time OAuth, inside the MCP flow.

When an agent calls a tool the user hasn't authorized yet, the gateway returns a consent URL and the user approves in the browser. The gateway completes the exchange, caches the token per user, and the call succeeds.

URL-MODE ELICITATION · SEP-10361Tool call, no grantthe agent calls a tool the userhas not authorizedmcp: tools/call2Consent URL surfacedreturned inside the MCP response,not out of bandelicitation: url3Browser approvalthe user approves; the token iscached per useroauth 2.1 · per user4Call succeedsthe tool runs and the catalogupdatesnext tools/listnewly authorized tools appear in the next listing
URL-MODE ELICITATION · SEP-10361Tool call, no grantthe agent calls a tool the user has not authorizedmcp: tools/call2Consent URL surfacedreturned inside the MCP response, not out of bandelicitation: url3Browser approvalthe user approves; the token is cached per useroauth 2.1 · per user4Call succeedsthe tool runs and the catalog updatesnext tools/listnewly authorized tools appear in the next listing

The consent URL is returned inside the MCP response, not out of band.

The token is cached per user, so the next call needs no interruption.

Newly authorized tools appear in the next tools/list, per user.

No credential files, no service accounts, no manual token handling.

Context Budget

Tools that respect the context window.

Every session starts with the tools that matter most. The rest stay searchable, keeping context lean.

The catalog is tailored to each user’s token budget and permissions, so read-only users never waste context on write tools. Search follows the same access controls, while any authorized tool remains callable by name.

nothing is hidden from calls — only from the list

Integrations

Works with your existing stack.

Drop the gateway in front of what you already run. Any MCP client connects with an endpoint and a bearer token; identity, monitoring, and deployment plug into your existing tools.

Security

JWT

OAuth 2.1

Your IdP

TLS / mTLS

Monitoring

Prometheus

OpenTelemetry

CloudWatch

Syslog

Deployment

Kubernetes

AMI

Container

AWS Marketplace

Frequently asked questions

What is an MCP gateway?
Do agents or MCP servers need to be modified?
How does per-user identity actually work?
Which APIs and systems can become tools?
Can it validate or reshape tool payloads?
Where does it run, and where does my data go?

Ready to get started?

Get started on your own, or request a demo with one of our real-time data experts.

Explore pricing

Straightforward, usage-based pricing with no per-connection surprises — start free and scale when you are ready.

Pricing details

Join the Community

Trade notes with the engineers running Zilla in production, and get help from the team in Slack or Discord.