Skip to content
Zumu

Model Context Protocol

Run your call center from Claude Code. Zumu speaks MCP in both directions.

An MCP call center is one where the tools point both ways. Zumu registers the MCP servers you already run, so an agent can call your tools while a caller is still on the line. Zumu also ships its own MCP server behind OAuth, so Claude Code, Cursor, or any MCP client can operate your agents, calls, knowledge and reports.

  • OAuth 2.0 with PKCE
  • Claude Code and Cursor
  • Your tools, called mid-call
  • Agents, calls, knowledge, reports

The session

One request, two tool calls, one approval

This is what running a call center from an editor looks like. The operator asks in plain English. The client picks the tools. The write stops for an approval, the read was allow-listed earlier so it does not, and the answer comes back carrying the same reason codes the reports use.

claude~/ops/after-hourszumu connectedMCP
switch our after-hours agent to the new
greeting, then read me yesterday’s
transfer reasons

I will update the prompt first, then pull the transfers.

zumuupdate_agent_prompt(agent: "After hours", version: "greeting-v4")MCP

Allow zumu to run update_agent_prompt?

1. Yes

2. Yes, and do not ask again for this tool

3. No, tell Claude what to do instead

prompt version saved · previous revision kept
zumulist_transfers(range: "yesterday", group_by: "reason_code")MCP
allow-listed in this project, so no prompt
transfers returned, grouped

Done. The after-hours agent is on the new greeting, and the revision before it is still there if you want it back. Yesterday’s transfers came back under four reason codes.

reason_code

caller_requested_human

outside_scope

frustration_detected

identity_check_failed

Each of those has the human leg recorded and graded, and none of those human minutes were billed.

An illustrative session. The tool names and the shape of the results are the ones the Zumu MCP server exposes. The transcript itself is not anyone’s data.

Direction one · Zumu as an MCP server

Operate the org from the editor you already have open

Add the Zumu MCP server to Claude Code, Cursor, or any client that speaks the protocol. The product carries the copy-paste setup for the first two on its own MCP page, so connecting is a paste and an approval rather than a project.

The connection is a real OAuth 2.0 authorization code exchange with PKCE. The client registers itself through dynamic client registration, you approve it on a consent screen, and the token that comes back is scoped to your organization. There is no shared secret to paste into a config file and none sitting in your shell history.

Claude Code or CursorYour Zumu organization

Your client calls Zumu’s tools

Platform MCP

  • list_calls
  • get_call
  • search_calls
  • list_transfers
  • update_agent_prompt

Knowledge MCP

  • retrieve
  • list_knowledge_bases
  • get_document

Two families, written the way the server advertises them. The names above are the ones worth knowing on day one rather than the whole surface.

Direction two · Zumu as an MCP client

Your agent calls your own tools while the caller is still on the line

Register the MCP servers you already run, over HTTP or over stdio. Zumu discovers the tools they expose and registers them on the agent, sanitizing the names so they stay valid for the model. Booking a ride, checking an order, looking up a member: whatever your server does, the agent can do mid-call.

The unglamorous half matters more. Servers are prewarmed before the greeting, so the first tool call of a call is not the one that pays the connection cost. A tool that hangs is cut off and tried once more. A server that cannot be reached does not end the call, and every attempt, including the failed one, lands in that call’s tool trace in the session report.

Your Zumu agent, mid-callYour MCP server

Zumu calls your tools

Transport
HTTP or stdio
Discovery
Tools registered on the agent automatically
Timeout
12 seconds per tool call, then one retry
Prewarm
Servers warmed before the greeting plays
Failure
The agent keeps the call and says so
Evidence
Every call carries a tool trace in its session report

Twelve seconds is the shipped default rather than a constant, and the retry is a single one. A tool that is slow twice is a tool your caller waits on, so the agent covers the wait out loud instead of going quiet.

What this replaces

11pm

The greeting is wrong and the fix is one sentence long

Getting to that one sentence is the part that costs you the evening. Sign in. Find the agent among the others. Open the right group in the editor. Change the prompt. Save the revision. Then open a second surface to work out whether last night’s transfers were about the same thing, because that is the actual question and the greeting was only a guess at it.

None of that is hard. All of it is friction, and friction at 11pm is how a wrong greeting stays wrong until Monday. With the MCP server connected, the same fix is a sentence typed where you already are. The clicking is the part that goes away.

  • The revision history still records the change, and the previous version is still one restore away.
  • The transfer reasons still come from the same reports your supervisors read in the morning.
  • Your team still gets the calls that need a person. This moves the console, not the work.

Questions

What developers ask about the MCP surface

Still have questions?

Bring the client you already use. We will connect it to a Zumu organization and you can drive it yourself.

It is a call center whose operations are exposed as Model Context Protocol tools, so an MCP client can read and change them directly. Zumu does this in both directions. It runs an MCP server, which lets Claude Code, Cursor, or any other MCP client list calls, search transcripts, list transfers, retrieve from a knowledge base and update an agent’s prompt. It is also an MCP client, which lets one of your voice agents call the MCP servers you already run while a caller is on the line.

Book a demo

Connect it to your editor and make one real change

We will connect the MCP server to a Claude Code session on your side, change one thing about an agent through it, and then read the revision it wrote back out. Bring the change you have been putting off.

  • No credit card for the demo
  • OAuth, not a pasted key
MCP Call Center: Voice AI in Claude Code | Zumu