generated: '2026-08-13'
method: searched
status: published
source: https://docs.cello.so/mcp/introduction
server:
  name: cello
  transport: http
  url: https://mcp.cello.so/mcp
  sandbox_url: https://mcp.sandbox.cello.so/mcp
  auth: oauth
docs: https://docs.cello.so/mcp/connect
tool_reference: https://docs.cello.so/mcp/tools
enablement: An account admin must turn the MCP server on in the Cello Portal under Integrations -> MCP
  and copy the account's MCP Server URL before any client can connect.
clients:
- Claude
- Claude Code
- Cursor
- VS Code
- Windsurf
- Lovable
- Replit
posture:
  read_only: true
  note: Cello states all MCP tools are currently read-only; to make a change the assistant points the
    user at the Cello Portal. No write tool is published, even though the protected-resource metadata
    advertises an mcp:write scope.
tools:
- name: cello_get_program_metrics
  audience: growth
  description: Complete referral program metrics in one call — lifetime referrer and new-user funnel totals
    plus ARR, pre-calculated monthly and weekly trends, weekly/monthly history time series, and industry
    benchmarks segmented by GTM motion (Free Trial, Freemium, Demo Only, Overall) with median and best-in-class
    lines.
- name: cello_get_referrers
  audience: growth
  description: Find referrers, optionally filtered and sorted by engagement or performance metrics.
  parameters:
  - name: filter
    note: matches ucc, email, product user id, or referrer id
  - name: page
    note: 1-indexed, 10 per page
  - name: sort
    note: defaults to net new ARR; also revenue, signups, purchases, unique views, recent activity
- name: cello_get_top_referrers
  audience: growth
  description: Top-performing referrers sorted by net new ARR, descending.
  parameters:
  - name: page
    note: 1-indexed, 10 per page
- name: cello_get_integration_status
  audience: developer
  description: Health of the four integration components (referral widget, attribution widget, signup
    tracking, purchase tracking) — per-component connectionStatus of connected, connectedWithWarnings
    or notConnected, optional warningType, and lastEventReceived.
- name: cello_get_events
  audience: developer
  description: Recent webhook and API events Cello received, newest first, with source, overall validation
    status, timestamp, and a per-field payload breakdown (ucc, productUserId, email, customerId).
- name: cello_get_recommendations
  audience: both
  description: Prioritized best-practice recommendations grouped by activation, sharing and conversion,
    with completed/pending status, effort and impact labels, and a top-priority callout.
- name: search_cello
  audience: both
  description: Search the Cello knowledge base for documentation, code examples, API references and guides.
- name: query_docs_filesystem_cello
  audience: both
  description: Read-only query interface over an in-memory filesystem of the Cello documentation pages
    and OpenAPI specs — read a page by path, exact keyword or regex search, explore the docs structure.
authorization:
  flow: oauth
  protected_resource_metadata: ../well-known/cello-oauth-protected-resource.json
  authorization_server: https://auth.cello.so
  authorization_server_metadata: ../well-known/cello-oauth-authorization-server.json
  scopes:
  - mcp:read
  - mcp:write
  dynamic_client_registration: https://auth.cello.so/oauth2/register
  pkce: S256
  ref: ../scopes/cello-scopes.yml
  note: RFC 9728 protected-resource metadata is served at https://mcp.cello.so/.well-known/oauth-protected-resource
    and is what the 401 challenge points clients at. Cello's docs describe the flow in prose ("your client
    opens a browser window... there's no token to generate") and never mention the metadata document or
    the scopes.
crosswalk: cello-tool-crosswalk.yml
deployment:
  mode: remote
  endpoint: https://mcp.cello.so/mcp
  verified: probed
  probe: gated
  checked: '2026-08-12'
  source: catalog MCP census
x-evidence:
  fetched: '2026-08-13'
  probes:
  - url: https://mcp.cello.so/mcp
    http_status: 401
    method: POST {"jsonrpc":"2.0","id":1,"method":"tools/list"}
    note: 'Returns WWW-Authenticate: Bearer resource_metadata="https://mcp.cello.so/.well-known/oauth-protected-resource"
      — the endpoint is live and correctly implements the MCP OAuth challenge. Tool schemas require an
      authenticated introspection; the tool list here is Cello''s published reference, not a guess.'
  - url: https://mcp.sandbox.cello.so/mcp
    http_status: 401
    note: sandbox MCP endpoint is live and gated the same way
  - url: https://mcp.cello.so/.well-known/oauth-protected-resource
    http_status: 200
  - url: https://docs.cello.so/mcp/tools.md
    http_status: 200