How to measure agent revenue (GSV) from MCP tool calls
“Agents used our API” is a vanity metric. The question that funds the channel is: did those calls create revenue you can attribute?
Call logs are necessary, not sufficient
A hosted MCP proxy should log every tool invocation — tool name, latency, status, project. That’s how you see whether search_jobs or create_invoice actually gets used.
But a successful submit_application isn’t a hire. A create_checkout isn’t paid revenue until the charge clears. Attribution needs a human (or later, a webhook) to mark the outcome.
Manual GSV tagging (MVP)
Gross Service Value / revenue events on MakeCallable are manual in the MVP on purpose:
- Agent completes work via MCP tools
- Call log shows the trail
- When the business outcome closes, you tag amount + note on the project
You get a measurable thesis without pretending every HTTP 200 is a dollar.
What to track weekly
- Seats filled vs waitlisted
- Users with ≥1 real MCP client connect
- Successful proxied tool calls
- Manual GSV events per activated user
If calls are up and GSV is flat, the MCP surface isn’t on the money path — change which OpenAPI ops you expose.
What’s deferred
Auto attribution from webhooks, billing, and org RBAC wait until the capped loop proves activation quality. Measure first; automate second.
Related: Quickstart · FAQ