been building AI agent infrastructure for the past few months. The two things that kept biting me —
and kept coming up when I talked to other devs building agents — were runaway costs and agents doing
irreversible things without asking first.
So I built gvnr: an open-source MCP server that gives agents per-agent spend caps (hard-stop before a
call if the budget's gone) and a human approval gate (agent asks, you get a mobile link, you approve or
deny, agent waits). Both work as plain REST calls or MCP tools — no platform to adopt, no SDK.
It's live. You can get an API key in one curl command and try the approval gate for free (it doesn't burn
the trial ops). Source is at github.com/mightbesaad/gvnr.
Here's what I genuinely want to know from devs building in this space:
- Does the spend-cap shape match how you think about cost control, or do you manage that somewhere else
entirely? - Is the approval gate useful if it's email-only and single-approver, or does that make it a toy?
- What flag would stop you from wiring this into an agent you actually run?
Not fishing for encouragement — if this is solving the wrong problem, or solving it the wrong way, I'd
rather know now.