Architecture - Metaphi AI

Four blocks

Block	Question	What does it
Gate	Who may do this, on which repository?	One MCP endpoint. Hum sign-in gives you a tier. GitHub decides at every call: a launch needs push, a read needs read. Long work comes back as an MCP task.
Run	Where and how does the work execute?	Modal workers: task CI, task runs, authoring, the forge loop, consults. Harbor trials in Modal sandboxes, labelled by run and reaped when it ends. Agent sessions on the Claude Agent SDK.
Route	Which model, through which provider, at what cost?	The Nunatak model gateway, for every model call a trial makes. Models are catalog ids. A sandbox holds a short-lived trial token, never a provider key. Each rollout row carries its gateway cost. Judges and authoring sessions call their own provider from the worker.
Record	What happened, and can it be trusted?	Your repository’s own run volume. One row per rollout. Every failure typed at its source; infrastructure is never scored as a model’s 0.

3C on the blocks

Each 3C step is one call, and every call passes through all four blocks.

Step	Run	Route	Record
Pre-run Check	Task CI legs, each in its own sandbox	The validate `conduct` leg through the gateway; judged checks call their provider	`<task>/ci/<run id>/`, `<task>/validate/<run id>/`
Conduct	k Harbor trials per model	Every trial’s model calls	`<task>/eval/<run id>/<model slug>/`
Post-run Check	The trajectory reviewer	The judge model, called from the worker	`trajectory_report.json` beside each trial
Consult	The asking session, or the Slack thread	The reply agent, called from the worker	The consult record, answers under `<task>/sme/`

Gate in detail

A tier lists the tools you may call. A tool above it is not listed, and a call to it is refused with the tier it needs.
Whether a call goes through is the owner’s answer at the call. For a repository that is GitHub, asked as you.
A task, a consult or a parked pass is read, listed or cancelled only by the person who started it.

Record in detail

Runs land on a volume named after the repository (owner--name, lowercased), in the task’s directory, the bundle directory’s last segment:

<task>/harbor/                         the bundle as it last ran
<task>/ci/<run id>/                    every task CI check
<task>/validate/<run id>/              every validate
<task>/eval/<run id>/<model slug>/     every run
<task>/calibrate/<run id>/             every calibrate session

Nothing is overwritten except harbor/. Each record names the repository and the commit it ran at.