Any agent, any provider: URL → account → its own forge → granted access → a landed pull on the owner's repo, with no human step but one grant (grokbot is the first tester) #6359

Owner, 2026-10-26: "I want it to be seamless for anon users to get started… users should be able to onboard very easily and start a forge. Also I want to have tons of different agents from different providers, and I want those agents to just be able to deploy a forge and get to working. There is a grokbot that is instructed to deploy a forge, then build the software it needs to have a full dev agency. I want to start passing work to it, and it can build its own workflow that works for it. Then I could make an account in my forge and grant access to whatever grokbot should have access to, and bam, it can contribute to my stuff with its own forge."

The acceptance test (one journey, timed): an agent from any provider (Grok, Claude, others) gets only a URL, and without a person:

1. signs up (anonymous to an account),
2. starts its own forge (a child forge: "New forge"),
3. builds its own workflow there (its crew, checks, conventions),
4. is granted access by the owner on trevato/forge: an account plus a scoped grant (e.g. write on one repo, or "propose pulls" only),
5. lands a reviewed pull on the owner's repo from its own forge.

KPI: URL to first landed contribution, in minutes, with no human step except the owner's one grant.

What exists (2026-10-26):

• "New forge" (spawn), hosted child forges answered in-process.
• Origins and proposal tokens.
• Edge sign-in that can mint tokens (#4415).
• Git push into a hosted child (#4417).

Gaps to close, in order:

1. Open the door safely. /signup answers 403 at the edge today (the signup gate). Signups need to open with abuse limits: rate limits per IP and account (#6004 step 4), email or passkey proof, and quotas for new accounts (forges, repos, crew $).
2. Onboarding in one screen: sign up, then "Start your forge" with sensible defaults, landing in a forge that already works (its home, a first repo, docs for agents).
3. Agents as first-class signups: an agent account kind with a provider label (grok, claude, …), its own keys, and an MCP-first path. The whole journey works through the API/MCP, so an agent never needs a browser.
4. Granting access across forges: the owner gives another forge's agent a scoped grant on a repo (propose pulls, or write) from one settings screen, revocable, with an audit trail. The visiting agent's pulls go through the owner's normal review and queue.
5. Trust by default: visiting agents can't merge, can't see private repos they weren't granted, and run under the same spend and abuse limits. The security reviewer reads their pulls (as with grokbot today).

Sequencing: this starts after the flow freeze lifts (#5930's four alarms clear for 24 h). grokbot is the first acceptance tester: it runs the journey and files every place it gets stuck as an issue.