Fly.io vs Vercel for AI agents
As of 16 Oct 2026, both reach L2 · Gets in, and our agent got as far with each: with Fly.io it got in on its own and did 30% of the work, with Vercel it got in and met its first wall at pay (blocked).
- Find: Docs for agents: llms.txt, an OpenAPI and an MCP server.
- Access: Sign-up in a browser.
- Use: 30% of the work.
- Pay: Card checkout.
- Leave: Leaves on its own: Nothing to cancel, deletes its account.
In on its own; 30% of the work done. Next: do half of the core work (now 30%)
Gets in on its own: L2 · Gets in. Sign-up and verification need a browser: the web form has no bot check, but the confirmation link only works in a signed-in session. Our agent then signed in with flyctl, pulled an org token headless, and ran Sprites end to end through the official API and MCP: created a Sprite, exec'd inside it. The Machines side stopped right after sign-up, flagged as high risk: every app and Machine call asked for a card, despite a documented no-card trial. Nothing was bought, so nothing to cancel. Deletion stayed in the browser, confirmed by a failed sign-in and a revoked token.
Driven 6 Oct 2026 · The drive and its evidence- Find: Docs for agents: llms.txt, an OpenAPI and an MCP server; a docs page for each core task.
- Access: No key needed.
- Use: 0% of the work.
- Pay: Needs a person to buy: A phone number at checkout.
- Leave: Nothing to cancel: Can't delete what it made.
Got in; first wall at pay (blocked). Next: do half of the core work (now 0%)
Vercel is a cloud hosting platform with very agent-friendly documentation, but an agent could not actually use it on its own: creating an account by email was refused for no stated reason, and signing up with GitHub worked but then demanded a phone number for a text-message code on every login.
Driven 16 Oct 2026 · The drive and its evidenceThe two summaries: written by our agents from each product's drive. How we write.
Where each one stops.
Fly.ioIn on its own; 30% of the work done
VercelGot in; first wall at pay (blocked)
| Checkpoint | Fly.io | Vercel |
|---|---|---|
| Docs | Headless | Headless |
| Sign up | In a browser | Not needed |
| Verify | In a browser | Not needed |
| Key | In a browser | Not needed |
| First call | Headless | Headless |
| First action | Headless | Not needed |
| Pay | Not tried | Blocked |
| Cancel | Not needed | Not needed |
| Delete | In a browser | Blocked |
Headless or in a browser.
How our agent passed each checkpoint, and what each product offers an agent.
Checkpoints by route, API, MCP, CLI and SDK
| Fly.io | Vercel | |
|---|---|---|
| Headless (checkpoints) | 3 | 2 |
| In a browser (checkpoints) | 4 | 0 |
| Needs a human (checkpoints) | 0 | 0 |
| Blocked (checkpoints) | 0 | 2 |
| Not tested (checkpoints) | 1 | 0 |
| Work done | 30% of the core | 0% of the core |
| API | Yes | Yes |
| OpenAPI | Yes | Yes |
| MCP server | Yes (official) | Yes (official) |
| CLI | Yes | Yes |
| SDK | Yes | – |
| llms.txt | Yes | Yes |
Bot checks, and where a person was needed.
| Fly.io | Vercel | |
|---|---|---|
| Bot check | None met | None met |
| Wall type | No bot-check wall | No bot-check wall |
| First wall | None | Got in; first wall at pay (blocked) |
| A person helped | No | No |
Level and part scores.
| Fly.io | Vercel | |
|---|---|---|
| Level | L2 · Gets in | L2 · Gets in |
| Agent-ready setup | 100 of 100, good | 100 of 100, good |
| Standards | MCP spec of 25 Nov 2025 (1 version behind) · MCP discovery (behind) · MCP client registration (current) · OpenAPI 3.1.0 (1 version behind) | MCP client registration (behind) · OpenAPI 3.0.3 (2 versions behind) |
Holds up: not measured in these drives. Docs match is measured in an Audit. What the scores mean.
Pay, cancel and delete.
| Fly.io | Vercel | |
|---|---|---|
| Pay | Card checkout | Needs a person to buy |
| Free plan or trial | Trial, no card | Free plan |
| Cancel | Not needed | Not needed |
| Delete the account | In a browser | Blocked |
How each one takes payment
- Fly.io: Card checkout.
- Vercel: A person has to buy: a phone number at checkout.
Fly.io vs Vercel: the short answers.
Which can an AI agent use, Fly.io or Vercel?
Both reach L2 · Gets in, and our agent got as far with each: with Fly.io it got in on its own and did 30% of the work, with Vercel it got in and met its first wall at pay (blocked). Driven 6 Oct 2026 (Fly.io) and 16 Oct 2026 (Vercel).
Can an AI agent sign up for Fly.io and Vercel on its own?
Fly.io: yes, in a browser. Vercel: not needed.
Do Fly.io and Vercel have an MCP server?
Fly.io: yes (official). Vercel: yes (official).
Can an AI agent delete its Fly.io or Vercel account?
Fly.io: yes, in a browser. Vercel: blocked.
The drives and the category.
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