U301 for AI agents
U301 is a URL shortener, used by teams that want branded, trackable short links for campaigns and shares. Connect it once through Arc0, and your agent, or Claude, ChatGPT and Cursor, can use it through one MCP endpoint, limited to what each user approved.
What agents do in U301.
Shorten a long URL
Create a short link for a long URL using an available domain.
List domains available for shortening
Check which domains can be used for a new short link, a read-only lookup.
Confirm before deleting a shortened link
Check with the user before deleting a shortened link, since existing shares would break.
3 U301 actions, graded by risk.
Every U301 action is tagged read, write or destructive, so one policy covers the whole app and new actions inherit the right default.
read
1Look things up. Allowed by default.
- u301.list_shorten_domainsList available domains for URL shortening
write
1Create and change things. Allow, or ask the user first.
- u301.shorten_linkShorten a long URL
destructive
1Delete, cancel or archive. Ask first, or deny outright.
- u301.delete_linkDelete a shortened link
U301 in three steps.
- 01Your users connect U301They add their U301 api key on Arc0 Connect, under your brand. It goes straight into the vault.
- 02You set the rulesReads run, writes like “shorten a long URL” can wait for the user, and “delete a shortened link” can be denied outright.
- 03Any agent can actYour agent calls U301 through the Arc0 SDK or MCP, and so can Claude, ChatGPT and Cursor. Every call lands on the audit log.
await arc0.policies.set('u301', { read: 'allow', write: 'ask', // shorten_link destructive: 'deny', // delete_link }) # Claude Code: the same connection, one URL $ claude mcp add --transport http arc0 \ https://mcp.arc0.ai/u/u_8f2
How U301 connects.
Users add their U301 api key on Arc0 Connect. It is encrypted in the vault, never shown to the model, and each user can rotate or revoke it at any time.
The same U301 connection serves your agent over MCP and your own backend over REST and the proxy, so a user connects once. How Arc0 handles credentials →
- AUTH
- API key
- CREDENTIALS
- Per-tenant encrypted vault
- MODEL SEES
- Results only, never credentials
- AUDIT LOG
- Every call, on every plan
Use U301 from any agent.
ClaudeChatGPTCursor
Codex
VS CodeOpenAI Agents SDKClaude Agent SDK
Vercel AI SDK
Mastra
LangGraph
U301 and Arc0, answered.
Can I use U301 with Claude, ChatGPT or Cursor?
Yes. Connect U301 to Arc0 once, then add your Arc0 MCP URL to Claude, ChatGPT, Cursor, Claude Code or any other remote-MCP client. Each assistant only gets the U301 actions you allow.
How do users connect U301?
Users add their U301 api key on Arc0 Connect. It is encrypted in the vault, never shown to the model, and each user can rotate or revoke it at any time.
Which U301 actions can my agent take?
3 in total: 1 read, 1 write and 1 destructive, such as “shorten a long URL”. Your policies decide which of them each agent may call.
Can I stop my agent from deleting things in U301?
Yes. Actions like “delete a shortened link” are graded destructive. Set destructive actions to deny, or to ask so the user approves each one, and blocked calls still show up on the audit log.
Can my own backend call U301 too?
Yes. The same U301 connection is available over REST and through the Arc0 proxy, so your product and your agent share one connection per user.
Plug U301 into your agent.
Your users connect U301 once, under your brand. Your agent gets 3 actions behind your policies, with every call on the record.
Free to build · MCP + REST · Audit log on every plan