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Just One API for AI agents

Just One API gives unified access to public social media, creator, and ecommerce data across many platforms through metered endpoints. 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.

Connect Just One APISee the 288 actions ↓
Web data and scrapingAPI keyMCP + RESTjustoneapi.com
AUDIT LOG · JUST ONE APIPOLICY: acme-support
09:41:09 · claude · u_8f2write
just_one_api.zhihu_search
Zhihu Keyword Search✓ approved · approved by user
EVERY JUST ONE API CALL, ON THE RECORD
01 · USE CASES

What agents do in Just One API.

01

Look up product details

Look up an Amazon product's details and pricing for a competitive research report.

02

Search for a creator's videos

Search a platform like Bilibili for a creator's published videos to track content output.

03

Pull top reviews for a product

Pull the top customer reviews for a product to summarize common complaints.

02 · ACTIONS

288 Just One API actions, graded by risk.

Every Just One API action is tagged read, write or destructive, so one policy covers the whole app and new actions inherit the right default.

read

0

Look things up. Allowed by default.

  • No read actions.

write

288

Create and change things. Allow, or ask the user first.

  • just_one_api.zhihu_search
    Zhihu Keyword Search
  • just_one_api.reddit_search
    Reddit Keyword Search
  • just_one_api.toutiao_search
    Toutiao Web Keyword Search
  • just_one_api.twitter_search
    Twitter Search Timeline
  • just_one_api.weibo_get_fans
    Weibo User Fans
  • just_one_api.youtube_search
    YouTube General Search
  • just_one_api.weibo_hot_search
    Weibo Hot Search
  • just_one_api.weibo_search_all
    Weibo Keyword Search
  • just_one_api.douyin_hot_search
    Douyin (TikTok China) Hot Search
  • just_one_api.jd_get_item_price
    JD.com Product Price
  • just_one_api.llm_doubao_answer
    LLM Doubao Answer [Deprecated]
  • just_one_api.douyin_search_user
    Douyin (TikTok China) User Search
  • just_one_api.tiktok_search_post
    TikTok Post Search
  • just_one_api.tiktok_search_user
    TikTok User Search
  • just_one_api.weibo_tv_component
    Weibo TV Video Details
  • just_one_api.youku_search_video
    YOUKU Video Search
+ 272 MORE

destructive

0

Delete, cancel or archive. Ask first, or deny outright.

  • No destructive actions.
03 · HOW IT WORKS

Just One API in three steps.

  1. 01Your users connect Just One APIThey add their Just One API api key on Arc0 Connect, under your brand. It goes straight into the vault.
  2. 02You set the rulesReads run, and writes like “zhihu Keyword Search” can wait for the user to approve.
  3. 03Any agent can actYour agent calls Just One API through the Arc0 SDK or MCP, and so can Claude, ChatGPT and Cursor. Every call lands on the audit log.
POLICY.TS
await arc0.policies.set('just_one_api', {
  read: 'allow',
  write: 'ask',        // zhihu_search
  destructive: 'deny',  
})

# Claude Code: the same connection, one URL
$ claude mcp add --transport http arc0 \
    https://mcp.arc0.ai/u/u_8f2
04 · AUTH AND DATA

How Just One API connects.

Users add their Just One API 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 Just One API 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
05 · WORKS WITH

Use Just One API from any agent.

Claude
ChatGPT
Cursor
Codex
VS Code
OpenAI Agents SDK
Claude Agent SDK
Vercel AI SDK
Mastra
LangGraph
06 · RELATED

More web data and scraping apps.

Firecrawl30 actionsTavily5 actionsExa20 actionsAgentql3 actionsAgenty79 actionsAirtop10 actionsApify183 actionsOpenWeb Ninja164 actions
ALL WEB DATA AND SCRAPING APPS →
07 · FAQ

Just One API and Arc0, answered.

Q01

Can I use Just One API with Claude, ChatGPT or Cursor?

Yes. Connect Just One API 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 Just One API actions you allow.

Q02

How do users connect Just One API?

Users add their Just One API 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.

Q03

Which Just One API actions can my agent take?

288 in total: 0 read, 288 write and 0 destructive, such as “zhihu Keyword Search”. Your policies decide which of them each agent may call.

Q04

Can I make my agent read-only in Just One API?

Yes. Allow read actions and deny writes in the Just One API policy. Your agent can still look things up, and any write it attempts is blocked and logged.

Q05

Can my own backend call Just One API too?

Yes. The same Just One API connection is available over REST and through the Arc0 proxy, so your product and your agent share one connection per user.

Get started

Plug Just One API into your agent.

Your users connect Just One API once, under your brand. Your agent gets 288 actions behind your policies, with every call on the record.

Connect Just One APIBrowse all apps →

Free to build · MCP + REST · Audit log on every plan