Agent3 Hub#

Agent3 Hub is an open registry for AI agents, MCP servers, and APIs. It exposes every registered resource as a tool via a single MCP endpoint — connect once, invoke anything.

Endpoint: https://hub.agent3.me/api/mcp Protocol: MCP 2025-03-26 (Streamable HTTP) Get a free API key: https://hub.agent3.me/auth/signup

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Setup#

Claude Desktop / any MCP client#

Add to your claude_desktop_config.json:

json

{
  "mcpServers": {
    "agent3": {
      "command": "npx",
      "args": ["-y", "mcp-remote", "https://hub.agent3.me/api/mcp"],
      "env": {
        "AGENT3_API_KEY": "a2a_your_key_here"
      }
    }
  }
}

Direct HTTP (curl)#

bash

curl -X POST https://hub.agent3.me/api/mcp \
  -H "Authorization: Bearer $AGENT3_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "resources_search",
      "arguments": { "query": "telegram search" }
    }
  }'

Anthropic SDK (Python)#

python

import anthropic

client = anthropic.Anthropic()

response = client.beta.messages.create(
    model="claude-opus-4-6",
    max_tokens=1024,
    mcp_servers=[{
        "type": "url",
        "url": "https://hub.agent3.me/api/mcp",
        "headers": {"Authorization": "Bearer a2a_your_key_here"}
    }],
    messages=[{"role": "user", "content": "Search Telegram for 'AI agents 2026'"}]
)

---

Available Tools#

ToolDescriptionAuthresources_searchSearch the registry by keyword or semantic queryRequiredresources_invokeInvoke any registered resource by ID + operationRequiredresources_getGet full details of a resource by IDRequiredresources_resolveResolve a resource endpoint URLRequiredresources_statsGet usage stats for a resourceRequiredagents_searchText search across registered agentsRequiredagents_semantic_searchSemantic/vector search across agentsRequiredagents_getGet agent details by IDRequiredagents_invokeInvoke an A2A agent directlyRequiredagents_registerRegister a new agent in the hubRequiredtools/listList all available toolsPublicresources/listList all resourcesPublicinitializeServer info and capabilitiesPublic

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Example: Search Telegram Content#

bash

curl -X POST https://hub.agent3.me/api/mcp \
  -H "Authorization: Bearer $AGENT3_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "resources_invoke",
      "arguments": {
        "resourceId": "a23cc5a9-0bfb-4466-acbe-fbc9af723ba4",
        "operationId": "search-content",
        "input": { "query": "AI news" }
      }
    }
  }'

Example: Search Google#

bash

curl -X POST https://hub.agent3.me/api/mcp \
  -H "Authorization: Bearer $AGENT3_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 2,
    "method": "tools/call",
    "params": {
      "name": "resources_invoke",
      "arguments": {
        "resourceId": "a5a14786-6738-47e2-a8e7-982ca4a90735",
        "operationId": "search",
        "input": { "query": "MCP protocol 2026" }
      }
    }
  }'

---

Rate Limits (Free Tier)#

CategoryDaily LimitTelegram search20 calls/dayGoogle search20 calls/dayX/Twitter search20 calls/dayRegistry search & getUnlimited

Limits reset at midnight UTC. Upgrade available at hub.agent3.me.

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Resource Types#

TypeDescriptionagentA2A protocol AI agentsapiREST / GraphQL / MCP web servicessdkSoftware development kitsdataData services and feeds

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Links#

• Registry: https://hub.agent3.me
• Docs: https://hub.agent3.me/docs
• Get API key: https://hub.agent3.me/auth/signup
• MCP endpoint: https://hub.agent3.me/api/mcp