Cerbos MCP Server for LlamaIndexGive LlamaIndex instant access to 6 tools to Authzen Evaluation, Authzen Evaluations, Check Resources, and more
LlamaIndex specializes in data-aware AI agents that connect LLMs to structured and unstructured sources. Add Cerbos as an MCP tool provider through Vinkius and your agents can query, analyze, and act on live data alongside your existing indexes.
Ask AI about this MCP Server for LlamaIndex
The Cerbos MCP Server for LlamaIndex is a standout in the Developer Tools category — giving your AI agent 6 tools to work with, ready to go from day one.
Vinkius delivers Streamable HTTP and SSE to any MCP client
import asyncio
from llama_index.tools.mcp import BasicMCPClient, McpToolSpec
from llama_index.core.agent.workflow import FunctionAgent
from llama_index.llms.openai import OpenAI
async def main():
# Your Vinkius token. get it at cloud.vinkius.com
mcp_client = BasicMCPClient("https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp")
mcp_tool_spec = McpToolSpec(client=mcp_client)
tools = await mcp_tool_spec.to_tool_list_async()
agent = FunctionAgent(
tools=tools,
llm=OpenAI(model="gpt-4o"),
system_prompt=(
"You are an assistant with access to Cerbos. "
"You have 6 tools available."
),
)
response = await agent.run(
"What tools are available in Cerbos?"
)
print(response)
asyncio.run(main())
* Every MCP server runs on Vinkius-managed infrastructure inside AWS - a purpose-built runtime with per-request V8 isolates, Ed25519 signed audit chains, and sub-40ms cold starts optimized for native MCP execution. See our infrastructure
About Cerbos MCP Server
Connect your Cerbos instance to any AI agent to manage complex authorization policies through natural language conversation.
LlamaIndex agents combine Cerbos tool responses with indexed documents for comprehensive, grounded answers. Connect 6 tools through Vinkius and query live data alongside vector stores and SQL databases in a single turn. ideal for hybrid search, data enrichment, and analytical workflows.
What you can do
- Permission Evaluation — Use
check_resourcesto instantly verify if a principal can perform specific actions on resources based on your policies. - Query Planning — Generate AST-based query plans with
plan_resourcesto filter database results according to user permissions. - AuthZEN Compliance — Leverage standardized access requests using
authzen_evaluationandauthzen_evaluationstools. - System Monitoring — Check instance health and build metadata using
get_server_infoandget_authzen_config.
The Cerbos MCP Server exposes 6 tools through the Vinkius. Connect it to LlamaIndex in under two minutes — credentials fully managed, no infrastructure to provision, no vendor lock-in. Your configuration, your data, your control.
All 6 Cerbos tools available for LlamaIndex
When LlamaIndex connects to Cerbos through Vinkius, your AI agent gets direct access to every tool listed below — spanning authorization, rbac, abac, and more. Every call runs in a secure, isolated environment with full audit visibility. Beyond a simple connection, you get real-time monitoring of agent activity, enterprise governance, and optimized token usage.
Authzen evaluation on Cerbos
Single action evaluation using the AuthZEN entity model
Authzen evaluations on Cerbos
Supports execute_all, deny_on_first_deny, and permit_on_first_permit semantics. Batch evaluation of multiple access requests using AuthZEN
Check resources on Cerbos
This is a read-only evaluation. Evaluates permissions for a principal on a set of resources
Get authzen config on Cerbos
Returns endpoint URLs for the AuthZEN APIs
Get server info on Cerbos
Returns the version and build details of the Cerbos instance
Plan resources on Cerbos
Produces a query plan for obtaining a list of resources a principal is allowed to access
Connect Cerbos to LlamaIndex via MCP
Follow these steps to wire Cerbos into LlamaIndex. The entire setup takes under two minutes — your credentials stay safe behind Vinkius.
Install dependencies
pip install llama-index-tools-mcp llama-index-llms-openaiReplace the token
[YOUR_TOKEN_HERE] with your Vinkius tokenRun the agent
agent.py and run: python agent.pyExplore tools
Why Use LlamaIndex with the Cerbos MCP Server
LlamaIndex provides unique advantages when paired with Cerbos through the Model Context Protocol.
Data-first architecture: LlamaIndex agents combine Cerbos tool responses with indexed documents for comprehensive, grounded answers
Query pipeline framework lets you chain Cerbos tool calls with transformations, filters, and re-rankers in a typed pipeline
Multi-source reasoning: agents can query Cerbos, a vector store, and a SQL database in a single turn and synthesize results
Observability integrations show exactly what Cerbos tools were called, what data was returned, and how it influenced the final answer
Cerbos + LlamaIndex Use Cases
Practical scenarios where LlamaIndex combined with the Cerbos MCP Server delivers measurable value.
Hybrid search: combine Cerbos real-time data with embedded document indexes for answers that are both current and comprehensive
Data enrichment: query Cerbos to augment indexed data with live information before generating user-facing responses
Knowledge base agents: build agents that maintain and update knowledge bases by periodically querying Cerbos for fresh data
Analytical workflows: chain Cerbos queries with LlamaIndex's data connectors to build multi-source analytical reports
Example Prompts for Cerbos in LlamaIndex
Ready-to-use prompts you can give your LlamaIndex agent to start working with Cerbos immediately.
"Check if principal 'user_123' with role 'editor' can 'edit' resource 'document:abc'."
"Generate a query plan for 'view' action on 'expense' resources for principal 'manager'."
"Show me the Cerbos server build details."
Troubleshooting Cerbos MCP Server with LlamaIndex
Common issues when connecting Cerbos to LlamaIndex through Vinkius, and how to resolve them.
BasicMCPClient not found
pip install llama-index-tools-mcpCerbos + LlamaIndex FAQ
Common questions about integrating Cerbos MCP Server with LlamaIndex.
How does LlamaIndex connect to MCP servers?
Can I combine MCP tools with vector stores?
Does LlamaIndex support async MCP calls?
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