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Version: 1.0.0
MCP Server for Cronos Blockchain

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Overview

CATO (Cronos Agentic Tooling Orchestrator) is an MCP (Model Context Protocol) server that provides AI agents with comprehensive access to Cronos blockchain functionality, including:
  • Multi-chain portfolio aggregation (EVM, zkEVM, POS)
  • DeFi yield comparison across protocols
  • Transaction error debugging and analysis
  • SDK documentation and code examples
  • Smart contract templates with deployment scripts
  • Cross-chain bridge instructions
  • x402 gasless payment technology integration
Base URI: N/A (MCP server via stdio transport)
Protocol: Model Context Protocol (MCP) v1.0
License: MIT

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Quick Navigation

MCP Tools

7 powerful tools for blockchain interaction

MCP Resources

Access historical transaction data

Error Handling

Consistent error response format

Rate Limits

Understand usage limitations

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MCP Tools

CATO provides 7 core tools for interacting with the Cronos blockchain:

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Portfolio & Assets

get_unified_portfolio

Aggregate token balances across all Cronos chains (EVM, zkEVM, POS) for a given address.

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DeFi Analytics

find_best_yield

Compare yield opportunities across Cronos DeFi protocols (Tectonic, VVS Finance, Fulcrom).

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Developer Tools

decode_transaction_error

Decode revert reasons from failed transactions

query_cronos_sdk_docs

Search across all Cronos documentation

get_contract_template

Retrieve smart contract templates

get_bridge_instructions

Get cross-chain bridge guides

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Payment Technology

get_x402_examples

x402 payment technology documentation and code examples for gasless payments.

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MCP Resources

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Transaction History

cronos://history/{address}

Provides historical transaction data from BigQuery for a given Cronos address.

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Error Handling

All tools return errors in a consistent format: 
{
  "content": [
    {
      "type": "text",
      "text": "{\"error\": \"Error description\"}"
    }
  ],
  "isError": true
}

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Common Error Codes

ErrorDescriptionSolution
Invalid address formatAddress doesn’t match 0x… or cro1… patternVerify address format
Transaction not foundTX hash doesn’t exist on chainCheck hash and chain parameter
RPC timeoutChain query exceeded 5s timeoutRetry request
BigQuery auth failedMissing GCP credentialsRun gcloud auth application-default login
No results foundSearch query returned no matchesTry broader search terms

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Rate Limits

CATO uses public RPC endpoints with the following limits:
EndpointRate LimitTimeout
Cronos EVM RPC~50 req/sec30s
Cronos zkEVM RPC~50 req/sec30s
Cronos POS RPC~50 req/sec30s
BigQueryGCP quota60s
Recommendations:
  • Implement exponential backoff for retries
  • Cache responses when appropriate
  • Use portfolio aggregation instead of individual chain queries

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Tool Categories

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By Functionality

  • get_unified_portfolio - Multi-chain balance aggregation

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By Use Case

  1. Use query_cronos_sdk_docs to find SDK examples
  2. Get contract templates with get_contract_template
  3. Debug transactions using decode_transaction_error
  1. Check portfolio with get_unified_portfolio
  2. Find yield opportunities using find_best_yield
  3. Bridge assets with get_bridge_instructions
  1. Learn about x402 with get_x402_examples
  2. Get implementation guides
  3. Review code examples
  1. Decode errors with decode_transaction_error
  2. Check transaction history via resources
  3. Review gas analysis

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Example Usage

Here’s a typical workflow using CATO tools:

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Check Portfolio & Find Opportunities

# 1. Check user's portfolio
portfolio = use_mcp_tool(
    server_name="cato",
    tool_name="get_unified_portfolio",
    arguments={
        "address": "0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb0"
    }
)

# 2. Find yield opportunities for their USDC
yields = use_mcp_tool(
    server_name="cato",
    tool_name="find_best_yield",
    arguments={
        "token_symbol": "USDC",
        "min_risk_score": "LOW",
        "min_apy": 5
    }
)

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Debug & Fix Transactions

# 1. Decode transaction error
error = use_mcp_tool(
    server_name="cato",
    tool_name="decode_transaction_error",
    arguments={
        "tx_hash": "0xabc123...",
        "chain": "evm"
    }
)

# 2. Get documentation for proper implementation
docs = use_mcp_tool(
    server_name="cato",
    tool_name="query_cronos_sdk_docs",
    arguments={
        "query": "approve tokens",
        "language": "typescript"
    }
)

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Additional Resources

Cronos Documentation

Official Cronos documentation

MCP Protocol Spec

Learn about Model Context Protocol

GitHub Repository

View source code and contribute

Support

Get help from the community
Last Updated: January 23, 2026
API Version: 1.0.0