# Solve complex

For teams past the basics who need sharper control.

- [Approval matrix](https://help.cortena.ai/guides/workflows/approval-matrix): Amount tiers, cost centers, and multi-step approvals.
- [Matching correction (quorum, verification & majority fill)](https://help.cortena.ai/guides/invoices/matching-correction): How Cortena resolves uncertain booking accounts: quorum matching, verification agent, then largest-value majority fill.
- [Multi-entity workflows](https://help.cortena.ai/guides/workflows/multi-entity-workflows): Route work across tenants and groups.
- [MCP server](https://help.cortena.ai/guides/advanced/mcp-server): Ask Cortena from ChatGPT or Claude via MCP.
- [Embat treasury](https://help.cortena.ai/guides/integrations/embat-treasury): Send approved invoices to Embat treasury.