"Vector Database" matching MCP servers:

Lets Claude run a small online store's back office — searching customers, looking up and listing orders, generating sales reports and low-stock alerts, updating order status, issuing refunds, and creating invoices — with server-side guardrails like refund caps, idempotency keys, an order state machine, and audit logging on every write. Includes a deterministic eval harness that grades agent behaviour against the actual database state.

Enables coding agents such as Claude Code or Codex to run and stop the timer, log, correct, delete and restore time entries, read settings, projects, clients, tags, entries and reports, and preview invoices or create and edit invoice drafts. It communicates over stdin/stdout without opening a port, writes to the same audited database as the app, and leaves issuing or voiding invoices to the user in the app.

Thingery is the open item database and MCP server for AI agents to list, find, and trade second-hand goods. Agents publish listings with photos and category attributes, search via hybrid semantic/keyword filters, and connect to the hosted instance or self-host with Postgres + pgvector (npx thingery over stdio).

RailRouter Lite is a real, production-ready MCP server implementing the Model Context Protocol. It exposes one tool: route_payment. This tool intelligently routes payments to the optimal rail (Stripe MPP, Coinbase x402, or Google AP2) in real time, choosing based on cost, latency, and success rate. Every decision is logged to a Cloudflare D1 database, creating compounding routing intelligence

Enables an LLM to query and manage customers and invoices—listing clients, searching invoices by status, computing outstanding debt, creating invoices, and marking them paid—through a closed set of server-validated tools without direct database access. Business rules such as amount limits, accumulated daily caps, and input validation are enforced server-side to resist prompt injection and misuse.

Deploy and monetize agent-built apps from one MCP. Ship a full-stack app (login, database, usage billing) with one command, then charge the signed-in end user per API call via X-Settle-Payer (end-user-pays: cost times markup, app owner earns the markup).

Gives Claude read-only tools over hotel finance data — PMS statistics, POS takings and room charges, card settlements, bank exceptions, supplier invoices and ad spend — alongside write tools that require explicit human approval, such as posting a room charge to a folio or raising a balancing journal. Writes are guarded (balanced journals, real accounts, limits, no duplicates) and every tool call, approval and rejection is logged, letting finance staff investigate red checks and apply fixes without touching the database directly.

MCP server providing guarded access to a B2B SaaS billing database (customers, subscriptions, invoices, credit notes) and live ECB exchange rates, with read-only tools and one capped, idempotent write for issuing credit notes.

Enables AI assistants to handle payment support tasks by orchestrating between Stripe and an internal orders database, with human approval required for refunds.

PayDesk MCP is a production-grade Model Context Protocol (MCP) server that exposes payment gateway APIs, tools, prompts, and resources. It bridges the gap between an AI assistant and three underlying database systems to resemble real payment services like Stripe, Razorpay, or PayPal.