"Sanity" matching MCP servers:

Deterministic JSON validation and repair for AI agents. Validates, repairs, schema-checks, and diffs JSON so long-running agents don't corrupt their session state with malformed writes.

Enables evaluation of digital marketplaces by classifying demand signals, scoring commercial viability, sanity-checking claims, and comparing candidate channels.

Screens the counterparty of an x402 payment before an agent pays it. One tool, screen_payment, checks address sanity, dynamic-payTo swaps, transport safety and your spend policy, then returns allow / review / block with the reasons — advisory only, and by default it runs with no key, no account and no network call.

MCP server for discovering, triaging, and monitoring arXiv papers with transparent interest modeling and inspectable ranking.

Fans out queries to multiple independent free LLMs from different providers and returns their answers side by side, enabling sanity-checking of decisions or getting multiple perspectives during coding sessions.

Enables LLM agents to safely query educational administration databases through read-only MCP tools, enforcing SQL whitelisting, automatic LIMIT caps, parameterized queries, timeouts, token authentication, and audit logging.

Enables e-commerce customer service agents to retrieve product catalog and return/delivery policy documents through multi-source RAG with RRF fusion, exposing product_search and policy_qa tools for grounded, cited responses.

Enables natural-language querying of PostgreSQL databases with schema grounding and self-correcting error recovery. Provides a live audit trace and verifies results through exploratory decomposition and empty-result sanity checks.