sqlike: MCP server & CLI

The deterministic safety net for SQL — for the code you write and the code your AI writes.

Your AI wrote a SQL query, or refactored one. Is it correct? Does it still return the same results? sqlike answers that — deterministically, in about a millisecond, and without your real data ever leaving your machine. Part of sqlike.

These are thin remote clients: an MCP server, a CLI, and a shared client library. They tokenize your SQL locally — identifiers and literals are masked before anything leaves your machine — and forward only the tokenized query to the sqlike API. There is no analysis engine here; that runs server-side and is closed.

Why

59% of developers ship AI-generated code they don't fully understand, and AI SQL looks plausible while being wrong more often than you'd like — a LEFT JOIN quietly becomes an INNER and drops rows, a WHERE goes missing and updates everything, tables get joined the wrong way. Plausible is not correct.

sqlike is the deterministic check that catches it — a guardrail, not another prompt. It verifies whether a rewrite really preserves results and flags unsafe patterns, and it never rubber-stamps a change that isn't safe: when it can't prove equivalence, it says Undecided rather than guess. No model in the loop means no retry loops, no per-token cost, and the same answer every time.

Install the MCP server

Add it to any MCP client (Claude Desktop, Cursor, etc.):

{
  "mcpServers": {
    "sqlike": { "command": "npx", "args": ["-y", "@sqlike/mcp"] }
  }
}

Or install via Smithery. An optional SQLIKE_API_KEY environment variable raises rate limits; without it you get the open anonymous tier.

Tools

analyze

Static analysis of one SQL query: validity, anti-patterns, suggested rewrites, and schema/index advice. Returns the JSON analysis envelope.

diff

Check whether two SQL queries are equivalent (result-preserving) — for verifying a rewrite or refactor, a judgement an LLM cannot reliably self-grade. Returns a verdict (Equivalent / EquivalentWithNotes / Differs / Undecided), a confidence level, and a per-property report (columns, rows, cardinality, order), so you see what changed, not just a yes/no. Undecided never means equivalent.

... View full README on GitHub