Read-only-by-default MCP server for PostgreSQL. Query, introspect schemas, explain plans, health checks.
概览
One click adds this to your local Yaw MCP config so it's available in every Yaw Terminal session. Or install manually below. Read-only by default - writes opt in via a single env var - so an agent can't silently drop your tables. An index advisor, opt-in audit logging, structured tool output, and support for current-revision MCP clients. Full detail in the CHANGELOG. - recommends indexes for a workload and keeps only the ones that measurably lower estimated cost. Candidates are costed with HypoPG hypothetical indexes, never created on disk, and the search knows that PostgreSQL 18's skip scan changes which multi-column indexes are useful. - of the SQL tools send: one JSON line per audited statement, to stderr or a file. Bound parameter values are never recorded. Off by default, and not a complete record -- see Audit logging. - Every tool declares an outputSchema and returns structuredContent alongside the unchanged text block, so anything reading the text today keeps working.
README
以下为原文 README 节选，完整内容请查看原文。
@yawlabs/postgres-mcp
One click adds this to your local Yaw MCP config so it’s available in every Yaw Terminal session. Or install manually below.
Query a PostgreSQL database from Claude Code, Cursor, and any MCP client. Read-only by default - writes opt in via a single env var - so an agent can’t silently drop your tables.
Built and maintained by Yaw Labs.
What’s new in 0.12
An index advisor, opt-in audit logging, structured tool output, and support for current-revision MCP clients. Full detail in the CHANGELOG.
pg_index_advisorrecommends indexes for a workload and keeps only the ones that measurably lower estimated cost. Candidates are costed with HypoPG hypothetical indexes, never created on disk, and the search knows that PostgreSQL 18’s skip scan changes which multi-column indexes are useful.- Opt-in audit logging of the SQL tools send: one JSON line per audited statement, to stderr or a file. Bound parameter values are never recorded. Off by default, and not a complete record – see Audit logging.
- Structured tool output. Every tool declares an
outputSchemaand returnsstructuredContentalongside the unchanged text block, so anything reading the text today keeps working. - Both MCP protocol eras. The server used to speak only the legacy (2025) protocol revisions, which a client on the current 2026-07-28 revision fails against. It now serves both.
On 0.12.0? Upgrade. 0.12.1 closes a stacked-query hole in pg_index_advisor: SQL passed in its statements argument ran on a protocol that accepts several commands in one string, so SELECT 1; COMMIT; DROP SCHEMA public CASCADE; escaped the read-only transaction. The tool is annotated read-only, so hosts often auto-allow it. The same release stops pg_inspect_locks attributing a lock held in another database to whichever local table shares its OID, fixes the advisor’s greedy search, and makes audit lines carry the tool field they were missing.
Coming from 0.10.x? 0.11.0 has three breaking changes: pg_seq_scan_tables, pg_unused_indexes and pg_top_queries return an envelope (read data.rows where you used to read data), pg_explain with analyze: true emits BUFFERS (pass buffers: false for the old output), and Node 22 is the floor. Details in the 0.11.0 changelog entry.
Backstory
安装
npx -y @yawlabs/postgres-mcp@latest配置
{
"mcpServers": {
"postgres": {
"command": "npx",
"args": ["-y", "@yawlabs/postgres-mcp@latest"],
"env": {
"DATABASE_URL": "postgres://user:password@host:5432/dbname"
}
}
}
}