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Agents & workflowsMCP serverModule

Postgres MCP, Read-Safe

What it’s for: Let an AI assistant query your database through a read-only role, plus the parts free Postgres MCP servers leave to you: per-role policies, column masking, an audit log and a red-team suite.

Sold by @halcyonDeclared by creator
Made withClaude Opus 5.5DeepSeek-V4-Pro

Code excerpt

const server = new McpServer({ name: 'postgres-read-safe', version: '1.3.0' });
 
server.tool('query', { sql: z.string(), limit: z.number().max(500) }, async ({ sql, limit }) => {
  if (!isReadOnly(sql)) {
    return { isError: true, content: [{ type: 'text', text: 'Only SELECT is allowed.' }] };
  }
  const rows = await pool.query(`${sql} LIMIT ${limit}`);
  return { content: [{ type: 'text', text: JSON.stringify(mask(rows.rows)) }] };
});
Partial code: 260 more lines in this file, full source after purchase.

Versions

Earlier versions sell at their own price.

Postgres MCP, Read-Safe

v1.3 · Use license

Dossier

What it is, how it was made, and what you need to run it.

Agents & workflows details

Compatible platforms
Any MCP-compatible client
Required permissions
A read-only database role you create, with one policy file per role
Estimated cost per run
Visible after purchase

Process notes

Approach
Made with Claude Opus 5.5 and DeepSeek-V4-Pro and run against the lab’s own databases before release. The red-team suite has 150 prompts that try SQL injection, schema probing and data exfiltration, and v1.3 passes all of them with the policies it ships.
Prompts and settings
Visible after purchase

What’s included

The exact contents you receive. Each file is listed with its size and fingerprint, so you can check that your copy is complete.

PathSizeSHA-256
  • README.md7.4 KBa1bae860
  • LICENSE.md1.7 KB201c7043
  • agent.yaml3.7 KBcf4a0ff7
  • charts/postgres-mcp/4.0 KB2 files
    • Chart.yaml689 Bdeb38911
    • values.yaml3.3 KB30e746bf
  • docs/4.8 KB1 file
    • deploy.md4.8 KBaf36b15b
  • evals/199 KB1 file
    • cases.jsonl199 KBbdb70388
  • policies/5.2 KB1 file
    • roles.example.yaml5.2 KBc15e6038
  • prompts/8.0 KB1 file
    • system.md8.0 KB14d30a53
  • redteam/79 KB1 file
    • prompts-150.jsonl79 KB1af414f0
  • tools/16 KB1 file
    • handlers.ts16 KBf4dffaab
11 files in 7 foldersTotal 329 KB

Text files and datasets in your copy carry your order’s marks, so their fingerprints differ from those shown here; your copy’s license file lists its exact fingerprints. Images, video and other binary files arrive unchanged.

License in plain words

For the Use license you have selected.

You can

  • Use the work in your own projects and in work you deliver to clients
  • Edit and adapt it to fit those projects
  • Use it commercially, for example in ads, products you sell or paid client work

You can’t

  • Resell, share or give away the work itself, even if you modified it
  • Ship it inside a product that other people download or resell as a template
  • Claim you created it or use it to train a competing AI model

Questions before you buy

Ask @halcyon anything about this work. Answers are public.

0/800

  • Sam L. · 11d

    Which permissions are actually required versus optional?

    Halcyon LabCreator · 10d

    Only the ones listed as required. Everything else can be switched off in the config.

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