# PostgreSQL_list_extensions

List all available PostgreSQL extensions (installed and available).

Agent View of the PolicyLayer registry record for `PostgreSQL_list_extensions`. HTML page: https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-list-extensions

## Facts

- Tool: `PostgreSQL_list_extensions`
- Server: Postgres (`mukul975/postgres-mcp-server`) — https://policylayer.com/tools/mukul975-postgres-mcp-server.md
- Homepage: https://github.com/mukul975/postgres-mcp-server
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Allowed

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "PostgreSQL_list_extensions",
    "arguments": {}
  }
}
```

## Why PostgreSQL_list_extensions is rated Low

The tool performs a read-only operation to enumerate installed and available PostgreSQL extensions. There are no side effects, no code execution, no data modification, and no destructive operations. The blast radius of misuse is minimal—an AI agent listing extensions cannot cause harm to data or systems. This is a straightforward information retrieval tool.

From the tool's own definition: "Tool name contains 'list' and description states 'List all available PostgreSQL extensions'. This is a query operation that retrieves information about extensions without modifying, executing, or deleting anything."

## Use case

AI agents call PostgreSQL_list_extensions to retrieve information from Postgres without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Postgres:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "PostgreSQL_list_extensions": {}
  }
}
```

## Other tools on Postgres (238)

- `PostgreSQL_drop_index` — Destructive — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-drop-index.md
- `PostgreSQL_drop_schema` — Destructive — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-drop-schema.md
- `PostgreSQL_drop_user` — Destructive — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-drop-user.md
- `PostgreSQL_analyze_database` — Execute — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-analyze-database.md
- `PostgreSQL_execute_select_query` — Execute — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-execute-select-query.md
- `PostgreSQL_execute_update_query` — Execute — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-execute-update-query.md
- `PostgreSQL_kill_connection` — Execute — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-kill-connection.md
- `PostgreSQL_refresh_materialized_view` — Execute — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-refresh-materialized-view.md
- `PostgreSQL_vacuum_analyze_table` — Execute — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-vacuum-analyze-table.md
- `analyze_buffer_utilization` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/analyze-buffer-utilization.md
- `analyze_foreign_key_locks` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/analyze-foreign-key-locks.md
- `analyze_index_effectiveness` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/analyze-index-effectiveness.md
- `analyze_query_complexity` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/analyze-query-complexity.md
- `analyze_query_plans` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/analyze-query-plans.md
- `analyze_sequence_usage` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/analyze-sequence-usage.md
- `analyze_transaction_wraparound` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/analyze-transaction-wraparound.md
- `analyze_trigger_performance` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/analyze-trigger-performance.md
- `analyze_vacuum_efficiency` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/analyze-vacuum-efficiency.md
- `check_constraint_violations` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/check-constraint-violations.md
- `check_database_encoding_collation` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/check-database-encoding-collation.md
- `check_function_performance` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/check-function-performance.md
- `check_replication_lag_details` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/check-replication-lag-details.md
- `check_table_inheritance` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/check-table-inheritance.md
- `monitor_autovacuum_progress` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/monitor-autovacuum-progress.md
- `monitor_checkpoint_efficiency` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/monitor-checkpoint-efficiency.md
- `monitor_connection_patterns` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/monitor-connection-patterns.md
- `monitor_materialized_views` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/monitor-materialized-views.md
- `monitor_wal_generation_rate` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/monitor-wal-generation-rate.md
- `PostgreSQL_active_temp_file_users` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-active-temp-file-users.md
- `PostgreSQL_analyze_advanced_buffer_usage` — Read — https://policylayer.com/tools/mukul975-postgres-mcp-server/postgresql-analyze-advanced-buffer-usage.md
- …and 208 more: https://policylayer.com/tools/mukul975-postgres-mcp-server.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=mukul975-postgres-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/mukul975-postgres-mcp-server