mcp-postgres

pg_enum_list

Retrieves all enum types and their values from a PostgreSQL database. Useful for inspecting custom enumerations in the schema.

Instructions

List all enum types and their values.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "target": "<target>"
    },
    "name": "pg_enum_list"
  }
}

Input Schema

Name	Required	Description	Default
`target`	Yes	Target name from ~/.dbx/targets/

Schema Changelog

Changes observed during successful MCP inspections.

First observedv2026.4.10-3Jul 25, 2026

TDQS

C2.9/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description must cover behavioral aspects. It only states the action without mentioning any side effects, permissions, or requirements (e.g., needing an active connection).

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Single sentence, front-loaded with the key action and resource. Concise but could potentially include a brief note about prerequisites like active connection.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool has one required parameter and no output schema, the description is minimally adequate. However, it lacks context about the current database context or connection state, which is important given sibling tools that require connections.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% (1 parameter with description). The description adds no additional meaning beyond what the schema already provides for the 'target' parameter. Baseline of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

Description clearly states 'List all enum types and their values', specifying the verb and resource. It distinguishes from sibling tools like pg_schema_list and pg_table_list by focusing specifically on enum types.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance on when to use this tool versus alternatives, such as requiring an active connection or being used after connecting to a database. No exclusions or preconditions mentioned.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.