PostgreSQL MCP Server

pg_copy_between_databases

Copy data between two PostgreSQL databases by specifying source and target connection strings and table name. Supports conditional filtering and target table truncation options.

Instructions

Copy data between two databases

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": {
      "sourceConnectionString": "<sourceConnectionString>",
      "targetConnectionString": "<targetConnectionString>",
      "tableName": "<tableName>"
    },
    "name": "pg_copy_between_databases"
  }
}

Input Schema

Name	Required	Description	Default
`sourceConnectionString`	Yes
`targetConnectionString`	Yes
`tableName`	Yes
`where`	No
`truncateTarget`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedAug 15, 2025

TDQS

C2.8/5.0

Behavior2/5

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. 'Copy data between two databases' implies a write operation to the target database, but it doesn't disclose critical traits like whether this requires specific permissions, if it's a bulk operation, what happens on failure, or if there are rate limits. For a tool with 5 parameters and no annotation coverage, this is a significant gap in transparency.

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

Conciseness5/5

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

The description is a single, efficient sentence with zero waste. It's appropriately sized for the tool's name and gets straight to the point without unnecessary elaboration. Every word earns its place in conveying the core functionality.

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

Completeness2/5

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

Given the complexity (5 parameters, no annotations, no output schema, and 0% schema coverage), the description is inadequate. It doesn't explain what the tool returns, how parameters interact, or the operational context. For a data copying tool with multiple configuration options, more completeness is needed to guide effective use.

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

Parameters2/5

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

Schema description coverage is 0%, meaning none of the 5 parameters have descriptions in the schema. The tool description doesn't mention any parameters or provide meaning beyond the basic action. It fails to compensate for the lack of schema documentation, leaving parameters like 'where' and 'truncateTarget' completely unexplained in context.

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?

The description 'Copy data between two databases' clearly states the verb (copy) and resource (data between databases). It's specific about the action but doesn't differentiate from sibling tools like pg_export_table_data or pg_import_table_data, which might handle similar data movement operations. The purpose is unambiguous but lacks sibling distinction.

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?

The description provides no guidance on when to use this tool versus alternatives. With siblings like pg_export_table_data and pg_import_table_data that might handle similar data transfer tasks, there's no indication of when this tool is preferred or what specific scenarios it addresses. No exclusions or prerequisites are mentioned.

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

Deploy Server