postgres-mcp-server

begin_transaction

Start a new database transaction to enable atomic execution of multiple SQL statements. Returns a transaction ID for subsequent operations.

Instructions

Start a new database transaction. Returns a transactionId to use with execute_sql, commit_transaction, or rollback_transaction. Transactions allow atomic execution of multiple statements.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

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

Input Schema

Name	Required	Description	Default
`name`	No	Optional human-readable name for the transaction to help identify it later

Schema Changelog

Changes observed during successful MCP inspections.

First observedv3.0.3May 30, 2026

TDQS

A4/5.0

Behavior3/5

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

With no annotations, the description adds minimal behavioral context beyond the basic function. It does not disclose potential side effects like lock acquisition or transaction timeout, which could affect agent decision-making.

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?

Two sentences that are front-loaded with the primary action and immediately useful. No unnecessary words.

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

Completeness4/5

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

Given the tool's simplicity (one optional parameter, no output schema), the description covers the essentials: action, return value, and related tools. A mention of the scope or implications of a transaction would improve completeness.

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% for the single optional parameter, and the description does not add further meaning beyond the schema. Baseline score of 3 is appropriate.

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

Purpose5/5

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

The description clearly states 'Start a new database transaction' and specifies the return value and associated tools. It distinguishes itself from sibling transaction tools like commit_transaction and rollback_transaction.

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

Usage Guidelines4/5

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

The description indicates usage with execute_sql, commit_transaction, and rollback_transaction, and mentions atomic execution. However, it lacks explicit guidance on when not to use or alternatives beyond the transaction lifecycle.

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