pg_upgrade

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively communicates that this is a 'potentially destructive operation' (mentioned in the input schema description for 'confirm' parameter) and that it includes 'confirmation protection' and 'manages safe database version upgrades.' This covers key behavioral aspects like safety mechanisms and destructive potential.

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

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

The description is efficiently structured with a clear opening statement followed by a bulleted list of use cases and a concluding sentence about safety features. Every sentence adds value, though the concluding sentence could be slightly more concise by integrating with the opening statement.

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

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

For a complex, potentially destructive database upgrade tool with no annotations and no output schema, the description provides good context about use cases and safety mechanisms. However, it doesn't mention what happens during the upgrade (downtime, backup requirements) or what the tool returns, leaving some gaps in completeness.

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

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

Schema description coverage is 100%, so the schema already documents all four parameters thoroughly. The description doesn't add any parameter-specific information beyond what's in the schema descriptions, so it meets the baseline of 3 where the schema does the heavy lifting for parameter documentation.

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

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

The description clearly states the specific action ('upgrade PostgreSQL database version') and resource ('PostgreSQL database'), distinguishing it from sibling tools like pg_backups, pg_info, or pg_maintenance which have different purposes. It goes beyond just restating the name by specifying the scope of the upgrade operation.

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

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

The description explicitly lists four specific use cases when to use this tool: 1) Migrate to newer version, 2) Plan upgrade paths, 3) Execute controlled migrations, and 4) Verify compatibility. This provides clear guidance on when this tool is appropriate versus alternatives like pg_maintenance or other database tools.

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