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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds useful behavioral context beyond that: the database engine is Postgres and the result is metadata only, containing no rows. It says nothing about size limits, output ordering, or behavior for nonexistent ids.

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?

One short sentence with zero filler, and the key scope constraint ('no rows') is placed at the end where it stands out. It is a sentence fragment rather than a complete statement, which slightly hurts readability but not comprehension.

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 single-parameter read tool with no output schema, the description conveys the essential return shape: tables, their columns, names, and types, with no row data. Gaps such as whether views or indexes are included, or how a missing id is handled, are minor for a tool of this simplicity.

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%, and the single `id` parameter is already documented as coming from list_services. The description adds no meaning beyond the schema, so the baseline 3 applies.

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 names a specific resource (a Postgres database's tables and their columns) and specifies the returned details (names and types), which lets an agent distinguish it from run_sql or get_database_stats. The verb is implicit rather than stated, and no sibling is named explicitly, so it falls short of a 5.

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 phrase 'no rows' implicitly contrasts this with data-returning tools like run_sql, suggesting schema-inspection usage. However, there is no explicit when-to-use guidance, no statement of prerequisites, and no named alternative for retrieving actual data.

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