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 context that results are keyed by field name and that the limit is capped at 500, plus the SQL-over-tables note, but says nothing about pagination, defaults, or the workspace/auth requirement mentioned only in the schema.

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?

Two dense sentences, front-loaded with what is returned before the options and the alternative tool. Nothing is redundant, though the SQL aside is parenthetical and slightly compresses two distinct ideas into one sentence.

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 read-only query with no output schema, the description gives only a hint of the return shape ('keyed by field name') and does not explain pagination/offset behavior or result ordering. It is adequate for a basic fetch but leaves real gaps for a 9-parameter query tool.

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 only 33% across 9 parameters, so the description must carry weight. It names where, sort, search and limit (with the 500 cap) but adds no operator, format or default detail, and ignores offset, match and workspace entirely — the offset/pagination behavior in particular is undocumented anywhere in the description.

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?

States a specific verb and resource: it returns records from a table tab, keyed by field name, with named filter/sort options. It also carves out an adjacent use case (aggregation) for a sibling. It does not distinguish itself from close siblings like napkin_tables_get, so it stops 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?

It explicitly routes the agent elsewhere when the task is a count, sum or join, naming napkin_sheets_query and explaining that each table is an SQL table with an id column. That is a concrete alternative with a selecting condition, though it gives no explicit 'do not use this for X' for other siblings.

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