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

With no annotations, the description carries the full burden and does so: it discloses formula-vs-computed-value preference, that it returns structure/text rather than the file (with the size reason), and the permission model (setup sheets and import templates are admin/developer only; reports follow the caller's report permissions).

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?

Front-loaded with the core action and the sheet/no-sheet branching, and each sentence contributes distinct information (kinds, structure output, formula preference, non-file caveat, permissions). It runs a bit long but is dense rather than padded.

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?

With no output schema and no annotations, the description compensates fully: it describes what each mode returns (sheet extents, defined names with scope/target, cell contents with formulas), the paging model via schema, and the access constraints.

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 coverage is 100%, so the schema already documents all seven parameters including the sheet dual-mode, paging (fromRow/maxRows/maxCols), and defaults. The description restates the sheet behavior rather than adding new semantics, so 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?

States a specific verb and resource ('Read inside one workbook') and enumerates the three workbook kinds it covers. It distinguishes itself from siblings by naming list_database_sheets for discovery and contrasting its structural vs. cell-level modes.

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 clearly explains the two invocation modes ('Called without sheet... Called WITH sheet') and routes discovery to list_database_sheets. It also states an exclusion — use the admin's Download button if you want the actual file — though it doesn't contrast against report-data siblings like get_report_data.

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