Show one cell's formula and what it reads

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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false, so safety and repeatability are covered. The description adds real behavioral detail beyond that: it discloses the return contents (formula or value, cached result when present, and precedent cells), including the conditional "if the file has one" for stored results.

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 sentences, zero filler. The return contents are front-loaded and the second sentence earns its place by supplying the investigative use case.

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, the description correctly carries the burden of explaining what comes back, and it does so reasonably well. However, it omits error behavior for empty or missing cells and the meaning of path/sheet, so an agent still lacks enough to call it confidently in edge cases.

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 0%: path, sheet, and cell carry only types, and the description says nothing about any of them. The schema's regex hints that cell is an A1-style reference, but path (workbook file?) and sheet semantics are entirely undocumented in both places.

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 states a specific verb and resource: it returns the formula or value of one cell, its stored result, and the cells the formula reads. That distinguishes it clearly from audit_workbook in substance, though the sibling is never named or contrasted.

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?

"Use it to follow a suspicious number back to its inputs" gives a concrete use case, which is more than nothing. But there is no when-not guidance and no explicit routing between this cell-level inspection and the workbook-level audit_workbook sibling.

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