Read a permission matrix

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

No annotations are provided, so the description carries the burden of behavioral disclosure. It explicitly discloses a non-obvious performance behavior: 'maxRows/offset/filter/columns are applied AFTER the full sheet is fetched.' This adds significant context beyond the schema and helps the agent anticipate resource usage.

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, both essential. The first states the core purpose; the second provides crucial behavioral guidance. No filler or redundancy. The most important caveat is front-loaded in the second 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 tool with 9 parameters and no output schema, the description covers the core purpose, return shape (structured records with header row keys), and the most impactful performance caveat. It could mention explicit return field structure or error cases, but the essential context for correct invocation is present.

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 baseline is 3. The description adds value by explaining how the key parameters interact: 'maxRows/offset/filter/columns are applied AFTER the full sheet is fetched.' This synthesizes the individual parameter descriptions and reveals the ordering semantics, which is not immediately obvious from the schema alone.

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 uses a specific verb+resource: 'Read a worksheet as structured records, using the header row as keys.' This distinguishes it from siblings like get_cell_range (raw cells) and describe_sheet (structure) by emphasizing structured row/record output.

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 provides clear usage guidance on handling truncation: 'If the result is truncated, narrow it with `filter` or `columns` first, and only page with `offset` as a fallback.' This tells the agent how to use the tool effectively in a common scenario, though it does not explicitly mention when to use this tool over siblings.

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