Read several ranges

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds real behavior beyond that: results are truncated per range to a share of max_cells, and a next_range token exists as a continuation mechanism. It doesn't describe permission requirements or the exact response shape, but the truncation/continuation disclosure is substantive.

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?

Three tight sentences: capability first, sibling comparison second, the non-obvious truncation/continuation behavior last. Every sentence carries distinct information with no repetition of schema content.

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 tool with no output schema, the description covers the important non-obvious return behavior (per-range truncation and the next_range continuation token), which is exactly what an agent needs to avoid mis-handling partial results. It could say more about the returned structure per range, but the critical gap is addressed.

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 80%, so the baseline is already 3. The description goes further by explaining how max_cells is allocated ('truncated to its share of max_cells'), which clarifies a parameter the schema only labels as a total. That added semantics lifts it above baseline.

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 several ranges in one call, across any tabs') and immediately differentiates itself from the sibling read_range by framing batched reads as the point. An agent can tell why this exists versus read_range without opening either schema.

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?

Explicitly positions itself against the alternative ('Faster than calling read_range repeatedly') and names the continuation path ('use its next_range with read_range to continue'), which tells the agent when to stay and when to follow up. It stops short of stating when NOT to use it (e.g. a single range), but the routing context is clear.

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