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

Annotations already declare destructiveHint=true and readOnlyHint=false, and the description adds valuable behavioral context beyond those flags: the values given become the entire table, so the caller must send the complete table. This clarifies the exact nature of the destructive replacement, which is useful for an agent making the call.

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?

The description is two sentences with no filler. The core action and the critical data-completeness warning are front-loaded, and the sibling alternative is stated concisely. Every sentence earns its place.

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?

The description covers the operation's destructive replacement behavior and the key alternative tool. With no output schema, return-value explanation is not required. It doesn't mention prerequisites like the dataset needing to exist, but that is reasonably implied by 'Replace an existing dataset'. Overall, it is complete enough for an agent to call the tool correctly.

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% (only dataset is described in the schema). The description compensates by clarifying the dataset parameter's role: it carries the new name and the full table of values. It also reinforces that values are data rows only. However, projectId and datasetId are not given additional meaning, so the compensation is incomplete but still strong.

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: 'Replace an existing dataset's name and values'. It also explicitly distinguishes itself from append_dataset_rows by telling the agent to call that sibling when adding rows, so the purpose is unambiguous and well differentiated.

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?

The description explicitly states the condition for using this tool ('replace an existing dataset's name and values') and provides a clear alternative for a different case ('To add rows, call append_dataset_rows instead'). This gives the agent direct routing guidance without ambiguity.

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