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

Annotations already indicate readOnlyHint=false, so the create/mutating nature is expected. The description adds the row source and the 10,000-row limit, but does not disclose other behavioral details such as whether the dataset is linked to a report, how duplicates are handled, auth requirements, or effects on existing data. It does not contradict the annotations.

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 a single, well-structured sentence that front-loads the primary action and object, and includes a relevant constraint in parentheses. Every word adds value and there is no redundancy.

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?

Given that all parameters are fully described in the schema and an output schema exists, the description is sufficient for an agent to understand the tool's core purpose and input format. A brief note on when this dataset creation is needed relative to other custom-data operations would make it fully complete.

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 applies. The description mentions 'parsed CSV rows' which helps contextualize raw_data and columns, but it does not add meaningful parameter information beyond the schema's own descriptions. No additional semantics are provided.

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 action ('Create') and a specific resource ('custom-data dataset'), and adds the distinguishing source ('parsed CSV rows, max 10,000'). It clearly communicates what the tool does, though it does not explicitly compare itself to sibling tools such as create_asset or add_custom_data_widget.

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 implies when to use the tool: when a custom dataset needs to be created from already-parsed CSV rows. However, it does not mention any exclusions, prerequisites, alternatives, or why one would choose this over related create operations, so usage guidance is only implicit.

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