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

Beyond the readOnly and idempotent annotations, the description discloses the exact transformation: every row and column is kept, only the header changes, and unmapped columns become snake_case custom variables. It also explains the return behavior, including that the converted CSV is returned only when the input is 500 rows or fewer.

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 front-loaded, with the core transformation in the first sentence and behavioral details following efficiently. Every sentence adds useful information without repetition.

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 carries the return-value explanation itself and does so clearly: it returns the mapping plus the converted CSV when the threshold is met. Combined with the annotations and fully described input schema, this is complete enough for an agent to select and invoke 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 100%, so the two parameters are already well documented in the schema. The description reinforces the platform options and the CSV shape but does not add syntax or format details beyond the structured fields.

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: renaming a lead CSV's columns to sequencer import fields. It names concrete target platforms and clarifies that only headers change, which distinguishes it from siblings like clean_csv or combine_csvs.

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 usage context is clear: prepare a lead CSV for import into Instantly, Smartlead, EmailBison, or a generic snake_case format. It does not explicitly name when to choose this over clean_csv or combine_csvs, so it lacks full alternative routing guidance.

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