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

With no annotations, the description carries full burden. It details behavior: original trimmed, new region created, straddling notes kept. It does not mention undo or side effects, but the behavior is transparent enough for a split operation.

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 well-structured: purpose, behavior, use cases, parameter list, returns, example. Each section is concise and useful, no wasted sentences.

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 the output schema exists, no need to explain return values. The description covers all necessary aspects: behavior, use cases, parameters, and example, making it fully complete for a split tool.

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 0%, so description compensates fully. It explains all 4 parameters (unit_index, track_index, region_index, split_beat) with purpose and constraints (split_beat must be within region range), plus an example. Adds significant meaning.

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 clearly states the tool's action: split a note region into two at a given beat position. It explains the behavior (trim original, create new region, handle straddling notes) and distinguishes from sibling tools like merge or delete by the specific splitting action.

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 provides explicit use cases (e.g., divide long region, cut silence, create variations) and an example, guiding when to use. It lacks explicit when-not or alternative tools, but the context and use cases sufficiently indicate usage.

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