set_item_fade_in

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

The annotations only include destructiveHint=false, so the description must carry behavioral disclosure. It states that it sets the length but does not mention whether existing fades are overwritten, if the change is reversible, or any side effects. No additional behavioral context is provided.

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 brief and front-loaded with the core purpose. The Args section is clear. It wastes no words, though it could benefit from a sentence clarifying the indices. It is appropriately concise for a simple setter.

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 tool with three required parameters and no output schema, the description is incomplete. It does not explain how to obtain track_index and item_index, any constraints (e.g., ranges, zero-based indexing), or what happens on success/failure. The description is too sparse to fully guide correct invocation.

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?

The schema has zero description coverage, so the description must explain all parameters. It only explains 'length' (fade-in length in seconds), leaving 'track_index' and 'item_index' completely undocumented. This is a partial compensation at best.

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 action: 'Set the fade-in length of a media item.' The verb 'Set' and resource 'fade-in length' are specific, and the sibling set_item_fade_out makes the distinction obvious without needing explicit contrast. The purpose is unambiguous.

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?

No guidance is given about when to use this tool vs alternatives, nor any prerequisites or context (e.g., how to identify the item, whether indices are zero-based, or when a fade-in would be applicable). The name alone implies the use case, but the description offers no explicit usage direction.

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