music_cancel_change_plan

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

The annotation readOnlyHint: false already indicates a write operation, and destructiveHint: false indicates non-destructive. The description adds context that this cancellation does not alter the music itself, which is helpful. However, it does not disclose other side effects, such as whether the plan is permanently discarded or if there are any prerequisites.

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, tightly worded sentence that leads with the verb 'Cancel' and immediately clarifies the non-impact on Music. Every word adds value, and there is no superfluous information.

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 one-parameter cancellation operation, the description is sufficient in conjunction with the output schema and annotations. However, it does not address edge cases such as whether the plan must be in a 'pending' state or what happens if the plan is not found. Also, no mention is made of how this tool relates to sibling cancellation/undo operations, leaving the agent to infer usage from the name.

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 only one parameter (plan_id) with no description, and the tool description also says nothing about it. Since schema coverage is 0%, the description must compensate, but it does not add any explanation of what plan_id refers to or how to obtain it. The parameter name is somewhat self-explanatory, but the lack of explicit semantics is a gap.

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 ('Cancel') and the resource ('a pending plan'), and adds the qualifier 'without changing Music' to clarify the scope. It is unambiguous, though it does not explicitly distinguish itself from sibling tools like music_plan_undo.

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 intended use is implied: use when you need to cancel a pending plan while leaving the music library unchanged. However, no explicit guidance is given about when not to use it or how it compares to alternatives such as music_plan_undo, which might be appropriate for undoing applied changes.

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