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

Annotations already declare destructiveHint=true, idempotentHint=false, so the safety profile is covered; the description adds that only *owned* comments can be touched (a permission constraint not in annotations) and that comments do not alter musical content, bounding the blast radius. It still does not say what is lost when action=delete or that a new annotation_id is returned on add.

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?

Three sentences, front-loaded with the action verbs before the parameter guidance, with little waste. 'A time_range, when provided, must be valid' is nearly tautological and is the weakest line.

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?

This is a destructive, non-idempotent write with a nested time_range object and no output schema, so the agent needs to know what a successful add returns (a new annotation_id) and which of the four required params apply per action (e.g. text on delete). Neither is covered, leaving real gaps for a mutation 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?

With 0% schema coverage across 7 parameters, the description carries the full burden and does document action's enum values, annotation_id's role for existing comments, time_range's presence constraint, and the note-selection/revision pairing. It leaves text and score_id implicit and gives no format detail for time_range ('must be valid' is vague), so it is strong but not complete.

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 names concrete verbs (store, edit, reply to, delete) and a precise resource (an owned score comment tied to exact note selection and revision). The final clause, 'Comments do not apply musical edits,' separates it from edit_score/revise_score siblings that mutate the score itself.

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?

It spells out the four action values (add, edit, reply, delete) and the condition that routes to existing comments ('existing comments use annotation_id'), which is actionable routing for the main decision. It does not name any sibling alternative to use instead of this tool, so it stops short of a 5.

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