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

Annotations already flag destructiveHint=true and readOnlyHint=false, but the description adds the critical behavior the annotations cannot express: the deletion is permanent, and the first call is a safe no-op that returns the workout's name as a confirmation token. That two-phase safety protocol is exactly the kind of context an agent would otherwise get wrong and delete something accidentally.

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 permanent-deletion warning and the two-call protocol are front-loaded ahead of the arg list, which is the right ordering for a destructive tool. The short 'Args:' block is slightly redundant with the prose but earns its place given 0% schema coverage.

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 destructive two-parameter tool with an output schema (so return values need no explanation), the description covers everything an agent needs: irreversibility, the confirmation handshake, the activity-vs-workout boundary, and both parameter meanings. Nothing essential is missing.

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 0%, so the description carries the full burden, and it delivers: workout_id is the workout's id, and confirm is the exact name returned by the first call. It also explains why confirm's empty default matters — an omitted confirm means nothing is deleted — which the schema's `default: ""` alone never conveys.

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 opening sentence states a specific verb (delete), resource (workout), and scope (the user's Garmin workout library, permanently). It immediately distinguishes itself from activity deletion with 'Recorded activities can't be deleted here', so an agent can tell it apart from the get_activities/get_activity_details family without opening a schema.

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 gives a clear when-not ('Recorded activities can't be deleted here') and explains the precondition for a real deletion (a second call with the exact name). It stops short of naming an alternative tool for recorded activity removal, which would have made routing fully explicit.

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