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

Annotations already declare readOnlyHint and non-destructive, so safety is covered; the description adds the useful behavioral point that results are the user's own logged data, newest first, with a stated unit (lb). It doesn't cover empty-result behavior, so not a 5.

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?

Two sentences, both front-loaded with the return shape first and the call condition second. No redundant restatement of the tool name or schema.

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?

With no output schema, the description compensates by naming the returned fields and ordering. Minor gaps remain: behavior when an exercise has no logged sets, and whether results are truncated.

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 100% with the 1–20 id bound already documented, so the baseline is 3. The description adds genuine value by saying where the ids should come from (get_exercise_library or get_workout_history), which the schema does not convey.

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?

States a specific retrieval: the user's last logged sets with weight in lb, reps, and RPE, ordered newest first, for given exercises. That is concrete enough to distinguish it from get_personal_records or get_workout_history, though it does not explicitly contrast itself with those siblings.

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?

"Before suggesting loads" gives an explicit usage context, and it names the two sibling tools that supply the required exercise ids, establishing a dependency order. It lacks an explicit when-not-to-use clause, keeping it just 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.