Recent strength sessions

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

Beyond the readOnly/idempotent/openWorld annotations, it discloses request cost ('one Garmin request per session plus one, and one more the first time in a process'), failure semantics ('a session whose sets cannot be read carries sets_error'), and rate-limit behavior ('a rate limit stops the call'). These are exactly the operational traits an agent cannot infer from structured fields.

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?

Front-loaded with what the tool returns, then routing guidance, then operational caveats. Every sentence carries non-redundant information (sibling routing, set_number caveat, request budget, error field) with no filler.

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?

An output schema exists, so return-shape explanation is not required, yet the description still flags the sets_error case. Combined with explicit routing to list_activities and get_activity_sets/edit_activity_sets, an agent has everything needed to select and call this tool correctly.

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 100%, so the schema already documents count and include_sets, establishing a baseline of 3. The description reinforces the cost implication of include_sets via the per-session request count, but adds no syntax, default, or format detail beyond what the schema states.

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 verb (List) and resource (recent completed strength sessions) with scope and ordering ('newest first') and enumerates the payload ('exercises, reps and weights and its total volume'). It clearly differentiates itself from list_activities and get_activity_sets, which an agent could otherwise confuse with this aggregated tool.

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 names the alternative explicitly ('One call instead of list_activities plus get_activity_sets per session'), states the exclusion ('It takes no dates: for a period, use list_activities with activity_type strength_training and start_date'), and warns about a downstream workflow prerequisite ('read a session with get_activity_sets before correcting it with edit_activity_sets'). Both when-to-use and when-not-to-use are covered.

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