Get recent activities

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful behavioral context: newest-first ordering, the specific metrics returned, and the fact that splits/laps are NOT included (delegated to get_activity_details). It does not mention pagination or the default/cap on limit, but the schema already documents those. The description adds value beyond annotations without contradicting them.

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, each earning its place: the first states the core function and output fields, the second covers filtering, and the third routes to the sibling for more detail. The most important information (what it lists and how it's ordered) is front-loaded. No filler or repetition of schema details.

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 read-only list tool with 100% schema coverage and no output schema, the description is nearly complete. It covers what is returned, the ordering, and the filtering options, and it points to the sibling for deeper detail. The only minor gap is that it doesn't explicitly state the default limit of 10 or the 100 cap, but those are already in the schema, so the description need not repeat them. The openWorldHint annotation also signals that the list may not be exhaustive, which is useful context.

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 all four parameters (after, before, limit, sport_type) with types and examples. The description adds the filter concept ('Filter by sport type and date range') but does not add new meaning beyond the schema. Baseline 3 is appropriate because the schema carries the heavy lifting.

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 states a specific verb ('List'), a clear resource ('the athlete's Strava activities'), and the ordering ('newest first'). It also enumerates the returned fields (distance, time, pace/speed, elevation gain, heart rate), which distinguishes it from sibling tools like get_athlete_profile or get_athlete_stats. The final sentence explicitly names the sibling for splits/laps, reinforcing differentiation.

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 description explicitly says when to use this tool (for a list of activities with summary metrics) and when to use an alternative ('Use get_activity_details with an activity ID for splits and laps'). It also mentions the available filters (sport type and date range), giving clear context for invocation. This is strong routing guidance.

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