get_best_efforts

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

Annotations only cover read-only/open-world, so this description carries the rest and does so well: it discloses the return shape (average in W/bpm/m/s with pace, elapsed h:mm:ss, sample indices usable as start_index/end_index), a notable edge case (windows spanning a recording pause are flagged), a hard limit (longer than the activity = not available), and cost (one API call per duration or distance plus 1-2).

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 the 'Use for...' purpose and organized into purpose / returns / limits / alternatives / method, with no filler sentences. It is dense and abbreviation-heavy (W, bpm, m/s, h:mm:ss) and runs long, but every clause carries information.

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 fully compensates by documenting return fields, units, index semantics, pause flagging, defaults and a known unavailability condition, and it names the sibling tools for adjacent use cases. An agent has everything needed to call it correctly and interpret the result.

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%, so the baseline is 3, but the description adds real meaning beyond the schema: it explains the durations/distances interplay ('added to durations', 'longer than the activity = not available'), the default duration set, and the practical use of stream values like velocity_smooth with distances to get the fastest km.

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 precise verb and resource ('peak efforts of one activity: best average power, HR or speed over durations (s) or distances (m)') and gives concrete examples (peak 5 s to 20 min power, fastest km of a run). It clearly distinguishes itself from siblings compare_best_efforts and get_athlete_power_curves.

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?

Explicitly routes the agent: 'Use for the peak efforts of one activity', 'Several activities: compare_best_efforts', 'period bests: get_athlete_power_curves', plus a pointer to the method guide. When-to-use and which alternative to pick are both stated, not inferred.

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