get_activity_best_efforts

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

With no annotations, the description carries the full transparency burden. It discloses that the MCP preserves efforts and metadata, reports average units (W, bpm, m/s, or unknown), performs no FTP/VO2/numeric calculations, and that min_value may expand an effort while source completeness is unknown. This is substantive and beyond schema, though it omits error handling and authentication details.

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 description is moderately long but each sentence serves a purpose: it leads with purpose, then parameter constraints, then behavioral notes. It is front-loaded and structured logically, though slightly dense. It avoids fluff and stays focused on actionable 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?

Given the complexity (10 parameters, output schema present), the description covers the most critical aspects: selector requirement, index sentinels, count limit, and behavioral guarantees. It doesn't explain every parameter (e.g., exclude_intervals) but the output schema handles return structure. Overall, an agent can call this tool correctly with the provided guidance.

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 0%, so the description must compensate. It explains duration/distance constraints, start_index/end_index semantics (including end_index=0 sentinel and None omission), count limits (1..100), and min_value's effect. It does not clarify api_key, exclude_intervals, or activity_id/stream directly, but the core selectors and indices are well documented, making the tool usable.

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 opens with a clear verb and resource: 'Find upstream best efforts by one duration or distance selector.' It specifies the operation (finding ranked efforts on a named stream from Intervals.icu) and distinguishes the selector requirement. While it doesn't explicitly compare to sibling tools, the purpose is unambiguous and distinct from related tools like get_activity_intervals or get_activity_streams.

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 gives a direct usage context: 'Choose this to ask Intervals.icu for ranked efforts on a named stream.' It also clarifies a critical constraint (exactly one of duration/distance required) and sentinel behaviors for end_index. However, it does not mention alternative tools or conditions when this tool should NOT be used, so guidance is partial.

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