get_activities

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

Annotations already declare readOnlyHint=true, and the description restates 'Read-only' (redundant but consistent). It adds genuine behavioral context beyond annotations: default date window, page size, that any filter/sort/offset/format switch yields a paged listing with total and next offset, and that unnamed activities are hidden unless opted in.

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-loads the purpose and default behavior before detailing output modes, filters, and the alternative tool. It is dense and slightly overpacked across line breaks, but nearly every clause carries information useful for invocation.

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 12-parameter tool with no output schema, the description covers defaults, filters, paging, output modes, and the single-activity alternative, plus a pointer to the guide method. It is close to complete, lacking only explicit return-shape detail, which is partially implied by detail_level and output_format.

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 12 parameters, making 3 the baseline. The description reinforces the filter/sort/offset and detail_level/output_format behavior and the interaction that any of them triggers paging, but adds little syntax beyond what the schema already 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 and resource ('find activities and their ids in a date range') and gives a concrete example ('all rides on one bike over a season'). It also differentiates from the sibling for single-activity depth by naming get_activity_report, so an agent can tell it apart from the many get_activity_* tools without opening schemas.

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?

Provides clear usage context and defaults ('default the last 30 days up to today, 10 per page') and explicitly routes the agent to get_activity_report for one activity in depth. It does not state hard when-not conditions, but the scope rules (nothing outside the date range, unnamed hidden) effectively bound usage.

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