list_activities

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

No annotations are provided, so the description carries the burden. It usefully discloses the default no-date behavior (returns most recent) and the limit=1 shortcut, which is real behavioral value. But it says nothing about auth/permissions, pagination, ordering, or how many results come back by default beyond the schema's stated default.

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?

Two tight sentences with the default-case behavior front-loaded before the ranged/filtered case. No filler, though the parenthetical examples for type are partly redundant with the schema's own examples.

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 and no annotations, this description is nearly sufficient: it covers invocation modes (default vs ranged vs filtered) and the key shortcut. The remaining gap is only return-shape and ordering, which is a modest omission for a list tool.

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 baseline is 3. The description adds intent for how parameters combine (dates and/or type filter the range) and a concrete limit=1 use case, which is slightly beyond the schema, but format/default details remain the schema's job.

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+resource ('List activities') and immediately scopes behavior by date/type, which distinguishes it from the singular get_activity sibling in practice. However, it never explicitly names get_activity or get_steps_history as alternatives, so sibling differentiation is inferential rather than stated.

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?

Gives clear conditional guidance: omit dates for the most recent activities, use limit=1 for the last activity, pass startDate/endDate and/or type for a ranged/filtered query. Missing is any 'do not use this when...' or pointer to the detail tool get_activity for a single record.

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