list_activities

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

With no annotations, the description does useful work by declaring '(read-only)' and naming the returned fields (id, name, type, start, distance, HR). However, it omits ordering, the effective time window, and how the default days/limit values interact, which matters for a tool whose whole behavior is a filtered fetch.

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?

A single front-loaded sentence with no filler; the field list is worth including. Minor cost is the abbreviation 'HR' and the field enumeration crowding out parameter explanation.

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 simple read-only list tool with no output schema, listing the returned fields covers the return-value burden and 'read-only' covers safety. Still missing are the two parameters' meaning and the default/ordering behavior, which an agent needs to call it correctly.

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 0% and the description never explains 'days' or 'limit' — the only hint is the adjective 'Recent', which is far too loose to convey that days defaults to 30 and limit caps result count. The description must compensate here and does not.

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 (list) and resource (activities) plus the source (Strava), which distinguishes it from siblings like list_scheduled and list_marathons. It also enumerates the returned fields, but never says explicitly that this is a Strava-activity listing versus other activity types.

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?

Only the word 'Recent' implies a use case; there is no statement of when to prefer this over list_scheduled or the fitness-assessment tools, and no mention of prerequisites such as a connected Strava account. The agent must infer the scenario entirely.

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