Strava Activity Zones

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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the behavioral caveat 'when available', which is useful, but it does not disclose privacy_mode semantics or the explicit_user_intent requirement beyond what the schema provides. No contradiction with annotations.

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 a single 9-word sentence, front-loaded with the core action and resource. No filler or redundant information. It is as concise as possible while conveying the essential purpose.

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?

The tool has a fairly rich schema (4 parameters, including a sensitive privacy_mode with explicit_user_intent) and an output schema, but the description does not hint at these complexities. It adequately states the core function but leaves the agent to discover privacy overrides and availability conditions through the schema. Given the annotations and output schema, this is minimally acceptable but incomplete for full contextual navigation.

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 75% (3 of 4 parameters have descriptions), so the schema carries most parameter meaning. The description's 'for an activity' reinforces the required 'id' parameter but adds no new semantics for privacy_mode, response_format, or explicit_user_intent. Given moderate coverage, the description does not meaningfully augment the schema.

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 uses a specific verb 'Get' with a clear resource 'heart-rate/power zones for an activity', which distinguishes it from sibling tools like strava_get_zones (athlete zones). The phrase 'for an activity' explicitly scopes the tool to activity-level data, making its purpose unambiguous.

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 provides some implied usage guidance via 'when available', indicating zones may not exist for all activities. However, it does not explicitly contrast with sibling tools like strava_get_zones or strava_get_activity_streams, nor does it mention the required activity ID or privacy mode considerations. The agent must infer context from the schema and sibling names.

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