download_activity

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

Annotations declare readOnlyHint=true and openWorldHint=true, so safety is partly covered. The description adds the default value ('ORIGINAL') for format, which is minor. It omits anything about what the download returns (file bytes? URL?), auth constraints, or size limits – the critical behavior for a download tool.

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?

It is short, but it is not front-loaded with purpose – it opens with a raw type definition rather than telling the agent what the tool does. Brevity here reflects missing content, not efficiency.

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 a download/mutation-adjacent tool, the description should explain what is returned and when to use it. Instead it covers only one parameter's enum, leaving the tool's core behavior entirely undocumented.

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 50%. The description documents the `format` enum and default, which the schema's enum already implies, and says nothing about `activityId` (schema only notes 'Numeric id'). It adds the default, so slightly above baseline for the covered param but leaves activityId semantics to 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 never states what the tool does. It only documents the `format` enum values and default, giving no verb+resource like 'download an activity file'. An agent cannot tell from this text that this tool downloads activity data, nor how it differs from siblings like get_activity or download_course_gpx.

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?

There is no when-to-use guidance, no mention of alternatives (e.g., get_activity_details returns data rather than a downloadable file), and no conditions for selecting a format beyond the enum list itself.

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