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

Annotations already mark it read-only, idempotent, and non-destructive; the description adds the exact endpoint mapping (GET /share-pass/{token}/download), the public/no-auth behavior, the active-pass prerequisite, and a warning not to invent other paths. This is substantive behavioral context beyond the hints.

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 compact and front-loaded, but it has minor redundancy: the opening line repeats the first sentence, and 'no authentication required' appears twice. This is a small efficiency issue rather than a structural problem.

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 one-parameter public download with no output schema, the description covers the endpoint, auth profile, prerequisite, and rate-limit context. It does not spell out failure modes for expired or inactive tokens, but that is a minor gap given the tool's simplicity.

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?

The schema already fully documents the single required token parameter, including its format as 32 hex characters. The description only repeats token in the path template and adds no new semantic meaning, so the baseline 3 is appropriate.

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?

Opens with a specific verb and resource ('Download shared Apple .pkpass') and the body confirms it downloads the .pkpass file for a shared pass. It also signals the distinguishing dimension—public, no-auth endpoint—so an agent can separate it from sibling download tools.

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 context: use for shared passes with a share token, only when the pass is active, and without authentication or an API key. It does not explicitly name sibling alternatives or state when not to use it, so it stops short of full alternative routing.

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