Get Download Link (v1)

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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds account-state nuance: premium vs non-premium handling and the exact nxm:// source for the optional credentials. It does not describe error cases or return shape, but the annotations carry much of the safety burden.

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: it opens with the core purpose, then states the two usage modes. Every sentence carries necessary information, and the nxm:// template is included without filler.

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 low-complexity, read-only tool with strong annotations and 100% schema coverage, the description covers the return concept and the main conditional behavior. It does not mention alternatives like download_file, but that is a minor gap given the rest of the structured context.

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 100%, so all five parameters are already documented in the schema. The description adds value by explaining when key and expires are actually required and by providing the nxm:// link template that shows how those values relate to game, mod_id, and file_id.

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 states the resource clearly: 'CDN download URLs for a file.' It also explains the two invocation modes by premium status, so an agent understands what the tool returns. It does not explicitly differentiate from sibling tools like download_file or get_mod_files, so it is clear but not fully sibling-aware.

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 gives explicit conditional usage: premium callers work directly, while non-premium callers must pass key and expires parsed from an nxm:// link. This is actionable and precise. It does not mention alternatives or say when not to use this tool, but the context is clear enough.

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