download_files

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

Discloses key behavioral traits: local storage path, caching behavior for already-downloaded files of same size, and return of local paths. No annotations exist, so the description carries the full burden. Could mention error handling or file overwrite behavior, but current detail is sufficient.

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 concise, with no superfluous words. The key action and parameters are front-loaded, and caching detail is placed logically at the end.

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?

Given no output schema, the description explains the return value and caching. It covers the main workflow but could mention error handling or prerequisites (e.g., course_id must exist). Overall, it is fairly complete for a straightforward download tool.

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 description adds meaning for fileurls by linking it to list_files output. However, course_id is not described beyond being required, and its source (e.g., from list_courses) is not mentioned. Schema description coverage is 0%, so the description partially compensates.

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 clearly states the action ('Download course files'), the destination ('./materials/<course>/'), and the output ('return local paths'). It differentiates from sibling tools like list_files, which only list URLs without downloading.

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?

Explicitly tells when to use the optional fileurls parameter (to download specific files from list_files) and when to omit it (to download all files). This provides clear usage guidance.

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