download_article_images

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

Annotations declare readOnlyHint=false and destructiveHint=false, and the description usefully adds that output lands in an exclusive local output/articles directory and that each image yields a SHA256 plus a missing-range report, plus the batch cap. It does not explain permissions or whether existing files are overwritten.

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?

A single dense sentence front-loads the action and destination, then packs return shape and batch limits with no filler. Every clause carries information an agent needs.

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, the description dutifully describes results (per-image, SHA256, missing range) and destination. Minor gaps remain around indexing semantics and overwrite behavior, but the definition is largely self-sufficient.

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 0%, so the description must compensate: it supplies the otherwise undocumented default of the first 12 images when image_indices is omitted and the 20-image per-call maximum. It does not clarify the expected 1-based indexing or the SHA256 format of article_id, both of which the schema constrains silently.

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?

States a specific verb+resource: downloading images of already-archived WeChat articles to a local directory. It clearly differs from read-oriented siblings like read_article_image and read_wechat_image by concentrating on batch local download.

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?

Implied that it operates on stored articles and gives defaults/caps (12 default, 20 max), but never states when to choose it over read_article_image or read_wechat_image, or any prerequisites for having an archived article first.

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