get_album_cover

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

No annotations exist, so the description must carry the behavioral disclosure burden. It states the tool returns a URL, implying a read-only operation, but it does not address error cases, URL persistence, or any prerequisites. This is adequate but not rich for a simple getter.

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 and well-structured with an Args/Returns format. It front-loads the primary purpose and includes only necessary details without any fluff.

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 simple tool, the description covers purpose, parameters, and return value adequately. It is complete for a read-only URL getter. Minor gaps include not referencing sibling tools or explaining where album_mid originates, but these do not significantly hinder usability.

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 has zero description coverage, but the description explains album_mid as the album MID identifier and lists common size values (150, 300, 500). This adds meaningful semantics beyond the schema, though the default size is not mentioned in the description.

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 '获取专辑封面图片 URL' (Get album cover image URL), naming a specific verb and resource. This distinguishes it from sibling tools like get_song_url or get_album_detail.

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 implies usage for retrieving album cover URLs but does not explicitly state when to use this tool over alternatives. No exclusions or cross-references to siblings are provided, making the usage guidance merely implied.

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