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

Annotations provide readOnly, idempotent, not destructive. Description adds return format (base64 + data URI with dimensions, content type) and cost, which are useful beyond annotations.

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?

Two sentences, front-loaded with purpose and selectors, concise with no wasted words. Includes critical details like output format and cost efficiently.

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 output schema exists and annotations are rich, description fully explains tool purpose, parameter usage (via selector patterns), return value format, and cost. No gaps identified.

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% (baseline 3). Description adds grouping of selectors (artist+title, q, or id) and mentions kind defaults, enhancing understanding of parameter usage.

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?

Description clearly states it returns album cover art via Discogs with specific output format. It mentions selectors and pairs with get_music_album, but does not explicitly differentiate from siblings beyond that.

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?

Implies usage context by stating same selectors as /api/music/album and that it pairs with that endpoint, but lacks explicit when-to-use vs alternatives or exclusions.

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