playlists_get_active_presentation_thumbnail

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

No annotations are provided, so the description carries full burden. It states 'Get thumbnail' which implies a read-only operation, but doesn't clarify permissions, rate limits, error conditions, or what 'active' means dynamically. For a tool with two required parameters and no output schema, this leaves significant behavioral gaps unaddressed.

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 a single, clear sentence with zero wasted words. It's front-loaded with the core action and resource, making it easy to parse. Every word earns its place, achieving optimal conciseness for the given purpose.

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 the tool's complexity (two required parameters, no annotations, no output schema), the description is inadequate. It doesn't explain what a 'thumbnail' returns (e.g., image data, URL, metadata), how 'active' is determined, or error handling. With rich sibling tools and no structured support, more context is needed for reliable use.

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 description coverage is 100%, with both parameters ('index' and 'cueIndex') documented in the schema. The description doesn't add any parameter-specific context beyond implying these are needed to locate the 'active playlist presentation item'. Since the schema does the heavy lifting, the baseline score of 3 is appropriate.

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 'Get thumbnail for active playlist presentation item' clearly states the verb ('Get') and resource ('thumbnail for active playlist presentation item'), making the purpose understandable. However, it doesn't distinguish this tool from similar siblings like 'playlists_get_active_announcement_thumbnail' or 'playlists_get_thumbnail', leaving ambiguity about when to use this specific tool versus those alternatives.

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 provides no guidance on when to use this tool versus alternatives. With many sibling tools dealing with thumbnails, playlists, and presentations, there's no indication of prerequisites, constraints, or comparative context. The agent must infer usage from the name alone, which is insufficient for reliable tool selection.

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