get_playlist_items

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

With no annotations present, the description must carry the behavioral burden. It discloses that the call returns only a single page (not auto-paginated) and explains side effects of the market parameter (track relinking and unavailability flagging). It doesn't discuss error cases or rate limits, but for a read-only list operation this is acceptable.

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 with no filler. The primary action and scope are front-loaded, and the parameter guidance is condensed into one sentence. Every word earns its place.

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 tool with 9 parameters and no output schema, the description plus fully-described schema is sufficient for an agent to call it correctly. The single-page behavior and the market/fields/additional_types tips cover the important semantic points. It doesn't describe the exact return shape, but that's not required given the schema's parameter descriptions.

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 100% description coverage, so the baseline is 3. The description adds marginal value by summarizing why to use fields and additional_types ('trim the payload'), but it largely restates the schema's own parameter descriptions for market, fields, and additional_types. No parameter meaning is missing.

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 uses a specific verb ('List') and names the resource ('a playlist's items') and limits scope ('on a single page'). This clearly distinguishes it from sibling get_playlist, which returns playlist metadata, and from mutation tools like reorder_playlist_items. The name and description align perfectly.

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 gives clear context for when to call this tool: whenever you need the items in a playlist. It also provides parameter-level guidance, telling the agent to use market for relinking/flagging and fields/additional_types to reduce payload size. It doesn't explicitly contrast with alternatives like get_playlist, but the 'single page' phrasing implies pagination handling without needing further search.

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