playlistItems_list

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

Since no annotations are provided, the description carries the burden of revealing behavior. It discloses that the call will be rejected if both filters are omitted, and mentions the quota cost. It does not elaborate on pagination or other behaviors, but the schema already hints at pagination via pageToken and maxResults parameters.

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, consisting of three short sentences. It is well-structured: first states the action, then the key constraint, and finally the quota. No unnecessary words or redundancy.

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 schema provides parameter descriptions and the description adds the filter requirement and quota, the tool is fairly well-covered. It lacks explicit mention of output formatting, but since no output schema is provided, it is acceptable. Overall, it is sufficient for a developer to understand how to call the tool.

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 description adds meaning beyond the schema by specifying the mutual exclusivity requirement for playlistId and id. This is critical for correct usage and is not evident from individual parameter descriptions. It also clarifies that at least one of these two must be provided, which is a valuable addition.

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 the tool's function: 'Get items in a YouTube playlist.' It specifies the resource (playlist items) and the action (getting/listing), which distinguishes it from sibling tools like insert, update, or delete. The mention of the required filter (playlistId or id) further clarifies its specific purpose.

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 important usage constraints: it requires exactly one of playlistId or id, and warns that omitting both will cause rejection. It also notes the quota cost, which helps users understand the resource implication. However, it does not explicitly contrast with sibling tools for when to use this vs. others, though the purpose makes it obvious.

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