add_to_playlist

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

With no annotations, the description minimally discloses that IDs are not URLs but does not mention whether adding a duplicate is safe, if the operation is idempotent, or any error conditions. A mutation tool should provide more behavioral context.

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, no filler. Front-loaded with the core action and key constraint. 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?

Despite simplicity, the description omits important context for a mutation tool: no mention of success/failure indicators, duplicate handling, or permission requirements. Leaves an AI agent underinformed for safe invocation.

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%, but the description adds value by clarifying that both parameters are YouTube IDs and not URLs, which disambiguates potential misinterpretation. This is a meaningful addition beyond the schema.

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 action ('Add a video to an existing playlist') and the resource, distinguishing it from siblings like create_playlist. The clarification that IDs are YouTube IDs (not URLs) further sharpens 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?

No guidance on when to use this tool versus alternatives, prerequisites (e.g., playlist existence), or edge cases (e.g., duplicate video). The description is purely operational without directional help.

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