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

Annotations already declare read-only, idempotent, open-world, non-destructive behavior, and the description adds genuinely new context: 1 credit per result with a 1-credit minimum per request. That pricing/cost disclosure is the kind of detail annotations cannot carry. It stops short of describing pagination behavior or return shape.

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?

Three short sentences, purpose front-loaded, followed by safety and cost. No filler 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?

For a simple paginated read tool with a fully described schema and complete annotations, the description covers purpose, safety, and cost. Return-value detail is the only gap, and there is no output schema, though the schema's cursor description implies the pagination contract.

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%, so uniqueId, count, and cursor are fully documented in the schema itself. The description adds no additional meaning about parameters, which is appropriate at baseline 3.

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?

States a specific verb and resource ('Get the videos a TikTok user reposted'), and the word 'reposted' distinguishes it from tiktok_get_user_posts and tiktok_get_user_liked_videos. It does not name sibling tools explicitly, so it falls short of a 5.

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 implies usage (fetch a user's reposted videos) but gives no explicit when-to-use/when-not guidance and no routing to alternatives like tiktok_get_user_posts. Nothing is misleading, but the agent must infer selection from the name alone.

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