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

Annotations declare readOnlyHint=false and openWorldHint=true; the description supplies the reason by disclosing "Uses one read and saves the list in the user's Puley history", which explains the cost and the side effect of a saved history entry. It also previews the returned fields per platform in the absence of an output schema. It does not cover failure modes or rate limits.

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?

Front-loaded with the core purpose, then per-platform return fields, then per-parameter constraints; almost no filler. The prose is a single run-on block with line-wrapped parentheticals, so the constraint list takes a second pass to parse.

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 5-parameter open-world search with no output schema, the description covers platform behavior, result shapes, sort/filter scope and the credit cost, which is close to everything an agent needs to call it correctly. Pagination and error behavior are the only notable omissions.

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 0% and no enums are declared, so the description carries the full burden and largely discharges it: it gives the accepted values for sort, uploaded and platform, scopes sort and uploaded to YouTube only, and caps limit at 20. Defaults are left to the schema, but every parameter gains meaning the raw schema lacks.

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 ("Find videos about a topic") and immediately enumerates what each platform variant returns, so the agent knows this is a social-video search rather than a web search. It does not name a sibling to contrast with (e.g. google_results, find_news, watch_video), so the differentiation is implicit rather than explicit.

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 makes the platform choice clear (youtube default, tiktok hashtag, instagram reels under a hashtag) and lists the sort/uploaded options, which implies when to pick each. However, it never says when to prefer this over sibling tools like google_results or find_channels, nor does it give prerequisites or exclusions.

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