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

The description adds real context beyond the annotations: it costs one read (explaining readOnlyHint=false) and persists the result list into the user's Puley history, a durable side effect the annotations only hint at. It does not cover failure modes or auth requirements, but the credit-cost and side-effect disclosure is the important part.

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?

Purpose is front-loaded in the first clause, then return fields, then cost/limit/history notes. It is dense and slightly run-on, but every clause carries information; nothing is filler.

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 two-parameter tool with no output schema, the description covers return shape, cost, and persistence, which is most of what an agent needs. It stops short on edge behavior such as what happens when limit exceeds 20 or whether results are deduplicated.

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?

With 0% schema description coverage, the description carries the load and does address both parameters: 'topic' is defined as the subject of the search, and 'limit' gains the ceiling 'up to 20' that the bare schema lacks. The default of 10 and any topic-format guidance remain undocumented, keeping it short of a 5.

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 YouTube channels about a topic') and immediately enumerates the returned fields (name, handle, subscribers, verified badge, description, link), which cleanly separates it from siblings like find_videos or google_results.

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?

Offers one implied scenario, 'Useful for finding creators in a niche,' but gives no when-not guidance and never names an alternative tool (e.g., find_videos or google_results) for adjacent intents, leaving the agent to infer boundaries 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.