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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that bars range from 1m to 1M, but does not disclose pagination behavior or rate limits. This aligns with the annotations and provides minor additional context, meeting the baseline.

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 concise sentences: the first states what the tool does and the second states its intended use. No redundant or filler content, front-loaded with the key information.

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?

With annotations covering safety and an output schema present, the description covers the main purpose and use cases. It lacks explicit parameter explanations, but the schema and examples partially compensate. For a market data tool, this is reasonably complete, though not exhaustive.

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%, so the description must compensate. It mentions 'Bars 1m through 1M,' hinting at the 'bar' parameter, but does not explain 'instId', 'after', 'before', or 'limit'. The examples give some inference, but the description itself adds minimal parameter detail.

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 identifies the tool as providing OHLC candles for OKX instruments, specifying spot/perp/futures. This distinguishes it from sibling tools like ticker, trades, and order_book by stating the exact resource and data type.

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?

It explicitly states 'Use for charting and backtesting OKX instruments,' which gives clear context for when to apply the tool. However, it does not provide explicit when-not-to-use guidance or name alternative tools, so it falls short of a 5.

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