pro_get_candles

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

Annotations already indicate read-only, idempotent, and non-destructive behavior. The description adds useful behavioral context beyond that: default time window of 24 hours, limit max of 1000, public access, and return shape as a list of candles with metadata. No contradiction with annotations.

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?

The description is front-loaded with the core action and resource, then each sentence adds useful constraints or defaults. It is slightly wordy with phrases like 'timestamp and date' and 'list of candles with metadata' that partially overlap, so it does not reach a 5.

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 read-only market data tool with no output schema, the description covers the essential invocation details: required inputs, optional params, defaults, max limit, and high-level return type. It lacks explicit ordering or inclusiveness details for time bounds, but is otherwise sufficient.

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?

Input schema coverage is 100%, so parameters are already fully documented. The description reinforces pair/timeframe requirements and adds the Unix epoch milliseconds details and 24-hour default, but does not add meaningfully beyond the schema. Baseline 3 is appropriate.

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 states a specific verb ('Gets') and resource ('OHLCV candles for Pro Advanced Trading'), and clearly distinguishes it from sibling market-data tools like pro_get_ticker or pro_get_order_book by focusing on historical candle data. It also enumerates the data fields returned, making the purpose unambiguous.

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 explicitly identifies the intended use case ('Essential for technical analysis and charting') and notes the endpoint is public. It does not name alternatives or state when not to use this tool, but the context is clear enough for an agent to select it appropriately.

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