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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds useful context about the data scope (one UTC day, per venue) and included fields, but it does not disclose behaviors such as response shape, empty-data handling, or how venues are represented in the output.

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 a single informative sentence followed by a short purpose clause. It is front-loaded with the core data content and contains no filler or redundant restatement of the tool name.

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 moderately complex data-retrieval tool with no output schema, the description lists the returned fields and scope, which helps an agent understand what it will get. However, it omits practical invocation details such as how date and interval interact, what 'per venue' means in the result, and any caveats about data availability. The schema fills some gaps, but the description is not fully complete on its own.

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 only 33%, and the description does not compensate. It mentions 'for a symbol' but does not explain symbol format or accepted values, and it does not clarify the date or interval parameters beyond what the schema already states. The description adds little semantic value for the parameters.

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 returning one UTC day of trade-flow candles for a symbol, per venue, and enumerates the specific metrics included (OHLCV, aggressor volume, buy pressure, VWAP, trades). This is a specific verb+resource description that distinguishes it from generic candle tools like get_candles, though it does not explicitly name a sibling.

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 phrase 'For backtesting and research' gives an implied usage context, suggesting when an agent might choose this tool. However, it does not explicitly state when to prefer this over alternatives such as get_candles or backtest_signals, nor does it provide exclusions or when-not-to-use guidance.

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