index_snapshot_ohlc

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

No annotations are provided, so the description carries the full burden. It mentions 'Real-time' and 'current-day', but does not disclose data latency, output structure, pagination, error handling, or any side effects. It also does not explicitly state that this is a read-only operation. The description adds minimal behavioral context beyond the basic function.

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, front-loaded sentence with no filler. It is highly concise and easy to parse. However, the '[STANDARD]' prefix is unexplained, and the terseness borders on under-specification, though it remains effective as a brief summary.

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 simple 2-parameter snapshot tool, the description is too sparse given the rich sibling set. It lacks guidance on when to use this tool versus index_snapshot_price, index_snapshot_market_value, or index_history_ohlc. While the schema covers parameters, the description does not provide necessary usage context or clarify the scope of 'current-day'.

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?

The input schema provides descriptions for both parameters (symbol and min_time), achieving 100% schema description coverage. The tool description adds nothing about parameters, but the schema already documents their meaning sufficiently. Baseline of 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 clearly states the tool provides 'Real-time current-day OHLC for an index', which conveys the action (retrieve snapshot) and resource (index). It distinguishes from historical OHLC tools by emphasizing 'current-day', but does not explicitly mention sibling alternatives.

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 'Real-time current-day' implies this tool is for current intraday data, as opposed to historical or end-of-day tools. However, there is no explicit guidance about when to choose this over index_snapshot_price, index_snapshot_market_value, or index_history_ohlc. It gives a clear time scope but lacks explicit when/when-not guidance.

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