get_market_historical_index

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

With no annotations provided, the description carries the full burden and does a solid job: it details the exact return structure, error conditions, and source metadata. It also implicitly communicates read-only behavior through the verb '取得'. It stops short of stating frequency, latency, or historical depth, but this is a strong disclosure for a simple read-only tool.

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 well-structured with sections (purpose, index list, usage, args, returns, raises) and the purpose statement is front-loaded. The 10-index list is valuable context, though the usage example more or less repeats the first line, adding slight redundancy.

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?

Given there is no output schema and no annotations, the description goes far beyond a bare phrase by documenting the full return structure and possible errors. It lacks details on time range or rendering order, but for a no-parameter tool that returns a known set of indices, this is nearly complete.

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 tool has zero parameters, which earns a baseline of 4. The description explicitly confirms 'Args: 無參數' and shows a call with empty parentheses, leaving no ambiguity for an agent.

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 action ('取得' market index data) and the resource ('市場重要指數資料'), and enumerates the 10 specific indices included. However, it does not explicitly differentiate itself from the sibling tool get_market_index_info, such as noting that this returns historical data while the other does not.

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 provides a basic usage example but gives no guidance on when to use this tool versus alternative market index tools. There is no mention of exclusions or conditions that would route an agent to a sibling tool.

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