get_etf_details

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, covering the safety profile. The description adds that detail fields are upstream-defined and flexible, informing agents that the response shape may vary. This is useful but minimal; no mention of rate limits, errors, or other behavioral specifics.

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 short sentences with no filler. The key differentiator ('beyond info') is front-loaded, and the second sentence warns of flexible fields. Every sentence earns its place.

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 one parameter, output schema present, and annotations covering safety, the description is adequate for an agent to invoke correctly. The 'upstream-defined and flexible' caveat warns of variable response fields, which is important. It does not explain what 'extended' entails, but the output schema resolves the return structure.

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 coverage is 100% and the parameter description clearly distinguishes order_book_id from instrumentId. The tool description adds no further semantic value for the parameter, so 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?

States a specific verb ('Get') and resource ('extended ETF details'), and explicitly contrasts with 'info', which maps to sibling get_etf_info. However, 'extended' and 'flexible' are vague and do not specify what additional data is returned.

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?

'Beyond info' implies use when basic info from get_etf_info is insufficient, providing clear context. It does not name the alternative tool explicitly or give a when-not condition, but the context is enough for an agent to infer the appropriate choice.

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