Instrument 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 useful context about the returned content, including trading sessions and trade size fields, but does not detail response behavior beyond that. No contradiction exists.

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. It begins with the core purpose and then enumerates the relevant specification fields without redundant wording.

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 reference-data lookup, the description gives enough content detail to convey what the tool returns. It relies on the schema for parameter prerequisites and defaults, which is acceptable since schema coverage is 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?

Schema description coverage is 100%, so the schema already documents uic, assetType, and includeTradingSchedule. The description lists output content rather than parameter semantics, so it adds little beyond the schema; baseline 3 applies.

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 resource (one instrument) and the kind of data returned (contract specification: currency, exchange, tick size, lot size, trading sessions, etc.). It is specific enough to be distinguishable from price or chart tools, though it does not explicitly name 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 usage context is implied: after obtaining a uic and assetType, an agent would call this tool to fetch static reference data. However, the description does not explicitly state when to use this tool versus search_instruments, get_instrument_price, or other siblings.

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