GetCurrenciesCode

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 hints at behavioral traits like the ability to expand relations or select fields, but doesn't disclose critical details: whether this is a read-only operation, authentication requirements, rate limits, error handling (e.g., for invalid codes), or the response format. For a retrieval tool with zero annotation coverage, this is a significant gap in transparency.

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 appropriately sized with two sentences that are front-loaded: the first states the core purpose, and the second adds optional features. There's no wasted text, but it could be slightly more structured (e.g., bullet points for parameters) without losing conciseness.

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 the complexity (a retrieval tool with 2 parameters), no annotations, no output schema, and low schema coverage, the description is incomplete. It lacks details on authentication, error cases, response structure, and how parameters interact. For a tool that likely returns structured data, this leaves the agent under-informed about usage and outcomes.

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 has 2 parameters with 0% description coverage, so the description must compensate. It implies 'code' is for currency identification and 'fields' for selecting return data, but doesn't explain the format (e.g., string patterns for 'code', comma-separated lists for 'fields'), required vs. optional status, or examples. This adds minimal semantic value beyond the schema's property names.

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's purpose: 'Retrieve a currency by its code.' It specifies the verb ('retrieve') and resource ('currency'), and distinguishes it from the sibling 'GetCurrencies' (which likely lists all currencies). However, it doesn't explicitly mention how it differs from 'GetCurrenciesId' (if that exists) or other currency-related tools, keeping it from a perfect score.

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 no guidance on when to use this tool versus alternatives. It mentions expanding relations or selecting fields, but doesn't specify prerequisites, error conditions, or compare it to sibling tools like 'GetCurrencies' or 'GetRegions' (which might include currency data). This leaves the agent without clear usage context.

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