NexusForge EU Finance

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the data source (ECB via Frankfurter.app) and the types of rates (latest/historical), which adds useful context. However, it does not cover potential behavioral traits like rate limits, error handling, or authentication needs, leaving gaps for a tool with external dependencies.

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 and front-loaded, with two sentences that efficiently convey the tool's purpose, capabilities, and data source without unnecessary details. Every sentence adds value, and there is no wasted text, making it easy for an agent to parse quickly.

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 tool's moderate complexity (2 parameters, no output schema, no annotations), the description is somewhat complete but has gaps. It covers the core functionality and data source but lacks details on return values (e.g., rate format, error cases) and behavioral aspects like performance or limitations, which could hinder an agent's ability to use it effectively without trial and error.

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 100% description coverage, clearly documenting both parameters (currencies and date) with formats and optionality. The description adds marginal value by reinforcing the optional nature ('Omit for all available currencies' and 'Omit for latest rates') but does not provide additional semantics beyond what the schema already specifies, aligning with the baseline score for high schema coverage.

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 with specific verbs ('Get EUR exchange rates') and resources ('against other currencies'), distinguishing it from sibling tools like get_ecb_rates by specifying the data source (ECB via Frankfurter.app) and scope (latest/historical rates). It avoids tautology by providing meaningful context beyond the tool name.

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 clear context for when to use the tool ('Supports latest rates or historical rates by date'), but it does not explicitly state when not to use it or name alternatives among the sibling tools (e.g., compare_eu_economies for broader economic comparisons). The guidance is helpful but lacks exclusion criteria.

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