forex_rate

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

No annotations are provided, so the description carries the burden. It discloses the return fields (current rate, change, high/low, 52-week range) which helps, but it does not mention data latency, error conditions, or rate limits. The description is adequate for a simple read tool but lacks depth.

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: a one-line purpose, a short line on return values, an Args section, and multiple examples. Every sentence is informative and no space is wasted.

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 simplicity, the description adequately covers purpose, parameters, and return values. It has an output schema (not shown but present) that likely details return structure, so the description need not. However, it lacks any note on error handling or unsupported currency codes, keeping it from a perfect score.

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 0%, so the description must explain parameters. It does so via an 'Args' section and examples (e.g., 'from_currency: Source currency code (e.g., USD, EUR, GBP, AED, JPY)'). This adds clear meaning beyond the bare schema, but could be improved with validation rules or a more formal spec.

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 'Get live forex exchange rate between two currencies' with a specific verb and resource. It also lists the return values (current rate, day's change, high/low, 52-week range), which distinguishes it from sibling tools like stock_quote or crypto_price.

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 implies usage for forex conversion and provides examples of common pairs, but it does not explicitly state when to use this tool versus alternatives (e.g., crypto_price, stock_quote). No exclusions or explicit alternative references are given, so it falls at 'implied usage'.

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