snb_get_exchange_rates

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

Annotations already declare readOnlyHint, destructiveHint, and idempotentHint, so the description does not need to repeat these. It adds value by detailing the data source (SNB cube 'devkum'), the expression of rates (CHF per foreign currency unit with examples), and the optional month-end rates. It also specifies the return format (Markdown table with metadata), enriching the behavioral context.

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 with a clear opening, a bulleted argument list, and a return format section including a JSON schema. It is slightly verbose but front-loaded with the main purpose. The organization aids readability.

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?

The description covers all essential aspects: data source, parameter details with defaults, return format (Markdown table), and an output schema. Combined with comprehensive annotations and no missing critical information, it is fully adequate for an agent to use the tool correctly.

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?

Although the input schema has descriptions for each sub-property, the tool description adds a concise summary with examples and defaults (e.g., 'Default: 12 months ago'). It explains the meaning of the rates and references snb_list_currencies for currency IDs, enhancing understanding beyond the schema.

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 it retrieves monthly CHF exchange rates from the Swiss National Bank, using a specific verb ('Retrieve') and precise resource ('monthly CHF exchange rates'). It distinguishes itself from sibling tools like snb_get_annual_exchange_rates by focusing on monthly data.

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 when to use (for monthly exchange rates) but does not explicitly provide when-not-to-use or alternatives. Sibling tools exist for annual rates or conversion, but no guidance is given on choosing between them. This is adequate but lacks explicit direction.

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