cnb

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

With no annotations provided, the description carries the full burden. It discloses key behavioral traits: the use of official ČNB rates, cross-rate conversion logic (e.g., 'goes via CZK cross-rate'), and optional historical data. However, it lacks details on error handling, rate limits, or authentication needs, which are important for a conversion tool.

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 the core purpose stated first, followed by examples and an optional parameter note. Every sentence adds value without redundancy, making it efficient and easy to parse.

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 (currency conversion with cross-rates), no annotations, and no output schema, the description is mostly complete. It covers purpose, usage, and key behaviors, but lacks details on output format (e.g., what the result includes) and error cases, which would enhance completeness.

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 fully documents all parameters. The description adds minimal value beyond the schema, only implying that 'date' is optional for historical rates, which is already clear from the schema's optional flag and description. No additional syntax or format details are provided.

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 ('convert an amount between two currencies') and resources ('using official ČNB rates'), and distinguishes it from siblings by focusing on conversion rather than rate lookup (get_rate, get_rates). The examples further clarify the action.

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 this tool (currency conversion with ČNB rates) and includes an optional parameter hint ('Optional `date` for historical conversion'), but does not explicitly state when not to use it or name alternatives like the sibling tools for rate-only queries.

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

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

With no annotations provided, the description carries the full burden. It discloses that it returns CZK rates and can fetch all rates if no code is given, which is useful behavioral context. However, it lacks details on error handling, rate limits, authentication needs, or what 'quick' entails (e.g., performance expectations), leaving gaps for a mutation-free read operation.

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 highly concise and front-loaded, consisting of just two sentences that efficiently convey the tool's core functionality and parameter behavior. Every sentence earns its place with no wasted words, making it easy 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 low complexity (a read-only lookup with two parameters) and no output schema, the description is somewhat complete but has gaps. It explains the return value (CZK rates) and parameter effect, but lacks details on output format, error cases, or how 'date' interacts with 'code', which could be important for full understanding.

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 both parameters thoroughly. The description adds marginal value by implying that omitting 'code' returns all rates, which isn't explicit in the schema. However, it doesn't provide additional syntax or format details beyond what the schema offers, meeting the baseline for high 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: 'Quick single-currency lookup' specifies the action and scope, and 'Returns just the CZK rate for one currency (or all rates if no code given)' clarifies the output. However, it doesn't explicitly differentiate from sibling tools like 'convert' or 'get_rates', which would be needed for 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 implies usage by mentioning 'if no code given' for all rates, suggesting when to omit the parameter. But it doesn't provide explicit guidance on when to use this tool versus alternatives like 'get_rates' or 'convert', nor does it specify exclusions or prerequisites, leaving some ambiguity.

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

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

With no annotations provided, the description carries the full burden. It discloses that it returns data from a daily sheet with ~31 currencies, which adds useful context beyond the schema. However, it lacks details on error handling, rate limits, or authentication requirements that would be helpful for a tool fetching external data.

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 two sentences with zero waste: the first states the purpose and scope, the second explains the parameter usage. It is front-loaded with essential information and appropriately sized for a simple tool.

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 low complexity (1 optional parameter, no output schema, no annotations), the description is mostly complete. It covers purpose, parameter usage, and data scope. A minor gap is the lack of output format details (e.g., structure of returned rates), but this is acceptable for a score of 4.

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 schema description coverage is 100%, so the baseline is 3. The description adds value by explaining the semantics of the 'date' parameter: it's optional, used for historical rates, and defaults to latest if omitted. This clarifies usage beyond the schema's pattern validation, justifying a score above baseline.

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 action ('Get'), resource ('official CZK exchange rates published by ČNB'), and scope ('all currencies from the daily sheet (~31 majors)'). It distinguishes from sibling tools by specifying it returns all currencies rather than a single conversion or rate.

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 optional 'date' parameter (for historical rates) versus omitting it (for latest rates). However, it does not explicitly mention when to use this tool versus the 'get_rate' or 'convert' sibling tools, which would be needed for a score of 5.

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