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 effectively describes the tool's behavior by specifying required input formats (luxon format, IANA timezones) and the prerequisite tool invocation for certain scenarios. However, it doesn't mention error handling, rate limits, or authentication needs, which would be helpful for a complete behavioral picture.

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 in the first sentence. The bullet points efficiently convey important constraints and prerequisites. While every sentence earns its place, the formatting as bullet points (though clear) could be slightly more streamlined for pure text consumption.

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 (timezone conversion with format constraints), no annotations, and no output schema, the description does well by covering purpose, usage guidelines, and behavioral constraints. However, it doesn't describe the return format or error responses, which would be helpful for completeness since there's no output schema.

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 all three parameters thoroughly. The description reinforces the format requirements (luxon format, IANA timezones) but doesn't add significant semantic meaning beyond what's in the schema. This meets the baseline expectation when schema coverage is high.

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 verb ('converts') and resources ('date time string from one timezone to another'), and it distinguishes from sibling tools by not overlapping with 'currentDateTimeAndTimezone' (which provides current info) or 'mutateDate' (which suggests date manipulation rather than timezone conversion).

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 explicit guidance on when to use this tool vs alternatives: it specifies that for relative dates/times or unspecified dates, the agent must first invoke 'currentDateTimeAndTimezone' to get the user's current context. This creates clear prerequisites and distinguishes usage scenarios from the sibling tools.

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 of behavioral disclosure. It mentions that it retrieves the user's current date/time/timezone, which implies a read-only operation, but doesn't specify whether this requires authentication, how frequently it can be called, or what format the data is returned in. This leaves significant gaps for a tool with no annotation coverage.

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 a single, efficient sentence that directly states the tool's function without any unnecessary words. It's front-loaded with the core purpose and wastes no space, making it ideal for quick comprehension.

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 (0 parameters, no output schema, no annotations), the description is adequate but not fully complete. It explains what the tool does but lacks details on return format, authentication needs, or error handling. For a basic tool, this is minimally viable but leaves room for improvement in behavioral context.

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 0 parameters with 100% description coverage, so the schema fully documents the lack of inputs. The description doesn't need to add parameter details, and it appropriately doesn't mention any parameters, earning a high baseline score for this context.

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 a specific verb ('Gets') and resource ('current date, time and timezone of the user'), making it immediately understandable. However, it doesn't explicitly distinguish itself from sibling tools like 'convertTimezones' or 'mutateDate', which prevents 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 like 'convertTimezones' (for timezone conversion) or 'mutateDate' (for date manipulation). It states what the tool does but offers no context about appropriate use cases or exclusions.

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 full burden. It discloses the required date format (luxon format) and provides concrete examples, which is valuable. However, it doesn't mention error handling, whether the operation is reversible, or what happens with invalid inputs. The description adds context about format requirements but lacks comprehensive behavioral details.

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 three bullet points that each serve distinct purposes: purpose statement, format requirements, and usage prerequisites. It's front-loaded with the core functionality. Minor improvement could be made by combining some format details, but overall it's efficient.

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 (date manipulation with format constraints), no annotations, and no output schema, the description does well by covering format requirements, examples, and workflow dependencies. It could be more complete by mentioning return format or error cases, but it provides sufficient context for basic usage.

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 baseline is 3. The description adds value by providing concrete examples of both parameters (date format example and update object example), which enhances understanding beyond the schema's technical definitions. However, it doesn't explain edge cases or parameter interactions.

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 verb ('mutates') and resource ('date time string'), and distinguishes it from sibling tools by focusing on date manipulation rather than timezone conversion or current date retrieval. It specifies the exact operations (adding/subtracting days, hours, minutes, months, years).

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 explicit guidance on when to use this tool versus alternatives: it instructs to first invoke 'currentDateTimeAndTimezone' when users don't specify absolute dates (e.g., 'today', 'tomorrow'), creating clear workflow dependencies. This directly addresses when to use this tool versus the sibling tool.

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