guess_datetime_url

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 approach by listing multiple data sources examined (e.g., HTTP headers, HTML metadata) and outputs (timestamp with confidence scores), giving a clear picture of its heuristic and probabilistic nature. However, it lacks details on error handling or performance characteristics.

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, starting with the core purpose and following with key details on methods and outputs. It avoids redundancy, though it could be slightly more streamlined by combining some of the listed data sources into broader categories.

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 complexity (heuristic datetime guessing) and lack of annotations or output schema, the description does a good job of explaining the process and return values. It covers the input parameter indirectly and outlines the output structure, though it could benefit from more explicit details on confidence score ranges or error cases.

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, with the 'url' parameter well-documented in the schema itself. The description does not add any additional meaning or constraints beyond what the schema provides, such as URL format examples or validation rules, so it meets the baseline 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 specific action ('guess the last updated or published datetime') and resource ('a web page'), distinguishing it from sibling tools like 'read_url' or 'capture_screenshot_url' that focus on different webpage interactions. It specifies the exact temporal information being extracted, making the purpose unambiguous.

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 when temporal metadata about a webpage is needed, but does not explicitly state when to use this tool versus alternatives like 'read_url' (which might return raw content) or 'parallel_search_web' (which might provide search results). No exclusions or prerequisites are mentioned, leaving the context somewhat open-ended.

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