get_latest_date

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

While annotations already mark the tool as read-only and non-destructive, the description adds crucial behavioral details: the data lag (1-2 business days), the resulting 404 error on versioner endpoints with today's date, and the ValueError on reserved titles. This goes beyond the structured annotations and gives the agent essential knowledge to sequence calls correctly.

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 fairly long, but every portion serves distinct purposes: the warning highlights a critical usage timing, the title mapping gives practical examples, and the error note sets expectations. The layout is clear, starting with the main purpose, then the caution, then defaults/exceptions. Some redundancy exists but overall it remains focused and front-loaded with the most important safety note.

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 tool is simple (one parameter) and has an output schema; the description covers all that an agent needs before the call: when to use, what default to rely on, which titles are meaningful, and what exceptions to expect. It does not attempt to describe the return structure (unnecessary due to the output schema) but still completes the contextual picture of why this tool exists and how to safely call it.

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 provides the integer type and default, but no further meaning. The description compensates by clarifying the default is title 48, listing other common titles, and implicitly stating that valid titles are 1-50 via the error condition. This is valuable semantic grounding for an otherwise bare schema, though the description does not explicitly duplicate the parameter name 'title_number'.

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 states the tool's specific action: 'Get the most recent available date for a CFR title.' This clearly distinguishes it from siblings like get_version_history or find_recent_changes which focus on changes or versions. It also explicitly mentions the fallback usage as a pre-call for other endpoints.

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 gives explicit when-to-use instructions: 'Call this first to get the safe date, then pass it to other tools' for avoiding 404 errors. It includes a concrete warning about eCFR lag and explains partial error behavior with reserved titles, effectively instructing the agent on the proper invocation context. It also provides default and common titles to manage expectations.

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