get_stats

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

No annotations are provided, so the description must shoulder the full burden of behavioral disclosure. It does state the specific output metrics (total items, due today count, average ease factor) and the optional scoping, but it does not explicitly confirm the operation is read-only, nor does it mention any side effects, error conditions, or response format. The description gives partial behavioral context but is not comprehensive.

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, compact sentence that front-loads the purpose ('Summary stats:') then enumerates the outputs and the optional scoping. There is no wasted phrasing or repetition; each segment earns its place. It is appropriately concise and well-structured for rapid parsing.

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, with one optional parameter, and the description covers its primary outputs and the scoping option. It lacks an explicit statement of read-only behavior and the exact output shape, but given the tool's simplicity and the absence of an output schema, the description provides sufficient context for an agent to invoke it correctly. The main gap is the unstated read-only guarantee, which is minor because the function's name and description strongly imply 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 schema has one optional parameter 'topic' with zero description coverage. The description adds meaning by explaining that the tool is 'optionally scoped to one topic', directly addressing the parameter's purpose and optionality. It does not specify the default behavior when omitted or acceptable topic formats, but given the single simple parameter and the description's acknowledgment, it compensates well for the schema's lack of documentation.

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: it provides summary statistics (total items, number due today, average ease factor) with optional topic scoping. This distinguishes it from sibling tools like get_due_items (which likely lists individual due items) and get_forecast (which projects future trends). The verb 'get' plus the resource 'stats' is explicit and 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 indicates this tool is for summary statistics, implying use when an aggregate overview is needed rather than detailed item lists. However, it does not explicitly name alternative tools or state when not to use it, leaving the agent to infer the appropriate context from the purpose. Clear context is provided, but no exclusions or comparisons to siblings are given.

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