get_habit_checkins

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

With no annotations, the description carries the full burden. It discloses that the tool returns complete check-in objects for the given date range, and the example clarifies input expectations. It does not mention edge cases like date inclusivity or empty results, but for a read-only retrieval tool the disclosure is adequate.

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 well-structured: a clear one-sentence purpose, a brief benefit statement, labeled arguments, and a concrete example. Every line adds value with no redundant or filler content.

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, the existing output schema, and no annotations, the description covers all necessary aspects: what it does, how to specify parameters, and a practical use case. No major gaps are apparent.

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?

Despite the schema having 0% description coverage, the description fully explains all three parameters: habit_ids accepts a single ID or list, from_date is a YYYYMMDD integer, and to_date is a YYYYMMDD integer. The example further reinforces the format and usage.

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 uses a specific verb ('Get') and resource ('habit check-in records') with an explicit date-range scope. It clearly distinguishes itself from siblings like checkin_habits (which writes check-ins) and get_habit/get_all_habits (which fetch habit definitions).

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 use cases: analyzing streaks, completion rates, and finding missed days without a second lookup. It does not explicitly name alternatives or when-not-to-use conditions, but the context strongly implies when this tool is appropriate.

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