get_fasting_history

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, so the safety profile is known. The description adds valuable behavior beyond annotations: returned fields (status, timestamps, duration) and default date behavior (30 days ago to today), which helps the agent understand what a call will produce.

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 compact and front-loaded: the core purpose appears first, then return contents, then parameter details. Every sentence contributes useful information without redundancy or filler.

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?

With only two optional parameters, rich annotations, and an output schema present, the description covers the essential call context: what is fetched, the default range, and the date format. Minor details like timezone handling or status enumeration are not specified, but these are not critical given the output schema and the simple read-only nature of the tool.

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 only shows nullable string parameters with null defaults and 0% description coverage. The description compensates by documenting start_date and end_date as YYYY-MM-DD with explicit defaults, giving the agent the format and semantics needed to invoke the tool correctly.

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 opens with a specific verb and resource: 'Get fasting history from Cronometer.' It then clarifies exactly what is returned—'fasts within the date range including status, timestamps, and duration'—which distinguishes it from related siblings like get_fasting_stats, add_fast, or delete_fast.

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 a fasting history within a date range is needed, and the date-range context is clear. However, it does not explicitly mention alternatives or when not to use this tool, leaving the agent to infer the boundary against siblings like get_fasting_stats.

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