Post-meal target window analysis

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

With no annotations, the description carries the behavioral burden and mostly succeeds. It discloses the exact time window, states that times are wall-clock device-local and not UTC, and clarifies that glucose values follow the configured/overridden unit. It also outlines the returned fields. Minor caveat: the phrase 'configured unit' does not explicitly restate the effect of the units override, but the schema compensates.

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 tight and front-loaded: first the exact window, then the use case, then time/unit caveats, then the return shape. Every sentence earns its place without fluff or repetition.

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 has no output schema, but the description compensates by enumerating returned fields and their semantics. It also covers the key operational details: wall-clock times, unit conventions, and how to obtain the required timestamp. Nothing essential is missing for a caller to invoke it correctly.

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?

Schema description coverage is 100%, so the schema already explains both parameters thoroughly. The description adds context about the event source and the analysis window, but it does not materially enhance the meaning of eventTimestamp or units beyond what the input schema already provides.

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 identifies the tool as a focused single-event analysis: 'exactly 30 minutes before and 3 hours after the timestamp you pass.' It distinguishes itself from broader sibling tools by saying 'without pulling whole days' and even points to a specific sibling for the prerequisite event time.

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?

It explicitly states when to use the tool: 'Use it to judge a post-meal excursion and how well a dose worked.' It also gives a concrete workflow by directing the user to find the event time from get_enriched_bolus_log first. It does not enumerate every alternative or exclusion, but the guidance is clear and actionable.

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