add_rest

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

With no annotations, the description must disclose behavioral traits like side effects (modifying the current workout) or required state. It only says 'Add' without clarifying that it appends to an existing workout or if it requires a created workout. The agent is left guessing about context and mutability.

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 extremely concise: one sentence for purpose followed by a clear parameter definition with format and example. No redundant words. It is front-loaded and structured with a labeled Args section, earning its place.

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 simplicity (1 parameter) and existence of an output schema, the description minimally covers the functionality. However, it does not explain the overall context (e.g., that this step is added to a workout under construction) or mention related concepts like ordering. It is adequate but lacks completeness for a full behavioral understanding.

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 coverage is 0%, so the description must compensate. It explains the 'duration' parameter with format 'M:SS' and an example. This adds sufficient meaning beyond the schema, though a note that minutes and seconds are digits would improve clarity. The explanation is adequate for a single simple parameter.

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 'Add a rest step,' identifying the verb (add) and resource (rest step). It distinguishes from sibling tools like add_exercise or add_bike, which are different step types. However, it could be more explicit about the context (e.g., adding to a workout definition), but the purpose is 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?

No guidance on when to use this tool versus alternatives such as add_recovery or add_cooldown. The description does not mention prerequisite conditions (e.g., an active workout), making it hard for an agent to decide when to invoke it.

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