list_diary_groups

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It clearly explains what the tool returns (wire_index, name, enabled status), clarifies that wire_index is the 0-based value expected by add_food_entry, and warns about user-configured names. This gives the agent actionable behavioral context beyond a generic list operation.

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 front-loaded with the core purpose and result, then adds necessary caveats about user-configured names and enabled-state restrictions. Each sentence earns its place; there is no filler 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 description fully prepares the agent for the tool's role in the workflow: it explains what data is returned, what that data means for downstream calls to add_food_entry, and the practical gotchas about custom names and enabled groups. Given the simple no-input nature of the tool, no additional context is needed.

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 tool has zero parameters, so parameter semantics are inherently trivial. The description adds useful meaning by explaining what the returned wire_index means in the context of add_food_entry, which compensates for the empty schema. The baseline of 4 applies since no parameter documentation is needed.

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 lists diary groups and explicitly ties the returned values to what add_food_entry accepts. This distinguishes it from sibling tools that log food or retrieve nutrition data, leaving no ambiguity about its purpose.

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 explicitly instructs the agent to call this tool before assuming a diary group name exists, and it explains why: names are user-configured and may differ from defaults. It also notes that only enabled groups are writable, giving clear guidance on when and how to use the result for add_food_entry.

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