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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds useful context about what the returned plan contains (meals, foods, amounts, macros), which helps the agent understand the response despite there being no output schema. No annotation contradiction.

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 definition is a single short sentence with no wasted words, and it front-loads the key fact that this returns one plan and what that plan includes.

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?

For a simple one-parameter read tool with rich safety annotations and a fully documented parameter schema, the description is nearly complete: it states scope and the main return contents. It slightly lacks explicit routing guidance relative to list_diet_plans, but the schema supplies the id source.

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%, and the sole parameter planId is documented as 'Id from list_diet_plans.' The description does not add syntax or meaning beyond what the schema already provides, so baseline 3 is appropriate.

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 identifies the resource ('diet plan') and scope ('One'), and lists the contents returned: meals, foods, amounts and macros. It is clear enough to distinguish this from sibling list_diet_plans by singular retrieval, though it omits an explicit verb like 'get' or 'retrieve'.

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?

Usage is implied rather than stated: 'One diet plan' suggests fetching details for a single plan, and the schema's planId description points to list_diet_plans. However, the description itself does not explicitly say when to use this versus list_diet_plans or other diet-related tools such as get_diet_adherence.

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