upsert_and_log

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

With no annotations provided, the description carries the full behavioral burden. It clearly discloses the conditional mutation behavior: if the food exists it logs immediately; if not, it creates the custom food with supplied nutrition data and then logs it. It also explains the duplicate-avoidance side-effect. A minor gap is that it doesn't clarify whether nutrition values are used when the food already exists, but the core behavior is transparent.

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 a one-sentence summary, followed by a brief behavioral explanation and a tight Args list. Every sentence earns its place, and the Args section is structured to be easily parsed by an agent.

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 10-parameter write operation with no annotations, the description covers the workflow, side effects, parameter semantics, and when to use it. Since an output schema exists, omitting return-value details is acceptable. The main unresolved point is what happens to supplied nutrition data when the food already exists, but overall the description is sufficient for correct selection and invocation.

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 0%, and the description fully compensates by documenting all ten parameters with meaningful semantics: date and time formats, timezone/meal determination, per-serving meanings, unit semantics, and defaults. This goes far beyond the bare schema types and titles.

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, compound verb+resource statement: 'Find-or-create a custom food then log it in one step.' It then explains the conditional flow clearly, which distinguishes it from siblings like create_custom_food, log_custom_food, and search_foods by emphasizing the combined upsert-and-log behavior.

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 frames the tool as a one-step alternative to separate search → create → log round-trips and says it avoids duplicate food entries. This gives clear context for when to use it. It does not explicitly name sibling tools to avoid, but the usage intent is clear enough.

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