Save a contact's zone

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

With no annotations, the description carries the full disclosure burden, but it only says 'Remember' and describes the future benefit. It does not state whether an existing contact with the same name is upserted, whether a new contact is always created, or what the tool returns/side effects are.

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?

Single-sentence, front-loaded with the core action and resource, and uses an illustrative example instead of restating schema. The phrase 'later' appears once in the main clause and once in the example, a tiny redundancy.

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 set operation, the schema plus description cover required inputs and the purpose. The main missing context is mutational behavior (create vs update) and success/failure output, which no annotation or output schema helps fill.

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?

All four parameters are documented in the schema (100% coverage), so the description does not need to repeat details. It adds only the high-level 'time zone and working hours' framing and the scheduling use case, which is sufficient but minimal.

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 uses a clear verb ('Remember') and identifies the resource ('a client or teammate's time zone and working hours'), then ties it to a concrete downstream use case. It does not explicitly contrast with contacts_list or explain whether setting overwrites, 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?

The description implies when to use the tool – when you want to store a person's zone and hours for later scheduling. It provides no exclusions or comparison with sibling tools such as contacts_list or find_meeting_slots, so an agent must infer the exact boundary.

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