list_timezones

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

With no annotations provided, the description carries the full burden. It usefully discloses that query matching is case-insensitive and substring-based, but does not mention read-only behavior, result size, or what happens when query is empty. The disclosure is helpful but minimal.

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 two efficiently worded sentences with no filler. The primary action and the key parameter behavior are both stated clearly and concisely.

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 tool with one optional param and an output schema, the description is sufficient for an agent to understand its purpose and the query behavior. It could be slightly more complete by noting empty-query behavior or explicitly relating itself to sibling tools, but these are minor gaps.

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 coverage is 0%, so the description must clarify the query parameter. It does so by explaining it is a case-insensitive substring match. It does not describe the default behavior, but the default is visible in the schema and the core meaning is conveyed.

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 searches available IANA timezone names, which is a specific verb and resource. It also naturally distinguishes itself from sibling tools like get_local_time and get_time_in_timezone, which retrieve times rather than listing/searching names.

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 usage: use this tool when you need to find timezone names via substring matching. It does not explicitly mention alternatives or when not to use it, but the sibling tool names make the distinction reasonably clear.

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