list_accounts

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

The description adds the qualifier 'safe', indicating that not all aliases are safe and this tool filters to safe ones, which is beyond the annotations' read-only and idempotent flags. It does not elaborate on what 'safe' means, but the additional context is useful.

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 consists of two short, front-loaded sentences. The first sentence states the core functionality, and the second gives a usage tip. There is no redundancy or filler.

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 list command with no parameters and an output schema, the description is complete. It covers what the tool does, when to use it, and the annotations handle safety. No further detail 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 no parameters, so the description need not explain parameter meanings. The baseline for zero parameters is 4, and the description correctly focuses on the tool's purpose rather than parameter details.

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 'List safe account aliases' clearly identifies the action (list) and the resource (safe account aliases). It distinguishes this tool from sibling tools like list_mailboxes and search_emails by focusing specifically on account aliases.

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 instruction 'Call this before using an unknown alias' provides direct guidance on when to invoke this tool. It clarifies a specific use case, implying it is a prerequisite for handling unknown aliases.

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