set_default_user

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

With no annotations provided, the description carries the full burden. It discloses that this sets a persistent default affecting 'all authentication and directory searches,' which is useful behavioral context. However, it doesn't mention security implications, permission requirements, or whether the change is reversible, leaving gaps for a mutation tool.

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 perfectly concise with two sentences that are front-loaded and waste no words. The first sentence states the purpose and benefit, while the second explains the scope of effect, with every element earning its place.

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?

Given the tool's moderate complexity (mutation with security implications), no annotations, and no output schema, the description is adequate but incomplete. It covers the core purpose and usage context but lacks details on behavioral traits like error handling or return values, leaving room for improvement.

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%, so the schema already documents the single parameter 'userEmail' as 'Your email address to set as the default user.' The description adds no additional parameter semantics beyond this, meeting the baseline for high schema coverage without extra value.

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's purpose with a specific verb ('Set') and resource ('default user email'), explaining it configures persistent authentication settings. It distinguishes from siblings like 'login' (temporary session) and 'check_authentication' (verification) by focusing on default configuration.

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 provides clear context for when to use this tool: 'so you don't need to provide it every time' and 'used for all authentication and directory searches.' However, it doesn't explicitly state when NOT to use it or name alternatives like 'login' for temporary sessions, missing full sibling differentiation.

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