get_user_by_email

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

With no annotations, the description should disclose behavioral traits. It states the basic read operation and return format but omits permissions, rate limits, or behavior on missing input. It does not contradict any annotations.

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 short and front-loaded with the core purpose. It uses a clear param listing format, but could be more efficiently structured. Every sentence serves a purpose without unnecessary 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 1-param lookup with an output schema present, the description covers input, return format, and basic behavior. It is adequate, but could benefit from mentioning exact match fallback or error handling nuance.

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 description's 'email (str, required)' merely echoes the schema. Schema coverage is 0%, and the description adds only the phrase 'exact match preferred', which provides minimal extra meaning beyond the schema definition.

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 finds a user by email, which is specific and distinct from siblings like get_user_profile or search_user. The phrase 'exact match preferred' adds nuance, but it doesn't explicitly differentiate from other search tools.

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 no explicit guidance on when to use this tool versus alternatives like search_user or get_user_profile. It only implies exact match usage, but lacks when-not-to-use instructions for a multi-tool context.

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