Search Contacts by Email Addresses

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

The description lacks behavioral details such as expected return format, handling of unmatched emails, pagination, or authentication requirements. For a tool with no annotations, this leaves significant gaps for the agent.

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 concise but lacks structure. While it is appropriately short for a simple tool, it could benefit from front-loading key details like output or limitations.

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 simplicity (single parameter, no annotations, no output schema), the description is incomplete. It omits information on return values, error cases, and behavior when no matches are found.

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 100%, with the 'emails' parameter having a clear description. The tool description adds no additional semantic value beyond what the schema already provides, earning the baseline score.

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 for contacts by email addresses, specifying both the resource ('contacts') and the search criterion ('email addresses'). It effectively distinguishes from sibling tools like 'search_contacts' and 'list_contacts'.

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?

No guidance is provided on when to use this tool versus alternatives such as 'search_contacts' or 'list_contacts'. There is no mention of best use cases or when to avoid using it.

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