search_clients_by_phone

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

No annotations exist, so the description carries full burden. It discloses prefix-match logic, page limit of 50, and lack of pagination details like sorting. While adequate for a read-heavy search, it omits whether results are ordered or what fields are returned (though output schema may cover this).

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?

Three sentences with no fluff. The first sentence fronts the main purpose and constraints. The second provides a usage scenario. The third explains the design rationale. Every sentence adds value.

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 low complexity (2 params, no annotations, output schema present), the description covers the core behavior and use case well. It lacks details on result ordering or handling multiple matches, but is complete enough for most scenarios.

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?

With 0% schema description coverage, the description must explain parameters. It explains 'phone' (prefix match) but does not explicitly describe the 'page' parameter, only implying pagination via 'up to 50 per page'. The baseline for low coverage is low, and the description only partially compensates.

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 'Find clients by phone number (prefix match, up to 50 per page).' This specifies the verb (find), resource (clients), and key constraints (prefix match, page limit). The tool name and sibling search_clients_by_email provide implicit differentiation.

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 explicitly states when to use this tool: 'when a prospect's email is unknown (e.g. a phone call comes in) to find their existing record before creating a new lead.' It also explains the rationale for prefix matching, giving agents clear context for invocation.

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