search_customers

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

Beyond the readOnlyHint and openWorldHint annotations, the description adds substantial context: it specifies that cards are never returned, requires the CUSTOMERS_R permission, and clarifies the fields parameter's narrowing behavior. These are valuable behavioral details not captured by the annotations or schema.

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 three sentences, front-loaded with the core purpose, and includes essential behavioral notes without any fluff. Every sentence adds value, and the structure is easy to scan.

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 search tool with an output schema and good annotations, the description covers the key aspects: search keys, a permission requirement, a critical exclusion (cards), and field projection. It lacks explicit details on limit behavior and how criteria combine, but overall is sufficiently comprehensive for an agent to invoke it effectively.

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 explains the semantics of query (full name), phone, email, and fields (including the allowlist constraint), which is meaningful given zero schema description coverage. However, the limit parameter is not described, and the relationship between multiple search criteria (AND vs OR) is ambiguous, keeping it from a perfect 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 customers by full name, phone, or email, which is a specific verb and resource. It also differentiates from siblings like get_customer by emphasizing it is a search operation rather than a single-record fetch.

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 explicit guidance is provided on when to use this tool versus alternatives such as get_customer, which might be used when a customer ID is already known. The description explains the search criteria but does not offer contextual recommendations or exclusions.

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