list_customers

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

With no annotations provided, the description carries the burden of disclosing behavior. It clearly explains the cursor-based pagination pattern and how to continue fetching results, which is a non-obvious behavioral trait. It doesn't explicitly state that it's a read-only operation, but 'list' implies safety.

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 exactly two sentences: the first states the purpose and filters, the second explains pagination. It is front-loaded, efficient, and contains no unnecessary words.

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?

Despite having 6 optional parameters and no output schema, the description addresses the most critical non-obvious detail: cursor pagination. It doesn't describe the customer object structure, but that is a minor omission given the tool's self-explanatory nature and the comprehensive schema parameter descriptions.

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 each parameter having a detailed description (e.g., since_id: 'Return customers with ID greater than this value (cursor pagination)'). The description adds no additional meaning beyond reinforcing the cursor loop, so the baseline of 3 is appropriate.

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 'List customers with optional filters', identifying the specific action and resource. It distinguishes itself from siblings like get_customer (single customer), search_customers (search), and list_customer_addresses (addresses). The verb 'list' plus resource 'customers' is unambiguous.

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 pagination guidance: 'If has_more=true, call again with next_since_id.' This tells the agent exactly how to handle multi-page responses. However, it does not explicitly state when to use this tool over alternatives like search_customers, so it lacks exclusions.

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