list_credit_bundles

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

With no annotations, the description provides the key behavioral detail – that it returns each bundle's ID, credit amount, price, and description. The verb 'List' implies a read-only operation with no side effects, which is transparent enough. It does not add extra context like auth requirements or rate limits, but for a simple list operation that's acceptable.

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 two short sentences: the first states the action, the second lists the return fields. No wasted 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?

The tool is very simple with no parameters, output schema exists, and the description covers the return content. There is no missing information for an agent to invoke it correctly.

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 tool has zero parameters, so the description need not explain parameter details. The empty schema is fully covered. The baseline of 4 applies.

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 opens with 'List available credit bundles that can be purchased,' clearly identifying the action (List) and resource (credit bundles). It distinguishes from sibling tools like get_credit_balance and credits_checkout by focusing on purchasable bundles. The return fields further specify purpose.

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 context is clear: this tool is for retrieving purchasable credit bundles. It does not explicitly mention alternatives or exclusions, but the simple no-parameter nature and phrasing make the use case self-evident. However, it leaves any comparison to get_credit_balance or credits_checkout implicit.

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