get_credits

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

With no annotations provided, the description alone must convey behavioral transparency. 'Check' implies a read-only operation, but it does not explicitly state the absence of side effects, authentication requirements, or any rate limits. It provides minimal behavioral context beyond the action itself.

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?

A single, front-loaded sentence conveys both the primary purpose and the scope of information returned. Every word earns its place and there is no fluff.

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 tool's simplicity — no parameters and no output schema — the description adequately covers what the tool does and what information it provides. It is complete enough for an agent to invoke it correctly without further clarification, though it could mention the output format.

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 input schema has zero parameters, so there is nothing to document. The baseline of 4 for no params applies, and the description adds no unnecessary parameter information, which is appropriate here.

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 checks available Audible credits and membership information, using a specific verb and resource. This distinguishes it from sibling tools like search_audiobooks or get_library, which cover different content areas.

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 gives no guidance on when to use this tool versus alternatives. There are no exclusions or context cues beyond the resource name, leaving an agent to infer that it is for credit-related queries rather than library or wishlist operations.

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