Get credit balance

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

No annotations are provided, so the description must convey behavior. It states the balance is 'current' and in USD, implying a read-only operation, but it does not disclose potential side effects, authentication requirements, or return format. For a simple getter, this is adequate but not rich enough to fully compensate for missing annotations.

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 sentences, front-loaded with the core purpose and followed by one contextual remark. Every word earns its place; no redundancy or filler.

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, no output schema), the description is sufficiently complete. It explains the balance's units and its role as the only usage limit, which provides meaningful context for why an agent would call this tool. Missing minor details like response shape or error cases, but those are not critical for a zero-param read-only getter.

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 correctly omits parameter details. The baseline for 0 params is 4, and the description adds no unnecessary information, keeping the tool simple and understandable.

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 uses a specific verb ('get') with a clear resource ('prepaid credit balance in USD'), which fully defines the tool's purpose. It also adds a scoping detail ('Balance is the only usage limit') that distinguishes it from the sibling tools, which are all about different actions like chat, scraping, or image generation.

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 implies the tool's usage (checking the balance before using other tools) but does not explicitly state when to use it versus alternatives. It mentions that balance is the only usage limit, which suggests the context, but lacks a direct 'Use this when...' statement. No exclusions or alternative tool names are provided.

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