get_balance_tool

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

With no annotations, the description carries the full burden and does disclose two real behavioral traits: it is 'best-effort' (results may be incomplete or fail) and it needs an official API key. It does not mention rate limits or what happens on failure, but the auth and reliability caveats are substantive.

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 with the resource named first and constraints in a compact parenthetical. 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?

An output schema exists, so return values need no explanation, and the simple zero-parameter read is adequately covered by the purpose, auth requirement, and best-effort caveat. Only the concrete meaning of 'best-effort' (stale data? partial failure?) is left undefined.

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 takes zero parameters and the schema is trivially empty, so there is nothing to document; the baseline for 0 params 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?

Specific verb + resource: 'Get available credits + plan' tells the agent exactly what it returns, and no sibling tool in the list overlaps with billing/credits. The only slight dilution is the vague parenthetical qualifier, which adds caveats rather than precision.

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 states a prerequisite ('official API key required'), which is useful usage context, but it never says when to call this versus other tools or how to react to the credits/plan values. Usage is implied only.

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