q402_balance

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly states 'Read-only', discloses conditional behavior when both keys are set, and details the trial-credit output (days-left and credits-remaining). It also adds external links for further context, which is useful but not exhaustive (e.g., no mention of error handling or empty-key scenarios).

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 front-loaded with the core purpose ('Verify the configured API key(s) and report...') followed by conditionals and links. Every sentence adds value: read-only flag, dual-key behavior, trial details, and dashboard pointer. It is moderately sized, not overly verbose, and despite being a bit longer than strictly necessary, it remains tightly structured.

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 zero annotations, no output schema, and no parameters, the description provides a strong level of completeness: it explains the tool's read-only nature, conditional outputs, and points to external resources for additional needs. The only notable gap is the lack of explicit handling for cases where no keys are configured, but for a verification tool with this scope, the coverage is solid.

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, and the schema coverage is trivially 100% with an empty object. The description correctly does not attempt to explain parameters, and instead focuses on behavioral context. Baseline 4 for zero-parameter tools is appropriate, and the description adds relevant context about the keys involved without needing to document parameter syntax.

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 a specific verb 'Verify' and resource 'API key(s)', and clearly states it reports each one's plan tier (live vs sandbox vs trial). This distinguishes it from sibling tools like q402_wallet_status, which focus on wallet state rather than API key plan status. The read-only declaration and trial-specific details further clarify the tool's exact 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 description provides clear usage context: it explains the dual-key scenario and when to use this tool to show both trial and paid credits. It also explicitly points to the dashboard for per-chain gas tank balances, giving a when-not-to-use direction. However, it does not name any sibling tools as alternatives, leaving a small gap in direct comparisons.

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