calculate_x402_topup

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

Discloses pricing model (free duration, $4/$8 per GB). Does not explicitly state read-only nature, return format, or error conditions. Without annotations, more transparency would be beneficial.

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?

Two sentences, zero waste. Front-loaded with purpose, efficient delivery of key pricing detail.

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?

Lacks output format description, which is crucial for a calculation tool. Also missing prerequisites and error handling. Adequate but not fully comprehensive for use without additional context.

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?

Schema already covers parameters with descriptions (100% coverage). Description adds pricing context but does not deepen understanding of individual parameters beyond schema.

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?

Description clearly states it calculates top-up cost for additional traffic/duration. Distinct from sibling tools like topup_x402_session (which likely performs the top-up) and calculate_price (for new purchases).

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?

Implied usage: use before performing actual top-up with topup_x402_session. However, no explicit when-to-use, when-not-to-use, or mention of alternatives. Agent must infer from context.

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