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

Annotations already indicate idempotent, non-read-only, non-destructive behavior. The description adds critical context beyond that: the tool is paid, costs $0.25, and requires x402 payment on specific networks. This is valuable because an agent must know a financial charge is incurred.

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 short, but the opening sentence 'Agents pay for work and prove what happened.' is vague and partly repeats the payment information in later sentences. The useful endpoint and cost details could be more tightly front-loaded.

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?

For a paid tool with two required parameters and zero schema documentation, this description is incomplete: it omits the meaning of both parameters and provides no usage scenario. Payment details are useful, but the tool is not safely invocable without parameter semantics.

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 description coverage is 0% and the description names neither parameter. The required fields 'url' and 'idempotency_key' are left unexplained, so an agent cannot determine what URL to supply or how idempotency is expected to work.

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 names an action ('prove what happened') and a paid POST endpoint, but 'work' and 'what happened' are vague. It never explicitly says this tool returns compute history, despite the title, and does not distinguish itself from the sibling compute_history.

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?

It explains that the tool is monetized via x402 and gives the endpoint and cost, but gives no guidance on when to use this tool versus alternatives like compute_history or trust_report. There are no selection criteria, exclusions, or alternative suggestions.

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