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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and external-reach are covered structurally. The description adds that the data is 'live,' implying real-time freshness rather than cached values, plus the per-chain and daily-cap dimensions, but says nothing about rate limits, staleness windows, or response shape.

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 tight sentences with the data contents front-loaded and the action cue second. No filler, no restatement of the title, nothing that fails to earn its place.

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?

With no input parameters, no output schema, and annotations covering safety, the description carries the burden of saying what comes back, and it does so adequately by listing float, availability, prices, and caps. A note on freshness or update cadence would have closed the remaining gap.

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, which is the baseline-4 case. The description still adds value by explaining the granularity of the result set ('per-chain'), telling the agent what dimensions come back without needing a chain argument.

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 the resource and enumerates its contents: 'live per-chain float, availability, prices and daily caps of the AgentGas service.' An agent can tell this is a read-only status/state lookup, distinct from the sibling order/quote/how_to_buy tools, though the verb itself is only implied rather than stated.

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?

'Check before paying' gives a usage cue tied to the ordering flow, implying this is a pre-transaction sanity check. It does not name agentgas_quote or agentgas_order as alternatives, nor state when this tool is the wrong choice, so guidance remains implied rather than explicit.

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