refueler_capabilities

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 key behavioral facts: unauthenticated access, no cost, and that the live server state governs send behaviour. It implies a safe read but never explicitly says the call is side-effect-free or cacheable, which leaves a small gap for a tool with zero annotation coverage.

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?

Three short sentences, zero filler, with the purpose front-loaded and the usage condition immediately after. Every sentence earns its place by adding purpose, timing, or cost/auth context.

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 no-required-param, no-output-schema discovery call, the description covers what to do and when, plus auth and cost. It does not describe the shape or format of the returned payload, which an agent might want given there is no output schema, but it does enumerate the categories of data returned.

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 100% and the single 'detail' parameter is fully documented in the schema, including its enum values and that 'full' is identical in v1. The description adds no parameter-level semantics, so the baseline of 3 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?

States a specific verb (Fetch) and a concrete resource (Refueler Share service capabilities, rate card, feature flags), naming the actual payloads returned. No sibling tools exist, so no differentiation is required. An agent immediately knows what this tool yields.

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?

Clearly prescribes when to call it: 'Call this before any send to gate behaviour on live server state.' This gives a concrete precondition rather than an implied one. It does not discuss when-not to call or alternatives, but none meaningfully exist for a capability-discovery call, so the gap is minor.

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