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

Annotations already mark this as readOnlyHint=true and openWorldHint=false, but the description adds a non-obvious behavioral fact: the call is itself billable ('Paid per call via x402 when payments are on'), which an agent could not derive from the safety annotations and which matters for call planning. It also discloses the freshness/liveness nature of the data (current usability, measured turnaround, remaining hardware budget), though it says nothing about caching, latency, or rate limits.

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?

A single dense sentence that front-loads the core purpose, with the cost caveat placed at the end where it belongs. It is slightly run-on in the middle ('whether it is usable now, its estimated price, measured turnaround, and the hardware budget'), but every clause carries information an agent needs.

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 a zero-parameter schema, an output schema documenting return shape, and annotations covering the safety profile, the description covers everything an agent needs: what it lists, what fields come back, and that the call can cost money. Nothing material is missing for correct invocation.

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 input schema declares zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description correctly implies a no-argument call returning the full backend catalog.

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 precisely — every backend the server can route to — and enumerates the concrete providers (local simulator, IonQ, IBM Quantum, Amazon Braket), so an agent knows this is a discovery/catalog call rather than a job submission. It cross-references quantum_pricing, but it doesn't explicitly distinguish itself from quantum_benchmarks, quantum_status, or quantum_hardware_job.

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?

Usage is only implied: an agent can infer this should be called to survey options before quantum_run_hardware or quantum_run_circuit. There is no explicit 'call this when you need X' or 'do not call this if Y', and no prerequisites are stated beyond the pointer to quantum_pricing for payment details.

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