Get attested price (Rubric Protocol)

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

With no annotations, the description carries the full burden and does so: it discloses the x402 pay-per-call pricing, auto pay-and-retry on the 402, the need for a funded RUBRIC_MCP_PAYER_KEY, post-quantum ML-DSA-65 signature, HCS anchoring, and permanent verifiability of attestationId. It also explains what the optional proof and at modes add and cost, going well beyond the schema.

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?

It is reasonably front-loaded, opening with what the tool does and following with payment and trust mechanics. At three long sentences it is dense, but every clause carries information an agent needs to invoke the tool correctly.

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 3-parameter tool with no output schema and no annotations, the description fills the gap completely: it covers what is returned, the payment/auth requirements, the differentiating verification guarantee, and the effect of each optional parameter.

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%, so the schema already documents symbol, proof, and at clearly. The description restates the mutually exclusive nature of proof and at and their price differences, which is mildly useful context but adds little beyond the schema's own field descriptions.

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+resource: 'Live spot price for a Base-mainnet asset pair ... read straight from Chainlink aggregators via eth_call'. It crisply names what is returned and contrasts with its sibling by pointing to list_attested_services for supported pairs.

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 exactly when to pay more for proof:true vs at:<ISO timestamp>, and notes the required funded payer key. It also names the sibling list_attested_services as the way to discover supported pairs, giving the agent a clear decision path.

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