Signed attestation of an agent's spend (PAID $0.50)

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

Annotations already declare the safety profile (readOnly=false, destructive=false, openWorld=true, idempotent=false). The description adds genuinely non-derivable context — the $0.50 x402/USDC cost and the POST route on eip155:8453 — but says nothing about what gets written to the ledger, whether the attestation is permanent, or whether payment precedes or follows the call.

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 short lines with the cost and route front-loaded; nothing is padded. However, the entire first clause is a verbatim restatement of the title, so a quarter of the text is redundant rather than informational.

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?

An output schema exists, so return values need not be described. But for a paid, non-idempotent mutation tool with a nested object parameter at 0% schema coverage, the description leaves the agent unable to construct a valid call or understand the payment flow.

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% for three parameters, including a required agent_id and two structured params (period object, entries array). The description contributes no meaning at all for these — not the expected period shape, entry fields, or whether entries seed the attestation or are derived.

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: a signed attestation of an agent's spend ledger, with the price inline. It is distinguishable from siblings like v1_readiness_attest or v1_uptime_attest by the spend-ledger scope, though it never explicitly contrasts with v1_spend_anomaly or the treasury tools.

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?

The only guidance is the transport route and payment rail. There is no indication of when an agent should call this versus v1_spend_anomaly, v1_audit_evidence_package, or the treasury report tools, and no preconditions such as required entries or period alignment.

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