FOXIFY Agent Authority + Payment Preflight

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so the safety profile is covered structurally. The description's only added claim is 'Free', which hints at a pricing model but never explains it, and 'machine-payable authority' is unexplained jargon that leaves the actual behavior opaque.

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 short sentence with no padding, so it is certainly concise. But brevity here comes from under-specification rather than economy — there is no front-loaded statement of what the agent actually gets back.

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 zero parameters and no output schema, the description is the only source of information about the return value, and it never says what the 'metadata' contains. For a discovery/info tool where the payload is the entire product, that gap is significant.

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, so there is nothing for the description to disambiguate; the baseline of 4 applies. The empty schema is fully consistent with the description.

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 sentence largely restates the title: 'FOXIFY Preflight Info' becomes 'metadata for FOXIFY ... preflight tools.' There is no specific verb or resource ('metadata' about what?) and nothing distinguishes it from verify_agent_action_intent or verify_agent_payment_intent beyond the vague word 'preflight'.

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?

No statement of when to call this versus the two sibling verify_* tools, no prerequisites, and no mention of whether it should be called before verification. The only hint is the word 'preflight', which implies ordering but is never made explicit.

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

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

Annotations already disclose that the tool is not read-only, is open-world, is not idempotent, and is not destructive. The description adds important behavioral context by stating the $0.25 USDC cost on Base and the authority lifetime, retry, and postcondition binding scope. It stops short of describing the response shape or failure behavior, but meaningfully goes beyond the annotations.

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?

The description is two dense, front-loaded sentences with no wasted text. It leads with the core purpose and pricing, then enumerates the binding scope.

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?

This is a complex paid verification tool with no output schema and eight parameters, so the description should do more to explain the resulting decision or workflow. It covers purpose, cost, and binding scope, and annotations cover safety hints, but return semantics and operational prerequisites remain unclear.

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 low at 38%, so the description must compensate. It does map several top-level concepts to parameters (subject, action fields, authority lifetime, retries, postcondition), but it omits key details for action_id, nonce, and the allowed-tools/operations/targets lists.

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 states a specific verification/preflight purpose for consequential agent tool calls and enumerates what it binds: subject, tool, operation, target, parameters, authority lifetime, retries, and postconditions. It is clear what the tool does, though it does not explicitly differentiate itself from the sibling verify_agent_payment_intent.

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 phrase 'for consequential agent tool calls' implies when to use the tool, but there is no explicit when-not guidance or routing to alternatives such as verify_agent_payment_intent or foxify_preflight_info. Usage is inferable but not fully specified.

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

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

The description adds genuinely non-structured information: the call costs $0.05 USDC on Base, and it consumes an anti-replay nonce, which explains the non-idempotent and non-readOnly annotations. It does not say what happens on a failed verification or whether the nonce is burned on failure, which is material for a paid, non-idempotent 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 dense sentences with no filler; the purpose and the enforcement scope are front-loaded before the cost note, which is exactly the ordering 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?

For a verification tool with no output schema, the description never indicates what a result looks like (pass/fail verdict, reason codes, whether a signed receipt is returned). Combined with 43% schema coverage and a nested six-required-parameter payload, an agent can decide when to call it but not how to interpret the response.

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 coverage is only 43%, so the description must compensate – and it does by mapping the enumerated checks onto parameter groups (authorization→mandate, payment.amount→amount, payment.recipient/destination, merchant, expires_at→expiry, nonce→replay risk). It still leaves nested optional fields such as human_confirmed and allowed_domains without meaning.

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 states a specific verb ('checks') and resource ('payment intent' preflight), and enumerates the exact facets verified (mandate, amount, destination, merchant, expiry, replay risk). Differentiation from siblings is only implicit – 'before an autonomous payment executes' distinguishes it from verify_agent_action_intent, but the sibling is never named.

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?

'Paid transaction preflight ... before an autonomous payment executes' gives a clear triggering context and sequencing constraint. It stops short of naming alternatives (e.g., when to use verify_agent_action_intent instead) or stating exclusions, so it does not reach a 5.

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