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

The annotations already declare readOnlyHint=true and openWorldHint=true, covering the safety profile. The description adds that the call is 'Free' (a cost/likely rate consideration) and that it returns a version, which is modest but real value beyond the structured fields.

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 sentences, front-loaded with the core verb+resource, with zero padding. The fragment 'Free.' is terse but does carry information about cost.

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-parameter, read-only version endpoint with no output schema, the description supplies the essential fact (it returns the service version) and its cost profile. Only minor detail, such as exact return format or error behavior, is absent, which is acceptable for a trivial health probe.

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 is 4. No parameter-level gaps exist.

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 ('Read') and resource ('Agents Trust service version'), so an agent knows exactly what it retrieves. It does not reference the sibling tools (recommend, inspect, receipt), but their domains are distinct enough that confusion is unlikely.

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: a version/health read is naturally used to verify service availability or version compatibility. There is no explicit when-to-use or when-not-to-use guidance and no named alternative, though 'Free' hints that cost is not a concern.

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 provides rich behavioral context that goes far beyond the annotations. It explains the financial constraints (1% fee, 0.001 USDC floor), the authorization requirements (owner opt-in, shared process limits), which are essential for an agent to execute this stateful operation safely.

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 very dense and heavily weighted toward policy and financial disclosure. While all content is necessary, the sentence structure is complex and requires the agent to parse multiple nested constraints (fee, floor, opt-in, shared authorization) in a single block of text.

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?

Despite lacking an output schema, the description successfully covers the 'cost' and 'governance' aspects of the tool. By detailing the fee structure and authorization prerequisites, it provides almost all necessary context for a complex operation.

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 description adds crucial domain knowledge to the 'url' parameter, specifying that 'API rejects private URLs before payment.' This nuance is vital and not captured in the schema, significantly improving parameter understanding.

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 clearly defines the purpose: reading stored evidence for a specific endpoint URL without initiating a new call or payment. It distinguishes itself from siblings like 'recommend' or 'receipt' by focusing specifically on the act of 'inspect[ting]' and quoting.

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?

While it doesn't provide a direct 'if-then' usage guide, it strongly implies usage by detailing the payment mechanism, fee structure (1% floor), and the need for owner opt-in. This gives the AI sufficient context on when the operation is applicable.

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 declare readOnlyHint=true and openWorldHint=true, so the safety and external-lookup profile is covered structurally. The description adds the useful detail that the lookup is free (no cost/rate concern), but says nothing about behavior when the payment attempt ID is unknown, whether settlement records can be pending, or what data is returned.

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 sentences, front-loaded with the action and resource; nothing is padded. The trailing 'Free.' is a fragment, but it carries non-obvious information about cost, so it earns its place.

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 single-parameter read-only lookup with no output schema, an agent still lacks any indication of what a 'payment settlement' result contains (status, amount, timestamps) or how a missing/invalid attempt ID is surfaced. Annotations cover the safety profile, so this is adequate but not complete.

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%: the schema only declares a UUID-format string named payment_attempt_id, with no prose. The description clarifies that this ID refers to a payment attempt and is the lookup key, which adds meaning beyond the field name. It does not explain where the agent should obtain such an ID, but for a single required parameter the gap is modest.

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 and resource ('Look up payment settlement') plus the lookup key ('by payment attempt ID'), which is far more informative than the bare name 'receipt'. It does not distinguish itself from the listed siblings (recommend, inspect, health), but those appear to operate on entirely different resources, so the risk of confusion is low.

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?

There is no explicit statement of when to use this tool versus alternatives, nor any prerequisites or exclusions. Usage is only implied by the object of the lookup; the agent must infer that this is the settlement-lookup tool and not, for example, a payment-status tool.

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?

Without this sentence the agent would assume a plain lookup; instead it learns that payment may occur, that it requires owner opt-in, that it consumes the process's single authorization irreversibly, and that there is a USDC cap. That is strong non-obvious disclosure consistent with readOnlyHint=false and idempotentHint=false. It stops short of saying what happens if opt-in is missing or the fee exceeds the limit.

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 tight sentences with the discovery capability front-loaded and the payment/auth constraint second. Dense but every clause adds information; 'up to the configured USDC limit' is the only mildly vague phrasing.

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?

There is no output schema, so the description must convey return shape — 'URLs, prices and call details' does so only at a high level. The payment and authorization consequences are well covered, but the six-parameter input surface is largely unaddressed, leaving the agent guessing on most call arguments.

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 17% — five of six parameters (need, live, view, chain, limit) have no schema description and no mention in the prose. The description hints at output richness ('URLs, prices, call details') which loosely relates to the view enum, but it never explains need format, the chain identifier pattern, the limit cap of 5, or what 'live: 1' does. It does not compensate for the coverage gap.

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 gives a clear verb+resource: it finds APIs matching a stated need and returns URLs, prices, and call details. This is much more specific than the opaque name 'recommend'. It does not, however, contrast itself against its siblings (inspect, receipt, health), so the agent must infer the boundary.

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 your task' implies the general context but states no when-to-use or when-not-to-use conditions. Nothing tells the agent how this differs from 'inspect' (presumably for a single already-known API) or when to prefer receipt/health.

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