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

With no annotations, the description carries the full burden. It usefully discloses the qualification rule (settled payments to 3+ distinct sellers on the newest day) and the returned fields, but says nothing about ordering, pagination beyond the limit param, origin of funds, or edge cases such as partially settled payments.

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 sentences, no filler, with the defining qualification front-loaded before the returned fields. Efficient and readable, though the second sentence is a terse noun list rather than a polished clause.

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 no output schema, the description compensates by listing the return fields (payments, USDC, categories bought, sellers paid), which is exactly what the agent needs. It is complete enough to invoke correctly for this low-complexity, single-parameter tool.

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% and there is a single optional parameter, so the schema already documents limit's default and max. The description adds no extra meaning about the parameter, matching the baseline of 3.

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 a specific resource (buyer wallets) and a precise filter criterion (x402-settled payments reaching three or more sellers on the newest day), so an agent knows exactly what set of records is produced. It lacks an explicit retrieval verb and does not name the sibling it differs from, keeping it short of a 5.

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 when-to-use or when-not-to-use guidance relative to siblings like market_today, compare, or seller. The marketing phrase 'the honest signal of an agent at work' gestures at intent but gives the agent no condition for selecting this tool over alternatives.

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?

With no annotations at all, the description carries the full behavioral burden, and it does disclose meaningful traits: every row is date-stamped with the provenance of its figures, and hosts absent from the registry are reported as 'unknown' rather than fabricated. It leaves out data freshness/latency, cost, and what a failed lookup row actually looks like, which keeps it short of a 5.

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 sentences, no filler, and the core scope (2-5 hosts, side by side) is front-loaded before the field list. The first sentence is a long comma-run of dimensions, but each clause adds a distinct comparison axis and the final two sentences cover edge cases rather than padding.

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 or annotations, so the description must stand in for return-shape information, and it does so by enumerating the compared fields and the unknown-host behavior. What is missing is minimal but real: effective host cap beyond the schema, and any notion of data freshness or retrieval latency.

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% and the single `hosts` parameter already documents the array with an example, so the baseline is 3. The description adds only marginal meaning by clarifying these are seller hosts the registry must list, but adds no format or validation detail beyond the schema.

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 concrete action ('two to five seller hosts side by side') plus an enumerated set of comparison dimensions (price range, x402 payments, payer wallets, concentration, operator group), so the resource and scope are unambiguous and clearly multi-host. It never names a sibling tool, so the contrast with single-host tools like `seller` is only implied rather than stated.

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 2-5 host range implies this is the multi-host comparison path, and the schema enforces minItems/maxItems, so an agent can infer when to reach for it. However, there is no explicit when-to-use versus `seller`, `search`, or `operator`, and no exclusions or prerequisites are given.

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?

With no annotations, the description carries the full behavioral burden. It does disclose useful semantics — a static snapshot tied to the 'newest published day' rather than a live query — and enumerates the returned dimensions. It omits return shape, units, timestamp/freshness guarantees, and any error or caching behavior.

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 front-loaded sentence that begins with the resource and scope before enumerating metrics; no filler sentences. The trailing enumeration is slightly run-on, which keeps it from a 5, but every element is informative.

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 no output schema and no annotations, the description must justify trust on its own, and the metric list partially stands in for a return schema. Still missing are the meaning of the metrics, any freshness/timestamp guarantee, and output structure, which for a schema-less read tool is a real gap.

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 the baseline is 4 under the scoring rules; there is nothing for the description to clarify. It appropriately does not invent parameter talk that would not apply.

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 concrete resource and scope: a snapshot of the x402 market on Base for the newest published day, enumerating the metrics returned. It does not, however, distinguish itself from siblings like agents_at_work, which the description effectively also advertises as part of the payload, leaving overlap unresolved.

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 when-to-use or when-not-to-use guidance and no mention of alternatives such as compare, search, or operator. The agent can infer it fetches a current market summary, but nothing routes it between this and the sibling tools.

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?

With no annotations, the description carries the full burden. It does disclose real behavioral traits: it aggregates across all hosts sharing a wallet and restricts results to the newest day. It says nothing about permissions, rate limits, or whether the newest day is relative to the query time, so the disclosure is partial.

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 sentences with no filler, and the returned data is front-loaded before the input instruction. The em-dash appositive is slightly convoluted and the referent of 'group' is never pinned down, costing a point.

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 one-parameter, no-output-schema tool this is close to sufficient: it states scope, aggregation, and time window, and how to address the group. It omits return shape details and what 'newest day' resolves against, which an agent would still have to discover.

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 single parameter is fully documented in the schema ('a host, or the operator's domain'), so the baseline is 3. The description adds only marginal meaning by broadening it to 'any host in the group or the group's name', which slightly reconnects 'host' and 'operator' but introduces terminology ('group') not present in the schema.

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 a specific resource (the hosts one operator runs) and the data returned (combined x402 payments and USDC on the newest day), so an agent can grasp what the tool produces. It stops short of naming or contrasting any sibling (seller, compare, market_today), so it is clear but not differentiated.

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 'Give any host in the group or the group's name' tells the caller what to pass, which implies usage, but there is no explicit when-to-use versus siblings like seller or compare. The scope of the aggregation is inferable but never stated as a selection rule.

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?

With no annotations, the description carries the burden and does disclose real behavior: matching is word-by-word and also intent-mapped into Atlas categories, and results are ranked by x402 payments on the newest day then by self-reported paid calls. It omits auth needs, pagination/caps, and rate limits, so it is informative but not complete.

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?

Three sentences, front-loaded with the purpose, then matching semantics, then ranking, then the operator note. Every sentence carries information, though the final operator clause is slightly tangential to the core search action.

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 and no annotations, so the description must carry behavior, and it covers purpose, matching rules, ranking, and that operators are also returned. It does not describe result shape (fields per seller), auth, or pagination, leaving modest gaps for a no-annotation tool.

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 100%, so both parameters are already documented (limit: default 10, max 25; query: words, a host, or the job you need done), which sets a baseline of 3. The description adds how the query is interpreted (intent into Atlas categories), but says nothing about the limit parameter beyond the schema.

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 clear verb and resource ("Find sellers that do a job") plus the matching mechanism (word-by-word plus intent into Atlas categories), and even notes it surfaces matching operators. It is distinguishable from market_today and compare, though it does not explicitly name a sibling to avoid.

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: it is the lookup entry point for finding sellers, and the example intents hint at suitable query shapes. There is no explicit when-to-use vs market_today or seller, and no stated prerequisites or exclusions.

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?

With no annotations, the description carries the full behavioral burden. It implies a read-only retrieval by describing a 'card' and history, but never states that it is safe, unauthenticated, or side-effect free, so transparency is partial.

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 a single, front-loaded sentence that packs in many return fields without waste. It is dense but appropriate for a complex tool that has no output schema, though the run-on list slightly hurts readability.

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?

Given the absence of an output schema and annotations, the description does a good job listing the expected return data. It is less complete on tool selection context—no mention of when to prefer it over compare or search—but sufficient for understanding what a call returns.

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 100% and the single 'name' parameter is fully documented in the schema. The description adds no parameter semantics beyond what the schema already provides, matching the baseline of 3.

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 ('One seller's card') and enumerates the specific data it returns, making its scope clear. However, it lacks an explicit verb and does not contrast itself with sibling tools like compare or search, so it stops short of a 5.

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 when-to-use or when-not-to-use guidance is provided. The description only describes the output content, leaving the agent to infer that this is the tool for a single seller lookup.

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