Pounds to kilograms

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

With no annotations, the description carries the full burden of behavioral disclosure. It adds one useful note about page content not being stored, but omits network side effects, redirect handling, failure modes, and the purpose of the json and zone parameters.

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 primary function and no filler. The main action is immediately clear and the additional privacy note is compact.

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?

The description is inadequate for a 4-parameter tool: it only addresses the url behavior, leaves json and zone unexplained, and provides no usage guidance, side-effect disclosure, or output detail. This is a significant completeness gap for an agent trying to decide how to call it.

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 baseline is 3. The description itself does not add meaning beyond the schema and completely ignores the json and zone parameters, making the parameter list feel inconsistent with the stated URL-only purpose.

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 has a clear verb and resource: it returns host, scheme, and HTTP status for a URL. It is specific enough to understand the core action, though it does not explicitly distinguish itself from sibling tools like normalize-url or status-catalog.

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 guidance about when to use this tool versus alternatives such as normalize-url or validate-json. The only extra note ('Page content is not stored') is a privacy statement, not a usage condition.

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 one meaningful behavioral disclosure: 'No identifiers are retained,' which informs the agent about privacy and data handling. However, with no annotations provided, the description carries the full burden of behavioral disclosure and does not state whether the operation is read-only, whether any external calls are made, or what side effects might occur.

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 concise at two sentences, front-loaded with the primary purpose and followed by a relevant privacy note. There is no wasted wording, though the brevity leaves other dimensions under-specified.

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 annotations, no output schema, and a terse description, the agent cannot determine what the classification output looks like, what input combination to provide, or how the four unrelated parameters are used. The description lacks sufficient context for correct invocation, especially given the presence of multiple sibling tools with overlapping input domains.

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 all four parameters adequately. The description adds no parameter-specific meaning beyond that, which meets the baseline but does not enrich the agent's understanding of how each parameter factors into the classification.

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 clear verb and resource: 'Show how this request is classified.' However, it does not explain what 'classified' means or what classification dimensions are involved, and it does not differentiate from the sibling tools (e.g., validate-json, normalize-url). The connection between the tool name 'compatibility' and 'classified' is also left unexplained.

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 guidance on when to use this tool versus the sibling tools, and no conditions or exclusions are given. The phrase 'Show how this request is classified' implies a classification use case, but it is vague and does not clarify which of the four heterogeneous parameters (url, host, json, zone) constitutes 'this request' or when each is appropriate.

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 provided, the description carries the full burden. It does disclose that WHOIS/ownership data is excluded, which is a useful behavioral constraint, but it says nothing about return format, error behavior, network activity, or how the json/zone/url parameters behave. The 'discarded after the check' behavior appears only in the schema, not in the description.

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 single sentence is concise, front-loads the core action, and contains no filler. It is too terse for the tool's four-parameter, multi-behavior surface, but as a simple statement it is efficient.

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?

The tool has 4 optional parameters, no output schema, and no annotations, yet the description only covers hostname splitting. It omits return values, valid parameter combinations, and how the url/json/zone parameters relate to the tool's behavior, leaving an agent with significant ambiguity about correct invocation.

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 baseline is 3 and the schema already documents each parameter. The description itself adds no parameter-level guidance, and the mismatch between the 'split hostname' purpose and the unrelated json/zone parameters creates ambiguity about which parameter should be used for which operation.

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 verb and resource: 'Split a hostname into labels' and adds a clear negative scope, 'without WHOIS or ownership data.' However, it does not mention the URL normalization, JSON validation, or timezone operations suggested by the input schema, so it only partially represents the tool's surface.

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 explicit when-to-use guidance or alternative tools are named. The phrase 'without WHOIS or ownership data' implies the tool is not for ownership lookups, but the agent gets no direction on when to choose this tool over siblings or which parameter combinations to use.

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 of behavioral disclosure, and it reveals almost nothing: no mention of what the tool returns, whether it validates or lists, or why the schema accepts a URL, host, or JSON text. The behavior is effectively undisclosed.

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 short sentence, but brevity here is under-specification rather than conciseness. It front-loads the resource but omits any verb, behavior, or usage instruction, so the sentence does not earn its place as a complete definition.

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 tool with 4 optional parameters, no output schema, and no annotations, the description should clarify call shape and return value; it does neither. The discrepancy between the tool's timezone purpose and the url/host/json parameters is never resolved, making the definition inadequate for safe invocation.

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 baseline is 3; every parameter already has a description. The tool description adds no parameter meaning. It also fails to clarify that only 'zone' plausibly relates to the stated purpose, leaving the url/host/json params confusingly unexplained.

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 identifies a specific resource ('Common IANA timezone names for clock calls'), but it is a noun phrase with no verb, so it never states what the tool actually does (list zones? validate a zone?). The mismatch between this purpose and schema parameters like url/host/json further muddles what the tool is for, though it does loosely distinguish itself from the citation sibling.

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 clock calls' gives only a faint hint of context and no guidance on when to use this tool versus the sibling 'citation' or any alternatives. There are no when-to-use, when-not-to-use, or prerequisite statements.

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 provided, the description carries the full burden of behavioral disclosure. It only mentions fetching and returning group counts, but does not disclose network behavior, error handling, rate limits, or what happens if the robots.txt is inaccessible. It also fails to mention that the schema includes unrelated parameters like json and zone, creating confusion about actual 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?

The description is a single, front-loaded sentence with no redundant words. It efficiently conveys the core function and output constraint.

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 annotations and output schema, the description is insufficiently complete. It does not explain how to invoke the tool with the correct parameter, what the return structure will be beyond 'group counts', or how to handle the seemingly extraneous json/zone parameters. An agent would struggle to use this tool correctly.

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?

Although schema description coverage is 100%, the description does not map the robots.txt fetching operation to any specific parameter. The schema's url description ('HTTPS URL to normalize or cite') does not indicate it should be a robots.txt URL, and the json/zone parameters seem unrelated to the stated purpose. The description adds no clarifying meaning, leaving the agent with a disconnect between purpose and input 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 'Fetch a public robots.txt and return group counts only' states a specific verb, resource, and output. It clearly distinguishes this tool from sibling tools like citation, normalize-zone, and validate-json, which have different purposes.

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 guidance is provided about when to use this tool vs alternatives. It does not mention any exclusions, prerequisites, or conditions under which another sibling tool would be preferable. The agent is left to infer usage from the name and short description.

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 must carry the safety and behavior burden, but it only states a ratio of units. It fails to disclose side effects, prerequisites, return format, or the fact that the declared parameters appear unrelated to the advertised conversion.

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 words is under-specification, not conciseness; there is no operational sentence or front-loaded guidance. A conversion tool with an unrelated schema needs substantially more structure.

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 4-parameter tool with no output schema, this definition is completely inadequate. The description does not reconcile the unit-conversion claim with the URL/timezone/JSON parameters, so a correct invocation is impossible to determine reliably.

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?

Although the schema descriptions are individually clear and coverage is 100%, the parameters (url, host, json, zone) do not support a pounds-to-kilograms operation. The description adds no mapping between parameters and the conversion, so an agent cannot know what to pass.

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 phrase 'Pounds to kilograms' is essentially a restatement of the tool name and lacks a verb or action. It does not explain what the tool does with the four input fields (url, host, json, zone), so the stated purpose is both under-specified and misleading.

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 guidance on when to use this tool or which sibling to prefer. Worse, the description suggests a unit-conversion use case while the schema points to URL/timezone/JSON operations, so following the description would mislead an agent.

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 of behavioral disclosure. It does add one useful behavioral trait — 'Query and fragment are dropped' — but it omits any mention of the json discard behavior beyond what the schema already states, and it gives no indication of return format or side effects. Minimal but non-zero value.

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 with the key behavioral constraint ('Query and fragment are dropped') front-loaded. No filler or redundancy, though the brevity contributes to the completeness gap elsewhere.

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?

The tool has four parameters, no output schema, and no annotations, so the description must do substantial explanatory work. It only covers the URL case, ignores the json and zone parameters entirely, and never clarifies what 'host' means as an input. An agent cannot confidently call this tool for the non-URL behaviors the schema suggests.

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 each parameter. The description adds value for the url parameter by explaining that query and fragment are dropped, but it adds no meaning for host, json, or zone. Baseline 3 is appropriate.

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 ('Return origin, host, and path for a URL') and clearly scopes the URL case, but the input schema exposes three unrelated parameters (host, json, zone) that the description never mentions. This makes the tool's actual scope ambiguous and risks misleading an agent into thinking URL normalization is the only behavior.

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 guidance is provided on when to use this tool, what inputs are appropriate for which behavior, or how it relates to alternative tools. The description's silence about the json and zone parameters leaves the agent without direction on whether those are valid use cases.

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?

No annotations are provided, so the description carries the full burden of disclosing behavior—but it discloses none. It does not state whether the tool validates, transforms, checks, or returns status codes, nor what side effects (e.g., external requests) might occur despite the seemingly read-only parameters.

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 only five words, but extreme brevity here is under-specification rather than conciseness. It conveys almost no actionable information, and there is no structured front-loading of key facts.

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 tool with 4 parameters, no annotations, no output schema, and no behavior explanation, the description is wholly inadequate. An agent cannot determine what action to take, what the tool returns, or how the parameters relate to the catalog.

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%, meaning each of the four parameters has a one-line explanation (e.g., 'HTTPS URL to normalize or cite', 'JSON text to validate; discarded after the check'). Per the baseline rule for high coverage, a score of 3 is appropriate, though the description fails to connect these parameters to the stated 'catalog' purpose.

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, 'Short catalog of common HTTP status codes,' is a noun phrase that essentially restates the tool name 'status-catalog.' It lacks a specific verb or resource indicating what the tool actually does with the provided inputs (url, host, json, zone), and does not distinguish itself from siblings like 'citation' or 'compatibility.'

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 guidance on when to use this tool instead of its siblings. No context is provided about typical use cases, prerequisites, or situations where this tool would be preferred.

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?

No annotations are provided, so the description carries the full behavioral disclosure burden. It states the tool shows the current time but does not reveal output format, behavior for invalid zones, or how it handles the non-zone parameters. The schema includes url, host, and json fields that appear unrelated, and the description does not clarify that these are irrelevant or ignored.

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 with no filler. Every word contributes to stating the tool's core purpose. It is as concise as possible while remaining informative at a high level.

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 tool with four optional parameters and no output schema or annotations, this description is critically incomplete. It never explains which parameter to populate, what the response looks like, or why url, host, and json appear in the schema. An agent would struggle to invoke this tool correctly without additional context.

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?

Although schema description coverage is 100%, the description only aligns with the zone parameter and gives no semantic link to url, host, or json. An agent cannot determine whether those parameters are required, optional, or unrelated to the timezone lookup. The schema descriptions are individually clear, but the tool description fails to resolve the apparent mismatch.

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 phrase 'Current time in a named IANA timezone' identifies the tool's function and resource clearly, indicating that it returns the current time for a zone. It lacks an explicit action verb like 'gets' or 'returns,' but the intent is unambiguous. It slightly distinguishes from a tool like utc-time by focusing on named IANA zones.

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 description gives no guidance on when to use this tool versus alternatives, nor does it mention prerequisites or exclusions. With sibling tools such as utc-time and validate-json, an agent is left to infer when timezone is appropriate. There is no explicit 'use when' or 'use instead' information.

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?

No annotations are provided, so the description carries the burden of behavioral disclosure. It states the output is a UTC timestamp, but it does not clarify the format, whether it accepts parameters, or how the listed parameters (url, host, json, zone) relate to the output. The mismatch between the description and the schema parameters is a notable gap.

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, concise sentence that is easy to parse. It front-loads the core purpose without any wasted words, though it omits any context about the unrelated parameters listed in the schema.

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?

The tool is simple (zero required params, no output schema), but the description is incomplete given the schema shows four irrelevant parameters. The agent cannot tell whether the tool actually ignores these parameters, uses them for something undocumented, or if the schema is a mistake. A simple tool should have a description that resolves this ambiguity.

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 schema description coverage is 100%, with each parameter having a clear description in the schema. However, none of these parameters logically relate to 'Current UTC timestamp' — they seem copied from other tools. The description adds no meaning to the parameters, but the schema itself is complete, so the agent can at least understand the parameter types.

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 'Current UTC timestamp' uses a specific verb and resource, clearly indicating the tool returns the current UTC time. It is distinct from siblings like citation or domain-shape, though it does not explicitly distinguish itself from any time-related sibling.

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 description implies the tool is for getting the current UTC time, but it does not state when to use it versus alternatives or mention any prerequisites. The input schema includes four unrelated parameters (url, host, json, zone) with no required fields, which creates ambiguity about how the tool is actually invoked.

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?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It does add one non-obvious and valuable trait — 'The body is discarded' — which indicates the input is not retained. But it omits what happens on invalid JSON (error vs false return), the result/return format, and whether the operation has side effects beyond discarding the body.

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 with the purpose front-loaded and zero filler. The second sentence earns its place by disclosing the discard behavior, which an agent would not otherwise know. The under-specification is a completeness concern, not a structure concern.

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 tool with no annotations and no output schema, the description is minimal. An agent cannot determine what result indicates validity, which parameter to populate ('body' vs 'json'), or whether the unrelated schema parameters matter. The 'discarded' note is the only behavioral context provided, leaving the definition incomplete for reliable invocation.

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 baseline is 3, but the description adds no parameter-level meaning and even introduces ambiguity by calling the input 'a body' instead of the schema's 'json' parameter. More problematic, the schema contains three unrelated optional parameters (url, host, zone) that clearly belong to sibling tools, and the description does nothing to clarify that only 'json' is relevant for validation.

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 ('Check') and resource (a body/JSON), clearly identifying this as a JSON validation operation. The sibling tools (normalize-url, timezone, lb-to-kg, etc.) are all distinct operations, so the purpose is easily distinguishable. However, the description says 'a body' while the schema's relevant parameter is named 'json', creating a mild mapping ambiguity, and it never states what happens when validation fails.

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 guidance on when to use this tool versus alternatives. The description provides no context, prerequisites, exclusions, or mention of sibling tools. An agent can only infer by name and sibling list that this is the JSON-validation tool; nothing in the text says 'use this when you need to verify JSON syntax' or warns when not to use it.

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