JWT header shape, payload discarded

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

With no annotations present, the description carries the behavioral disclosure burden. It does add a meaningful non-storage guarantee: 'Page content is not stored.' However, it does not disclose whether the tool makes network requests, how failures are handled, or any other side-effect profile, leaving notable gaps.

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 short sentences with no redundancy. The primary result is front-loaded, and the additional privacy-relevant note about not storing page content earns its place. This is appropriately concise and well structured.

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 and no output schema, yet the description only addresses URL-citation behavior. The presence of json and zone parameters, alongside siblings like validate-json and timezone, suggests additional modes or behaviors that the description omits. An agent could not confidently determine what happens when those parameters are supplied.

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 description need not repeat parameter meanings. The phrase 'for a URL' weakly maps to the url parameter, but the description adds no semantic context for host, json, or zone beyond what the schema already provides.

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 action and resource: 'Return host, scheme, and HTTP status for a URL.' This is clear at the sentence level and implies a distinction from siblings like normalize-url. However, the description does not mention or reconcile the additional schema parameters (host, json, zone), so the overall tool purpose is only partially 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?

There is no explicit guidance on when to use this tool versus alternatives such as normalize-url, status-catalog, validate-json, or timezone. The description implies URL-related use, but it never states exclusions, prerequisites, or a decision rule for selecting this tool over nearby siblings.

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 genuinely useful behavioral guarantee: 'No identifiers are retained' — this addresses privacy and side effects. However, with no annotations and no output schema, it remains unclear whether this tool performs a remote call, mutates state, or depends on all/some of the input fields. The disclosure is partial, not comprehensive.

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 no filler. The primary action is front-loaded, and the privacy statement is the only additional sentence, earning its place as high-value behavioral context.

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?

Although parameter documentation is complete, the tool's core behavior is under-specified: it has four mutually-related optional inputs, no output schema, and no explanation of what classification result an agent should expect. The ambiguous relationship between the inputs and the classification output makes the description incomplete 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%, with each parameter (url, host, json, zone) individually documented. The tool description adds no parameter-level meaning, so the baseline 3 applies: the schema carries the heavy lifting and the description does not need to compensate.

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 uses a specific verb ('Show') and identifies the target resource ('this request'), but it never explains what the classification is or what dimensions are being classified. It is not a tautology, yet it is vague enough that an agent cannot predict what categories or labels the tool will return.

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 given about when to use this tool versus siblings like 'normalize-url', 'validate-json', or 'timezone'. There are no exclusions, prerequisites, or examples, so an agent must infer when this classification tool is the right choice.

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, and the description does not disclose any behavioral traits such as side effects, authorization requirements, rate limits, or what data is discarded. The description's claim that it splits hostnames contradicts the schema's inclusion of JSON validation, timezone, and URL parameters, making the tool's actual behavior opaque and potentially misleading.

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 short, but it is under-specified and lacking crucial structure. It does not even form a complete sentence, and it omits information about what the tool returns or how outputs are structured, making it inadequate rather than concise.

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 tool has 4 parameters, no annotations, no output schema, and no sibling context, the description is far too incomplete for an agent to select and invoke the tool correctly. A complete description would need to explain the relationship between hostname splitting and the diverse parameters, as well as the return format.

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 has 100% description coverage, the descriptions themselves are generic and disconnected from the tool's stated purpose. For example, 'JSON text to validate; discarded after the check' and 'IANA timezone name' do not logically follow from 'Split a hostname into labels'. The description adds no meaning that clarifies how these parameters should be used together.

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 'Split a hostname into labels without WHOIS or ownership data' is almost a tautology of the tool name 'domain-shape' and ambiguous about what the tool actually does. It also does not align with the input schema, which contains 4 parameters including 'json' and 'zone' that have no clear relation to splitting a hostname. An agent cannot reliably infer the tool's real function from this description.

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 alternatives, nor any mention of prerequisites or conditions. The description is too vague to inform an agent about appropriate invocation contexts. The sibling tool names were not provided, so no comparative context exists to differentiate usage.

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, and it carries none: no side effects, no return format, no call semantics. Worse, the schema exposes 'url', 'host', and 'json' parameters that suggest URL normalization and JSON validation behaviors the description never acknowledges, making the definition actively misleading about what the tool does.

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 text is short and free of filler, but this is under-specification rather than conciseness. A single fragment with no verb and no callable instruction earns no credit for effective 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 zero required parameters, no annotations, and no output schema, an agent needs at least a clear call pattern and return description. This definition provides none, leaving the agent unable to determine what to pass or what to expect back.

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%, which normally justifies a baseline of 3, but the description adds no meaning to any parameter and fails to connect the params to the stated purpose: only 'zone' plausibly matches 'IANA timezone names', while url/host/json appear to belong to sibling tools. The description does not compensate for this internal inconsistency.

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 'Common IANA timezone names for clock calls' mostly restates the tool name ('iana-zones' = IANA timezone names) and adds only a faint context hint ('for clock calls'). It contains no verb, so an agent cannot tell whether the tool lists, validates, or returns these names, and the input schema (url/host/json params) actively conflicts with the implied purpose.

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' weakly implies a relationship to clock-related siblings (timezone, utc-time), but there is no guidance on when to use this tool versus alternatives, no exclusions, and no mention of how it fits with citation, normalize-url, or validate-json. An agent cannot decide between this and its siblings from the text.

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 does state that the tool fetches a public robots.txt and returns only group counts, which reveals the core behavior and output shape. However, it omits details like whether the URL/host must be public, how malformed inputs are handled, or any side effects beyond the fetch.

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 nine-word sentence that is front-loaded with the action and immediately narrows the output with 'group counts only.' Every word earns its place; there is no filler or redundancy.

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 no annotations and no output schema, and its four optional parameters are described in ways that conflict with the stated purpose. The description defines neither the return structure of 'group counts' nor how parameters map to the request. An agent would likely 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?

Schema description coverage is 100%, so the baseline is 3, but the description adds no parameter guidance and the schema descriptions are actively misleading in this context: 'url' is described as 'HTTPS URL to normalize or cite,' 'json' as 'JSON text to validate,' and 'zone' as 'IANA timezone name.' This leaves the agent unable to determine which parameter identifies the target robots.txt. The description does not compensate for this 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 description is a specific and concise statement: 'Fetch a public robots.txt and return group counts only.' It identifies a clear verb, resource, and an output restriction, and it is topically distinct from siblings like validate-json or citation. However, it does not explicitly name or exclude sibling tools, and the input schema's unrelated parameter descriptions slightly muddy the intended scope.

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 about when to prefer this tool over alternatives, nor does it specify which of the four optional parameters should be provided to fetch a robots.txt file. An agent is left to infer usage solely from the tool name and one-sentence description, with no exclusions or context.

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 reveals only one trait: 'payload discarded', but does not state whether the operation is read-only, what it returns, or any side effects or prerequisites. This is far too thin for an unannotated tool.

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 extremely short, but this is under-specification rather than effective conciseness. It provides almost no usable content and does not earn its place as a functional 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?

This tool has 4 parameters, no output schema, and no annotations, yet the description gives no operational detail, return value, or invocation context. An agent cannot correctly select or call this tool based on the information provided.

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 tool description adds no meaning to the parameters—it never explains how url, host, json, or zone relate to a JWT header—but it does not contradict the schema either.

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 'JWT header shape, payload discarded' is a fragment that essentially restates the tool name and adds a cryptic note about payload handling. It lacks a verb or clear resource/action, so an agent cannot determine whether this tool validates, extracts, generates, or transforms a JWT header.

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 how it relates to siblings like validate-json, domain-shape, or normalize-url. No exclusions, alternatives, or contextual triggers 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?

The description discloses a genuine behavioral trait: query and fragment are dropped from the URL. With no annotations present, the description carries the burden, but it omits behavioral details for the other parameters, such as what happens with json or zone, and there is no mention of side effects, permissions, or return format.

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; the key behavior is front-loaded. However, it could have used an extra sentence or two to address the additional schema parameters, so it is concise but slightly 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 four parameters, no annotations, and no output schema, the tool description leaves significant gaps: three parameters (host, json, zone) are not addressed, and no output/return details are given. An agent would be unsure why those parameters exist or how they relate to the URL normalization purpose.

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 documents each parameter. The description adds a small behavioral note about query/fragment dropping, which relates to the url parameter, but it does not add meaning to host, json, or zone beyond their schema descriptions. 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?

States a specific verb ('Return') and resource ('a URL'), with precise scope: origin, host, and path, and explicitly says query and fragment are dropped. However, the description only covers the URL aspect while the schema also includes host, json, and zone parameters, creating ambiguity about the full purpose of the tool.

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 given on when to use this tool versus alternatives, and no exclusions are stated. The description implies it should be used for URL normalization, but it does not clarify what the host, json, or zone parameters are for or when they should be used.

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 full burden of behavioral disclosure. It only says the catalog is 'short' and 'common.' It does not state whether the operation is read-only, what it returns, whether the optional parameters are used or ignored, or any side effects.

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 or redundancy. It is concise and easy to scan, though the brevity sacrifices substantive guidance.

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 no annotations, no output schema, and four optional parameters that seem unrelated to a status-code catalog. An agent cannot determine what to pass, what the tool returns, or how the input schema connects to the stated purpose. This is a significant contextual 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?

Schema description coverage is 100%, so the baseline is 3. Each parameter has its own description, but the tool description adds no meaning about which parameters are relevant to the status-code catalog or how they affect the response. The schema remains the only source of 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 is a near restatement of the tool name: status-catalog is a 'short catalog of common HTTP status codes.' It lacks a clear verb and does not explain how the stated purpose relates to the input parameters (url, host, json, zone), making it ambiguous for an agent to understand what this tool does beyond its title.

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 instead of its siblings such as validate-json, normalize-url, or timezone. There are no conditions, alternatives, or exclusions mentioned; the intended use case is only weakly implied by 'HTTP status codes.'

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 implies a read-only operation ('Current time') but does not state the output format, behavior for invalid timezone names, or why the schema contains three unrelated 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?

A single sentence with no filler, and the core message is front-loaded. Every word contributes to the meaning, making it an exemplar of conciseness.

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 no annotations, no output schema, and a schema with three unrelated parameters and zero required fields. The description does not explain return format, error cases, or the role of the extra parameters, so it is 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. The description reinforces that 'zone' is the meaningful parameter but adds nothing about how to use url, host, or json, leaving their relevance 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 clearly identifies the tool's function: returning the current time for a named IANA timezone. It is specific enough to be distinguished from siblings like 'utc-time' and 'iana-zones', though it lacks an explicit verb such as 'get' or 'returns'.

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 given on when to use this tool instead of the siblings, nor which parameter (zone) should be supplied. The description also fails to warn that the unrelated url, host, and json parameters are not relevant to the tool's purpose.

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, but it only states that the timestamp is current. It does not disclose the output format (e.g., ISO 8601 vs epoch), precision, whether parameters affect the result, or any side-effect profile.

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 maximally concise with no wasted words. However, it borders on under-specification rather than deliberate economy, omitting essential behavioral details.

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 trivial time tool this could be sufficient, but the mismatched input schema and lack of output format details make the description incomplete. An agent cannot determine the return shape or whether the irrelevant-looking parameters matter.

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 coverage is 100%, the four parameters (url, host, json, zone) appear to belong to sibling tools and are unrelated to UTC time. The description fails to explain whether these parameters are accepted, ignored, or somehow alter the timestamp, creating confusion.

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?

"Current UTC timestamp" clearly states the tool returns the current UTC time. It lacks a verb and doesn't specify output format, but it is unambiguous and easily distinguishable from its unrelated siblings (citation, domain-shape, json-validate, etc.).

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 or how it relates to alternatives is provided. The description gives no context for selecting utc-time over any other approach to getting time.

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. It discloses a key behavioral trait: 'The body is discarded', clarifying the tool is non-persistent. It does not state the return format (e.g., boolean vs error), rate limits, or side effects, but for a validation check the disposal behavior is the most important behavioral disclosure.

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 purpose and immediately clarifying the destructive/disposal aspect. No wasted words; every phrase 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?

The input schema lists four unrelated-looking parameters (url, host, json, zone), and the description only explains 'json'. The tool's actual behavior for the other parameters and what counts as a valid result is unclear. Given a simple tool with no output schema, the description should clarify the expected return value or error behavior.

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. The description adds value by explaining the 'json' parameter's disposition ('discarded after the check') and the purpose of validation, but it does not clarify the relationship between 'url'/'host'/'zone' and the validation task, which is confusing.

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: 'Check whether a body is valid JSON', and adds that the body is discarded. It distinguishes the core validation purpose, though it doesn't explicitly differentiate from siblings; the sibling names suggest URL/timezone-related functionality, but the description itself doesn't name an alternative.

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 a quick validity check and explicitly notes the body is discarded, which warns against relying on it for storage. However, it provides no when-to-use versus alternatives, no preconditions, and no note about what makes JSON invalid.

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