HTTP 429 too-many-requests

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

With no annotations, the description carries the full burden. It adds one meaningful behavioral disclosure ('Page content is not stored'), which hints at a network fetch with a privacy guarantee, but it does not explain side effects, error behavior, or whether it is read-only beyond that. Some value is added, but significant gaps remain.

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 filler, and the core output is front-loaded in the first sentence. It could be slightly more instructive without bloating, but for what it says, it is concise and well ordered.

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 no annotations, no output schema, and four parameters that span unrelated concepts (URL, host, JSON, and timezone), the description is too thin. An agent would not know why 'host', 'json', and 'zone' are inputs, or how to combine them with the URL 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 all four parameters are already documented with meaningful descriptions. The tool description adds little parametric detail, but it does list the return fields (host, scheme, HTTP status), giving context that the schema does not.

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 ('Return') and a resource ('host, scheme, and HTTP status for a URL'), so an agent can tell this is a URL-inspection tool. It is distinguishable from the sibling list, though it doesn't explicitly differentiate itself.

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 alternatives like normalize-url or validate-json, nor about prerequisites or URL validity expectations. The agent must infer from the name and description alone.

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 exist, so the description carries the behavioral burden. It adds one genuinely useful trait ('No identifiers are retained'), disclosing a data-retention guarantee. However, it does not say whether the tool makes network calls, is read-only, or produces any side effects, leaving significant behavioral detail 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?

Two short sentences with no filler; the main action is front-loaded and the retention guarantee is a compact second sentence. The vague term 'classified' reduces information density slightly, but there is no wasted 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?

For a four-parameter tool with no annotations and no output schema, the description is thin. It does not clarify what the classification output looks like, which parameters are actually relevant, or what 'this request' refers to. An agent would likely need to invoke the tool experimentally to understand its 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?

All four parameters (url, host, json, zone) are fully documented in the schema with 100% coverage, so the baseline of 3 applies. The description adds no per-parameter semantics, such as which inputs are required, mutually exclusive, or intended for different classification scenarios.

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 verb and object ('Show how this request is classified'), but the classification dimension is never defined — it could refer to compatibility, format, or policy category. The name 'compatibility' hints at one dimension while the description says 'classified,' which is ambiguous, and there is no differentiation from sibling tools like citation or domain-shape.

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 appears. The description never states what inputs or scenarios should trigger this tool versus its siblings, nor whether it should be tried first. An agent is left to infer its role from the name alone.

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 behavior disclosure. It does reveal one useful trait: the tool will not perform WHOIS or ownership lookups, implying a local, read-only operation. However, it does not explain how inputs like url, json, or zone are processed, what 'labels' means in terms of output, or how invalid inputs are handled.

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 gets to the point immediately: 'Split a hostname into labels'. There is zero wordiness and the differentiator comes right after the verb. It is appropriately terse for a simple operation, though the under-specification of parameters limits its helpfulness.

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 four parameters, no annotations, and no output schema, the description is not complete enough for reliable use. It fails to explain how the url, json, and zone parameters relate to the stated purpose of splitting a hostname, or what the returned labels look like. An agent would struggle to determine which parameter to supply and what output to expect.

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 even though the description adds no parameter-level detail. The description's term 'hostname' maps loosely to the 'host' parameter but ignores url, json, and zone entirely, creating potential confusion about which parameter is actually the input to split. Still, the individual schema descriptions already document each parameter, so the description does not need to repeat them; it just misses the chance to clarify input selection.

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: 'Split a hostname into labels', which clearly identifies the core operation. The clause 'without WHOIS or ownership data' also differentiates it from ownership-lookup tools, giving it a distinct identity. However, the description does not reconcile this purpose with the four schema parameters (url, host, json, zone), leaving some ambiguity about what exactly gets split.

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 'without WHOIS or ownership data' implies this tool is for syntactic parsing only and should not be used when ownership information is needed — an implicit when-not-to-use hint. But it does not name alternatives, specify positive selection criteria, or explain how to choose among the four parameters. Guidance is present but only implied, not explicit.

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

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

No annotations are present, so the description carries the full burden of explaining behavior. It only says 'Meaning of HTTP 429' and discloses nothing about whether this is a lookup, what output it produces, whether it performs network requests, or any other behavioral traits.

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 short, but it is under-specified rather than usefully concise. It restates the tool name and provides no structured or front-loaded information beyond that, so the brevity does not serve the agent's decision-making.

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, no output schema, and overlapping siblings, the description is far too minimal. An agent cannot determine required inputs, output format, or how this tool differs from status-catalog, making it effectively non-actionable.

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 describes all four parameters individually, so the baseline is 3. However, the description adds no connection between these parameters and the tool's purpose; url, host, json, and zone seem unrelated to explaining HTTP 429, leaving the agent without guidance on which parameters 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?

The description is essentially a restatement of the tool name: 'http-429' and 'Meaning of HTTP 429' carry nearly the same information. It lacks a specific verb such as 'returns', 'explains', or 'looks up', and it does not distinguish this tool from the sibling 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 like status-catalog or other siblings. No context, prerequisites, or example scenarios are provided, so an agent cannot infer the appropriate selection conditions.

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 fails to disclose what happens when the tool is invoked, what it returns, whether it performs a check or lookup, or any side effects. The phrase 'Common IANA timezone names' only describes content, not 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 very short and free of filler, but it is under-specified rather than concise. A seven-word noun phrase provides no operational structure or actionable content for an agent.

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 four optional parameters, this description is far from complete. It does not state what the tool returns, when to call it, or which parameter or combination of parameters should be used, leaving the agent to guess.

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 even without additional parameter guidance. The description adds no parameter-level meaning and does not explain why url, host, and json coexist with zone, but the schema itself already documents each parameter clearly.

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 noun phrase that mostly restates the tool name: 'Common IANA timezone names for clock calls.' It names no operation, so it is unclear whether the tool lists, resolves, validates, or returns timezone names. It also does not differentiate it from sibling tools like timezone and utc-time.

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 its siblings. The only context hint is 'for clock calls,' which is too vague to distinguish it from timezone or utc-time, and no exclusions or alternative tool names are mentioned.

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 mentions that only group counts are returned (useful) but does not disclose whether the fetch respects timeouts, handles errors, follows redirects, or caches results. For a network-fetching tool, the lack of these behavioral details 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, brief sentence that is easy to parse and front-loads the core action and result. It earns a 4 for efficiency, though it could reasonably add one more sentence about usage or behavior without becoming verbose.

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 required parameters, no output schema, and no annotations, the description does not provide enough context for an agent to confidently invoke it. It does not explain the role of parameters like 'json' or 'zone' in relation to robots.txt, nor the exact structure of 'group counts'. This incompleteness could lead to misuse.

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 a clear hint about the primary parameter (url for fetching) and the output scope, but it does not clarify which parameters are actually used for the robots.txt fetch versus irrelevant ones (e.g., zone appears unrelated). This leaves room for guesswork.

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 ('Fetch') and resource ('robots.txt') and notes the output is 'group counts only', which gives a clear sense of the operation. However, it does not distinguish this tool from siblings like 'citation' (which may also fetch URLs), leaving some ambiguity about when this tool is the right one.

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 a usage context ('public robots.txt') but offers no guidance on when to choose this over alternatives, nor any exclusions (e.g., when not to use it). An agent cannot infer when this tool should be preferred over sibling tools or when it would be inappropriate.

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 does usefully state that query and fragment are dropped, which is a real behavioral trait. However, it does not disclose behavior for invalid URLs, non-HTTPS inputs, or what happens when the other schema parameters (host, json, zone) are supplied.

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, zero filler, and the most important behavioral constraint ('Query and fragment are dropped') is front-loaded. Every word 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?

Given four parameters, no required fields, and no output schema, this short description is not complete enough. It explains the URL path but leaves the host, json, and zone parameters unexplained, and it does not describe the return structure beyond naming three components. An agent would be uncertain how to invoke the tool for most of its declared inputs.

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 each parameter has a baseline description. The tool description adds semantics only for the url parameter (defining the output and dropped components) but says nothing about host, json, or zone, which appear unrelated to the stated behavior. The baseline 3 applies, but the description does not help reconcile the confusing parameter set.

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 action ('Return') and concrete outputs (origin, host, path) for a URL, with a clear note that query and fragment are dropped. It is clear for the main URL-normalization use case, though it does not explicitly distinguish itself from sibling tools or mention the other parameters in the schema.

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 when to use the tool (when you need origin, host, and path without query or fragment) but provides no explicit guidance about alternatives, exclusions, or conditions. With four unrelated-looking parameters and a sibling list, the agent is left to infer appropriate 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?

No annotations are provided, so the description carries the full burden. It discloses only that the tool is a 'short catalog' and gives no behavioral details: no side effects, no data handling, no return format. It does not even confirm whether the tool performs any action beyond displaying static codes. There is no contradiction with annotations because none exist.

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 and front-loaded, which is efficient, but it is under-specified rather than concise. One sentence with minimal content earns a middle score; it is not verbose, but it omits necessary 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?

Given no output schema and no annotations, the description is the sole guide, yet it provides almost no actionable information. The four parameters are not explained in relation to the tool's purpose, there is no hint of how status codes are used, and the agent is left with a catalog name and a vague phrase. This is highly inadequate even for a simple reference 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%, meaning each parameter has a description in the schema. However, the tool description itself adds no meaning to the parameters. The parameters (url, host, json, zone) seem unrelated to HTTP status codes, and the description does not explain how they relate to the catalog. A baseline of 3 applies since the schema carries the parameter details, but the mismatch between parameters and described purpose lowers the value further.

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 it is a 'catalog of common HTTP status codes', which is vague and does not convey a specific action or resource. It resembles a reference resource rather than a tool with a clear verb+resource objective. The title 'status-catalog' is essentially restated, and it does not differentiate from sibling tools.

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. Sibling tools like 'citation', 'compatibility', 'normalize-url', and 'validate-json' suggest different functions, but the description never mentions them or conditions for selection. The tool could be a status-code lookup, but its usage context is entirely unstated.

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 it does communicate the core behavior: a read-only current-time lookup. However, it does not disclose edge-case behavior such as missing or invalid timezone names, possible network dependence, or the output format, which leaves some transparency 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 a single, tightly worded sentence with no filler. It front-loads the core function and contains only information necessary to understand the tool's purpose.

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 minimally adequate for a simple lookup: an agent can infer that it should provide an IANA zone via the zone parameter. But it is incomplete in important ways: no annotations, no output schema, no mention of error behavior, and no clarification of the irrelevant schema fields or the fact that zone should logically be required.

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 zone parameter is clearly described as 'IANA timezone name,' aligning with the description. The description adds little beyond that, but the schema also includes unrelated optional fields (url, host, json) and no required parameters, and the description does not clarify that zone is the intended meaningful input.

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, specific function: returning the current time for a named IANA timezone. It is not a tautology and is distinguishable from sibling tools like utc-time (UTC) and iana-zones (listing zones), though it does not explicitly name those alternatives.

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 utc-time, iana-zones, or other siblings. There are no conditions, exclusions, prerequisites, or alternative routing, so the only usage signal is the implied meaning of the 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 behavioral burden. It clearly implies a side-effect-free read operation, but it does not disclose whether any of the four declared parameters affect or are ignored by the call, nor the timestamp format or precision.

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?

One short, front-loaded phrase with no filler words. It is easy to parse and appropriately sized for a simple time retrieval tool, though the brevity sacrifices necessary detail covered in other dimensions.

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 no output schema, no annotations, and a mismatched input schema, the description is incomplete. It does not specify the timestamp return format, confirm that all parameters are ignored, or help the agent choose between utc-time and the closely related timezone 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?

The input schema has high description coverage, but the parameter descriptions (URL normalization, JSON validation, hostname, IANA timezone) are unrelated to a UTC timestamp tool. The description adds no clarification that zero parameters should be used, leaving the schema misleading rather than helpful.

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 states the tool's output: the current UTC timestamp. It is not a tautology and is reasonably distinguishable from siblings like timezone and iana-zones, though it does not explicitly contrast itself with them.

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 utc-time versus the sibling tools timezone or iana-zones. An agent must rely on the tool name and description alone to infer that this is specifically for UTC timestamps.

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?

Since no annotations are provided, the description carries the full burden of behavioral disclosure. The sentence 'The body is discarded' is a useful side-effect disclosure about data handling. However, it does not mention potential side effects like network requests, state changes, or what happens on invalid JSON, so the 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?

Two short sentences with the core purpose front-loaded and the side-effect statement earning its place. There is zero filler, and the structure makes the key fact immediately visible.

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 and no output schema, the description is underspecified. It does not clarify how url, host, and zone relate to the validation, nor what the tool returns for valid vs invalid JSON. An agent would have to guess about the tool's other parameters and return 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?

The input schema has 100% description coverage, so the baseline is 3. The description adds no parameter-specific meaning beyond the schema; the term 'body' loosely maps to the 'json' parameter, but it does not explain the roles of url, host, and zone. The schema already does the heavy lifting for parameter semantics.

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 states the operation: 'Check whether a body is valid JSON.' The verb + resource combination is specific and distinct from the sibling tools, which all relate to URLs, time, or citation rather than JSON validation. There is minor ambiguity in the word 'body' not being tied to the 'json' parameter, but the intent is unambiguous.

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 instead of the sibling tools. It states what the tool does but provides no context, prerequisites, or exclusions that would help an agent decide between validate-json and alternatives.

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