PixilUI components

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

Annotations already establish readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful context beyond that: the return value is a command string plus a config snippet, and Pro items require an environment variable before use.

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 tightly written sentences with no filler; what the tool returns comes first and the prerequisite follows. Every clause carries distinct information.

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 simple one-parameter read tool with no output schema, the description covers both the primary return (a CLI command) and the secondary return (the registries snippet) plus the token prerequisite. Nothing an agent needs to call it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% and the single slugs parameter is documented with an example in the schema, so the baseline is 3. The phrase 'every listed item' loosely maps to slugs but adds no batching, ordering, or error semantics beyond the schema's 1-30 item bounds.

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 concrete output: a single shadcn CLI command that installs every listed item, plus a components.json registries snippet. That is a specific verb-plus-resource, and it is clearly different from get_item or get_source, though it never names a sibling to route away from.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is only implied by the wording 'installs every listed item into the project'; there is no explicit statement of when to pick this over get_item or get_source and no exclusions. It does surface one real prerequisite, that Pro items need PIXILUI_TOKEN, which keeps it above a bare minimum.

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

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

Annotations already establish readOnlyHint=true and openWorldHint=false, so safety is covered; the description instead adds genuinely useful entitlement behavior — free items always include source, Pro items only with a valid Pro token. It does not state what happens on a missing slug or an invalid/absent Pro token (error vs. silent omission), which is the main remaining 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?

It is one compact sentence and front-loaded, but 'when to use it and when not' is wasted space that also misleads the reader into expecting selection guidance. The rest is a dense but efficient inventory of returned content.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description carries the burden of describing the return payload and does so thoroughly by enumerating each section. For a read tool whose annotations already cover safety, the only notable omission is failure behavior for bad slugs or insufficient entitlement.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so baseline is 3, but the description adds real meaning about the includeSource lever: source is gated by the item's tier and a valid Pro token, so the parameter is a request rather than a guarantee. That is semantic value the schema ('Include the source files when allowed') only hints at.

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 conveys a specific resource (one item/component) and enumerates exactly what the response bundles: props table, keyboard, accessibility, motion, files, npm dependencies, install command, and source. It stops short of a crisp verb-led statement and never contrasts with siblings like get_source or get_install_command, whose content this tool appears to include, so the agent must infer the overlap.

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 'when to use it and when not' reads as a description of a field inside the returned docs, not as guidance about when to call this tool versus get_source, get_install_command, or get_skill. No conditions, prerequisites, or alternatives are given for tool selection.

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

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. Beyond that, the description discloses the important default behavior (no argument returns SKILL.md and the file list, which doubles as the index), though it says nothing about what happens with an invalid file name.

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 front-loaded sentence with the default behavior stated before the alternative. The parenthetical file enumeration is long but each item is informative about available content, so it earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a one-parameter read-only getter with no output schema, the description covers what is returned in both modes and lists the available files without needing an output schema. Only edge-case handling (unknown file names) is missing.

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% for the single optional 'file' parameter. The description still adds real meaning the schema lacks: what omitting the parameter returns versus what passing a file name returns, which is the key selection decision for the agent.

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 resource (the PixilUI agent skill) and enumerates its contents (SKILL.md plus rule files for design, motion, copy, accessibility, etc.), so an agent knows exactly what this tool fetches. Differentiation from siblings like get_item or get_source is only implied by the resource name rather than stated.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The two invocation modes are spelled out: call with no file to get SKILL.md plus the file index, or with a file name to get a single file. That is clear usage context, though it does not name when to prefer a sibling tool instead.

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

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

Annotations already cover read-only/non-open-world safety, and the description adds genuinely new operational context: Pro items require a valid Pro token, and the standalone shape yields a self-contained .tsx depending only on react and motion. It stops short of describing error behavior or what happens when a Pro item is requested without a token.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences, purpose front-loaded, alternative routing second, parameter behavior last. Dense but readable; the parenthetical "(free components)" and the trailing shape clause are slightly compressed rather than cleanly 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?

No output schema exists, so the description carries the return-format burden and does so for both shapes (files with install paths vs. one inlined .tsx). Only the Pro-token failure mode and the exact file payload contents remain unstated.

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?

With 100% schema coverage the baseline is 3, but the description adds meaning beyond the schema text: standalone is scoped to free components and explicitly requires no Tailwind and no other items, which constrains expectations more than the schema's "styles and helpers inlined" wording.

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 first sentence states a specific verb and resource (raw files of one item, with install paths) plus the audience constraint that defines the tool (projects that cannot run the shadcn CLI). It is clearly distinguishable from get_install_command and get_item.

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?

"Prefer get_install_command" explicitly routes the agent to the alternative and the preceding clause gives the condition that selects this tool instead. The one gap is that it does not say what to do if a Pro token is unavailable (error vs. partial result).

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

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered and the description's added value is mainly the disclosed return shape (slug, title, kind, category, tier, one-line description). It says nothing about result volume, ordering, or whether "every" truly means unpaginated, which is the remaining behavioral 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?

Two sentences, zero filler, with purpose and return shape front-loaded. Nothing is repeated from the schema or annotations.

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 simple read-only tool with two optional parameters and no output schema, listing the returned fields is exactly the right compensation. The only omission is whether results are ordered or paginated, which mildly matters when browsing the full 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% and the enum for tier is fully specified, so the schema carries most of the weight; baseline 3 applies. The description only restates that category and tier act as optional filters, adding no format or semantics beyond the schema's own examples.

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?

"Browse every PixilUI item" gives a specific verb and resource, and the enumeration of returned fields (slug, title, kind, category, tier, description) makes the output concrete. It stops short of naming siblings like search_items or get_item, so an agent must infer that this is the unfiltered/enumerating counterpart rather than a lookup or text search.

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?

"Optionally filtered by category or tier" implies when the filters apply, and the word "every" hints at full enumeration rather than targeted retrieval. However, there is no explicit statement of when to prefer this over search_items or get_item, nor any mention of prerequisites or result-size expectations.

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 readOnlyHint/openWorldHint annotations already cover the safety profile, so the description's job is to add search-specific behavior. It does disclose the indexed fields and result ordering ("returns the best matches first"), which is genuinely useful, but says nothing about match scoring, empty-result behavior, or how filtering interacts with ranking.

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 short sentences ordered as purpose, query style, then call-to-action. The example queries are the highest-value content and are front-loaded, and nothing is redundant with the schema or annotations.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description at least signals ranking order and the fact that matches are returned, which is the main thing an agent needs to know before calling. It could say more about result shape or what an empty match implies, but for a 5-param search tool this is close to complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so baseline is 3, but the description goes beyond the schema's "What the UI has to do" by supplying three concrete natural-language query examples that teach the intended phrasing style. The other four params (tier, type, category, limit) are left to the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

"Find PixilUI items for a UI job" pairs a specific verb with a specific resource, and "Searches titles, descriptions, when-to-use notes and tags" defines the search surface precisely. It never names a sibling (get_item, list_items) to draw the boundary explicitly, so search-vs-browse-vs-fetch has to be inferred from vocabulary rather than stated.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

"Call this before writing any UI by hand" gives an unambiguous trigger for reaching for this tool, and the three quoted example queries show how to phrase a request. There is no when-not guidance and no explicit routing to get_item or list_items once a match is known, which keeps it below a 5.

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