Server Quality Checklist

Tool Scores

• 21st_magic_component_inspirationC
  2.9/5.0
  Behavior3/5

  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 states the tool returns JSON data without generating new code and only returns text snippets, which clarifies its read-only nature and output format. However, it doesn't address potential limitations like rate limits, authentication needs, or error handling, leaving gaps in behavioral understanding for a tool with no annotation coverage.

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

  Conciseness4/5

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

  The description is relatively concise with three sentences that convey key information: when to use the tool, what it returns, and a post-call action. However, the first sentence is somewhat redundant ('see component, get inspiration, or /21st fetch data'), and the structure could be more front-loaded by immediately stating the core purpose. Overall, it's efficient but not perfectly streamlined.

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

  Completeness3/5

  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 2 parameters with full schema coverage, the description provides basic context: it specifies the tool's purpose, output format (JSON data/text snippets), and a required post-call action. However, it lacks details on error cases, response structure, or integration examples, making it incomplete for a tool that fetches external data without structured output documentation.

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

  Parameters3/5

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

  The input schema has 100% description coverage, providing clear details for both parameters ('message' and 'searchQuery'). The description adds no additional parameter semantics beyond what the schema already documents, such as explaining how these parameters interact or their impact on results. This meets the baseline score of 3, as the schema adequately covers parameter information.

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

  Purpose3/5

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

  The description states the tool fetches data and previews from 21st.dev and returns JSON data of matching components, which clarifies its purpose. However, it doesn't clearly differentiate from sibling tools like '21st_magic_component_builder' or 'logo_search', leaving ambiguity about when to use each. The phrase 'see component, get inspiration, or /21st fetch data' is somewhat vague rather than specific.

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

  Usage Guidelines2/5

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

  The description provides minimal guidance: 'Use this tool when the user wants to see component, get inspiration, or /21st fetch data and previews from 21st.dev.' It doesn't specify when to use this tool versus alternatives like '21st_magic_component_builder' or 'logo_search', nor does it mention any exclusions or prerequisites. This lack of comparative context limits its effectiveness in guiding tool selection.

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

• 21st_magic_component_builderA
  4.1/5.0
  Behavior3/5

  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 explains that the tool returns text snippets and requires manual integration afterward, which is useful context. However, it doesn't disclose important behavioral traits like whether this is a read-only operation, if it makes external API calls, potential rate limits, or error handling for invalid requests.

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

  Conciseness5/5

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

  The description is extremely concise and well-structured with only three sentences, each serving a distinct purpose: trigger conditions, tool limitation, and required follow-up actions. There's zero wasted text, and the most important information (when to use the tool) is front-loaded.

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

  Completeness3/5

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

  Given no annotations and no output schema, the description provides adequate context for a simple tool but has gaps. It explains the tool's purpose and usage well but doesn't describe what the output looks like (format, structure, or content of returned snippets) or address potential limitations or error conditions that would help an agent use it correctly.

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

  Parameters3/5

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

  With 100% schema description coverage, the baseline is 3. The description doesn't add any parameter-specific information beyond what's already in the schema (message and searchQuery parameters are fully documented in the schema). No additional syntax, format, or usage details for parameters are provided in the description.

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

  Purpose5/5

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

  The description clearly states the tool's purpose: 'returns the text snippet for that UI component' when users request new UI components. It specifies the exact trigger conditions (mentions of /ui, /21, /21st, or specific component types) and distinguishes it from sibling tools by focusing on returning component snippets rather than inspiration or logo searches.

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

  Usage Guidelines5/5

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

  The description provides explicit usage guidelines: 'Use this tool when the user requests a new UI component' with specific trigger examples, and distinguishes it from alternatives by stating 'This tool ONLY returns the text snippet' and requiring follow-up actions. It clearly defines when to use this tool versus other approaches.

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

• logo_searchA
  4.3/5.0
  Behavior4/5

  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 effectively describes key behaviors: it returns logos in specified formats, supports single/multiple searches with category filtering, and can provide themes if available. However, it lacks details on error handling, rate limits, or authentication needs, leaving some behavioral aspects unclear.

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

  Conciseness4/5

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

  The description is well-structured with clear sections (purpose, usage guidelines, examples, format options, result details) and uses bullet points for readability. It is appropriately sized but includes some redundancy (e.g., repeating format options in the first sentence and a dedicated section), which slightly reduces efficiency.

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

  Completeness4/5

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

  Given the tool's complexity (2 parameters, no output schema, no annotations), the description is mostly complete: it covers purpose, usage, examples, formats, and result details. However, it lacks information on error cases, pagination, or response structure, which could be important for a search tool. The absence of an output schema means the description should ideally explain return values more thoroughly.

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

  Parameters3/5

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

  The schema description coverage is 100%, so the baseline is 3. The description adds minimal value beyond the schema by mentioning 'category filtering' (implied in queries) and 'themes if available' (not in schema), but it does not provide additional syntax or format details for parameters. It compensates slightly by explaining format options and result components, but parameter-specific semantics are limited.

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

  Purpose5/5

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

  The description clearly states the tool's purpose with specific verbs ('Search and return logos') and resources ('logos in specified format'), distinguishing it from sibling tools like component builders by focusing on logo retrieval rather than creation or inspiration. It explicitly mentions the supported formats (JSX, TSX, SVG) and capabilities like category filtering and theme options.

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

  Usage Guidelines5/5

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

  The description provides explicit guidance on when to use this tool, including specific triggers like '/logo' commands and requests to add company logos not in the local project. It also offers example queries (e.g., single/multiple companies, command style) that clarify appropriate contexts, though it does not explicitly state when NOT to use it or mention alternatives.

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