Server Quality Checklist

Tool Scores

• create_chartA
  3.5/5.0
  Behavior3/5

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

  With no annotations, the description carries the transparency burden. It discloses key behavior: returns a permanent, hosted URL that renders server-side and works without a client-side library. However, it omits operational details like authentication (icac), network effects, rate limits, or the fact that format=png fetches the image, which are important for a creation tool.

  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 two concise sentences that front-load the action and result. It includes valuable context (permanent URL, server-side rendering, no client-side library) without waste. Every word adds meaning.

  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 the tool's complexity (12 parameters, nested objects, no output schema, no annotations), the description gives a high-level purpose but does not mention the required 'type' parameter, the optional output format (url/png/both), or how to handle authentication. The rich schema compensates, but the description alone is not fully complete for correct invocation.

  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?

  Schema description coverage is 100%, so the baseline is 3. The description itself adds no parameter-level meaning, but the schema fully documents each parameter, including nested objects and constraints, so the agent can rely on the schema.

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

  Purpose4/5

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

  The description clearly states the tool creates a hosted chart URL from a semantic chart description, listing supported chart types. It names the specific resource and outcome (Image-Charts URL), but does not explicitly differentiate itself from siblings like image_charts_url.

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

  Usage Guidelines3/5

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

  The description implies use for server-side rendering and embedding without a client-side library, providing some context. However, it does not explicitly state when to use this tool over alternatives like image_charts_url or list_chart_types, nor does it mention exclusions.

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

• image_charts_urlA
  4.1/5.0
  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 adds meaningful context by stating that the URL is signed automatically when icac is provided and IMAGE_CHARTS_SECRET is set. It also implies a pass-through behavior ('raw parameters') without validation, which is useful. However, it does not disclose return format variations (e.g., what happens when format='png') or any error behavior, leaving some gaps.

  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 two sentences with no wasted words. It front-loads the key concept ('Escape hatch for full control'), then provides the mechanism and an important behavioral note. Every sentence earns its place.

  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?

  The tool has 35 parameters, no output schema, and no annotations, so the description needs to cover more ground. It clearly explains the core behavior and signing, but it does not clarify how the 'format' parameter affects the output (url vs png vs both). This is a notable omission given that the schema includes a format param with enum values, and without an output schema the agent cannot infer the return structure. Thus, the description is adequate but not complete.

  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 lists several example parameters (cht, chd, chs, chco, chxt, chxl, chm) but does not add new semantics beyond what the schema already provides. The mention of signing with icac is also present in the schema's parameter description, so the description adds no extra value for parameter understanding.

  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 a specific verb and resource: 'pass raw Image-Charts parameters ... and get the hosted image URL.' It also distinguishes itself from siblings by calling it an 'escape hatch for full control' and mentioning the signing behavior, which differentiates it from a high-level chart creation tool like create_chart.

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

  Usage Guidelines4/5

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

  The phrase 'escape hatch for full control' implies this tool is for users who need to bypass higher-level abstractions and specify raw parameters directly. This provides clear context, but it does not explicitly mention when to prefer this over create_chart or list_chart_types, nor does it state when not to use it. The guidance is implied rather than explicit.

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

• list_chart_typesA
  4.5/5.0
  Behavior4/5

  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 what the tool returns (semantic types, mappings, descriptions, inputs, limitations) and implies a safe read-only operation. Missing details like response format or pagination prevent a higher score.

  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?

  A single, information-dense sentence front-loaded with 'Discovery:' covers purpose, content, and limitations efficiently. Every clause adds value without redundancy.

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

  Completeness5/5

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

  The tool has no parameters and no output schema, but the description thoroughly explains what it returns and its scope relative to siblings. It fully covers the discovery use case, including what Image-Charts cannot render.

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

  Parameters4/5

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

  With zero parameters and 100% schema description coverage, the baseline is 4. The description's mention of returned content (mappings, inputs) provides context beyond the empty schema, though no parameter-level detail is needed.

  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 returns every semantic type accepted by create_chart, including mappings, descriptions, inputs, and unrenderable concepts. This specific verb+resource combination distinguishes it from sibling tools like create_chart and image_charts_url.

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

  Usage Guidelines4/5

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

  The prefix 'Discovery:' signals the intended use case as a discovery/list tool, contrasting with the action-oriented siblings. However, it does not explicitly state when not to use it or name alternatives, so it falls short of full explicit guidance.

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