可视化用法与 spec 说明（怎么把数据变成页面）

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows this is a safe, side-effect-free operation. The description adds context about the content of the guide (e.g., the note about writing limits as 'this doesn't explain much' rather than a conclusion), but it doesn't disclose any behavioral traits beyond what annotations cover. The bar is lower because annotations are rich; the description adds some value but not substantial behavioral detail.

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 dense but well-structured: it opens with the purpose, then lists topics and gives practical guidance, and ends with parameter and example. Every sentence adds value, and it's appropriately concise for a guide tool. Slightly dense formatting but still readable.

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 guide tool with one optional parameter and an output schema (present), the description covers all necessary information: purpose, topic enumeration, usage recommendations, and parameter details. It also includes specific formatting conventions (µs units) and warns about limits phrasing. 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?

The schema has one optional parameter 'topic' with no description and 0% coverage, but the description fully compensates by enumerating all valid values (howto, views, spec, limits, all) with their meanings and defaults. It also notes the parameter is optional and provides a call example, giving the agent complete information to select the right topic.

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 is a manual for view_render, covering how to turn collected data into pages, the five view types, and how to write custom specs. It explicitly names the resource (view_render) and the three main functions, distinguishing it from sibling tools like mdk_guide (a general MDK guide) and view_render 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?

The description provides topic-based usage guidance: it recommends starting with howto for most cases, and lists when to use views, spec, limits, and all. It also advises that most scenarios don't require reading spec, and gives a concrete tip about spec units. It doesn't explicitly compare with alternatives, but the tool's purpose as a guide for view_render makes the usage context clear.

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