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

Annotations already establish readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description still adds real context beyond that: the return is Markdown, and supplying a topic narrows the response to a single section rather than the full guide. It doesn't mention guide length or cost of fetching the whole thing, which would help an agent decide between modes.

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 default behavior and return format are front-loaded before the topic enumeration, and every topic gloss carries distinct information. The second sentence is long and comma-heavy, but no clause is filler.

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?

There is no output schema, so the description must describe return values, and it does — Markdown guide or a single section. With one optional parameter, complete topic enumeration, and annotations covering safety, an agent has everything needed to invoke it correctly.

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 0% and the description fully compensates: every enum value is defined with specific content ("export" = render_snapshot and export_diagram parts, watermark, download links, errors). An agent can pick a topic without guessing what it contains.

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?

Opens with a specific verb and resource ("Returns the Archboard guide for agents as Markdown") and enumerates exactly what the guide covers: workflow, document format, layout rules, plan limits and errors. This is unmistakably the documentation tool among diagram-manipulation siblings like create_diagram and export_diagram.

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?

It clearly distinguishes the two calling modes: omit topic for the whole guide, pass a topic for "one detailed section instead." Each topic label is paired with the concrete concern it resolves (e.g. "images" for limits, errors, upload links), which routes the agent well. It stops short of saying when to read the guide relative to the sibling workflow tools.

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